Rabbit Yarn

THE angora rabbits owned by Mrs. Paul Venne of Penacook, New Hampshire work for their keep. They provide soft fur which she plucks instead of shears to prevent it from matting. This she spins into yarn and knits into such serviceable items as bonnets, berets, gloves and sweaters. And the bunnies don’t seem to mind a bit.

Deer Hunts Elephants

LITTLE-game hunter on a big scale is I Jack Deer, 55-year-old New York businessman. He has a collection of over 1,400 miniature elephants, all with upturned trunks. They are made of ivory, china and glass gathered from all countries of the world. His most prized is one owned by the late Flo Ziegfeld, also a collector.

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The Amateur Telescope Maker’s Page

AT a cash outlay of $300, boys at a Hawaiian school built a 20-inch reflecting telescope which has been valued at $20,000. It is said to be one of the largest telescopes in the Pacific area. With the exception of the grinding of the mirror, all the work was done by the students of the Kamehameha school, a private grammar school named after Hawaii’s greatest king. The f-6 mirror was donated by a government employee who ground it himself, taking six months for the job.

The scope is of all-steel construction and weighs 3,000 pounds. The mirror alone weighs 125 pounds. The mounting is German-type equatorial. At present it is manually operated but the ambitious young astronomers are planning to add a clock mechanism.

A good deal of the material used in the construction consists of spare parts and pieces found lying around the Kamehameha machine shop, according to Ardean Sveum, shop instructor, who directed work on the project. An observatory site has been selected and plans are proceeding for the early construction of a permanent building near the school.

Telescope Mirror Grinding Tool

Many an amateur astronomer has found himself in the position of owning a glass or pyrex disk suitable for fashioning into a telescope mirror but without a suitable tool. A tool, of course, can be purchased from one of the numerous telescope supply houses. However, if the mirror is a large one, this is expensive, or if the disk is not of a standard diameter, it might not be possible to find a suitable tool. By following the procedure outlined, a tool can be made for any size disk, inexpensively, and with very little effort.

You’ll need a number of the small hexagonal tiles used for bathroom floors and a matrix. The matrix can be cement or any plaster-type material that sets hard. The tool illustrated was made of dental stone, a powder used in dental work to make casts for bridges or plates. This material is readily available at any dental supply house, is inexpensive, and sets extremely hard. This tool is 8-in. in diameter and 1-1/2 in. thick. It required three pounds of dental stone and 42 tiles.

The first step is to fashion a stiff collar around the circumference of the disk. Cut strips of paper, newspaper will do, somewhat longer than the circumference of the disk and 1/4 in. wider than the thickness of the disk plus the thickness of the desired tool. Place these strips around the disk and secure the end with masking tape, Scotch tape or string.

Place as many of the bathroom tiles on the surface of the disk and within the surrounding paper collar as will fit. Edges of the outer tiles should touch the collar. Place the tiles close together so that points of tiles touch tile edges, but try to minimize the number of edges touching edges as this decreases the tile area secured by the matrix.

Mix the matrix material with cold water until it is about the consistency of thick cream. Be sure it is mixed thoroughly so that no lumps of dry powder are left to weaken the tool. Carefully spoon the mixture onto the tiles so as to avoid disarranging the pattern. Then, when the tiles are covered, pour out the rest of the mixture to within 1/4 inch of the top of the collar.

Allow ample time for setting; at least one-half hour if using dental stone. Slide the cast from the mirror (used as a guide) and strip off the paper collar.

Allow the tool to set overnight, then smooth off the rough or raised edges of matrix material, using a fine file. Be careful not to file tile edges lest they be damaged. After the first few minutes of using the tool to rough grind the mirror, the surface of the tool will have smoothed off even with the inset tiles. • —R. W. Ferguson

ELECTRIC PENCIL SHARPENER

Get a point on your pencils the easy way—-by motorizing your sharpener.

WHY not add an electric motor to your hand driven pencil sharpener in your home or office and make the chore of putting a point on your pencils a real pleasure? The arrangement outlined in this article does not call for mutilating or altering your present sharpener; merely remove the handle and proceed to mount the unit in the manner shown below. In converting your sharpener, choosing the correct motor is very important. Your motor should be quite powerful, of at least one-sixteenth horse power and oper- ate in the neighborhood of 1150 r.p.m.

For transmitting the power a worm gear unit, having a ratio of approximately twelve to one, is used. These gears can be purchased from any gear company at the cost of only a fraction of a dollar. Mount the 1 in. diameter worm wheel to the sharpener shaft by first turning an adapter, one end of which is pressed into the wheel and the other screwed directly on the sharpener shaft. A cotter pin through the worm wheel hub and a set screw through tapped end of the adapter will insure the gear from slipping when the sharpener is in operation.

Next obtain a wooden base of the general dimensions shown and mount the sharpener in place. Block motor so worm meshes with wheel.

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SCAMPER

Using an air propeller, this model zips along at 40 mph as a car and does 20 as a ski-equipped boat.

By Paul Del Gatto

BUILT as a car, this model is a supercharged bundle of energy. Free-running, it surges forward as if shot from a cannon and tops 40 mph. Most people won’t have the space to let it go and will have to use a tether. Even at that, it will do better than 35.

Personally, our favorite version is the one featuring the hydro-ski arrangement. Though not as fast as the car, 20 mph is still very high for a boat of this size. Yet it isn’t the speed that impresses us so much as the sight of this unusual water bug rising up on the skis. The air prop lends to the fascination by creating the illusion of some weird form of aircraft skimming across the water. Of course you may experience a somewhat different type of reaction, but one thing is certain: no matter which version you try, you will enjoy it every bit as much as we did.

The chief material used in the construction of the model is balsa wood. However, if you have hardwood handy don’t hesitate to use it. It may mean a few more hours work on the construction, but the time lost there will be made up when it comes to applying the finish. Hardwood, of course, also makes a more durable model.

Beginning with the main hull, cut out two blank shapes from 3/4-in. thick balsa or hardwood. Then cement them together lightly to obtain the desired thickness of the hull. Roughly shape the hull to a symmetrical outline with a whittling knife, using the cross section templates as a guide. When complete, sand the hull to the desired final shape.

At this point the wheel or hydro-ski axles can be assembled and installed. Before doing this, it is first necessary that the shaped hull be pried apart for their installation. Both the wheel and hydro-ski axles are bent from 1/16-in diameter wire. The bottom half of the hull is then recessed to take the axles and then the two halves of the hull are cemented together with the axles in place.

The skis for the water version are cut from approximately .020-in. thick brass and soldered to axles. Try to obtain a similar angular setup to what we have shown, as we have tried it this way and know it works fine.

The engine nacelle mount can be cut out from 1/8-in. plywood or laminated from two 1/8-in. thick hard balsa sheets. Shape it to a symmetrical piece as was done for the hull; then recess the top of the hull V8 in. and cement it firmly in place.

The engine nacelle is blanked out from two 1×2-in. balsa blocks cemented lightly together just as the hull was. Here again the shaping procedure is similar to that of the hull. When this phase has been completed, pry the two halves apart and hollow them out approximately as indicated on the plan. Then mark the position of the firewall and cut the two halves across at that point. Since only about ^ in. or less will be lost in cutting, just remove the difference from the cowl portion to account for the Va in. thickness of the plywood firewall.

Before cementing the two nacelle halves together all necessary cutouts for air, fuel, needle valve and cylinder head will have to be made. This is best done by first cementing the firewall in place to the lower shell and cowl, then mounting the engine permanently in place. Next check the top shell and cowl portion against the engine installation for the exact location of the required cutouts. When the assembly has been completed, recess the nacelle to fit on the mount and cement it in place. All that remains is to add such fixings as the canopy, tail piece, exhausts, bridle hooks for tether and the 3/16-in. hard sheet balsa or hardwood side fairings.

Before attempting to apply a finish, the next phase is to fillet all joints with Plastic Wood to obtain greater strength and a better appearing model. After this is done, give the model a final smooth sanding.

If a glow plug engine is used, remember the finish will have to be fuel proof. Begin by applying three to four coats of sealer, sanding smooth between each coat. Then apply three to four coats of clear fuel-proof dope. The colored dopes should be of medium consistency when applied.

Brush on at least five coats and, when dry, rub down the finish with a fine grit rubbing compound such as Duco No. 7 to obtain a high gloss.

In testing the models, particularly as extensively ‘as we did, we undoubtedly experienced all that you will in operating your own car or boat. If you are free-running the car, be certain that the engine is offset about 2° to the right as we indicated on the plan. The reason for this is there is a natural tendency for the car to veer to the left due to the propeller’s rotation. This force is known as torque. Now it may be necessary to use a little more or less offset, but this will best be determined while the car is being tested. In all probability your air-car will have to be tethered for lack of space. Braided wire of .015 in. diameter and 50 feet in length will do. It, in turn, is fastened to an .040 in. diameter wire bridle strung between two hooks. For a center post, drive a big nail or spike into the ground.

If you are testing the air-boat, the first thing you should do is add a little right turn to the rudder, even if you have offset the engine to the right. Make all your test runs from moderate to high speeds so that the model will quickly get up on the skis and not dig in and porpoise back and forth. In launching the model, keep the bow out of the water and follow through with a gentle sweep of the hand. About the most troublesome thing that might occur is a dunking if the turn is too sharp. Remedy: decrease the turn, dry out engine, run it and let her go again. Your efforts will be well rewarded.
BILL OF MATERIALS
Quantity Dimension Use
1 piece 3/4 x 4-1/2 x 26-in balsa or hardwood Hull 1 piece 1 x 2 x 18-in. balsa Engine nacelle.
1 piece 3/16 x 2 x 18-in. balsa or hardwood Side fairings.
1 piece 1/8 x 3 x 18 in. balsa Nacelle mount, tail piece Miscellaneous: 1/8-in. plywood firewall; 1/16-in. dia. wire for axles; 1/4 in. O.D. tubing; celluloid canopy; 1-3/4-in. dia. wheels for car or ,020-in. brass for skis; 1-1/4 in. dia. spinner; .020 to .049 engine; fuel-proof cement; fuel-proof clear and colored dopes; Plastic Wood; wood sealer.

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Intergalactic Space Control Panel

A fascinating, safe, electrical toy for junior space travelers.

By Robert Brightman

“GEE, Bob, when are you ever going to finish that control panel for me?” When your youngster starts off on a tack like this and keeps it up for a few weeks there is only one way to keep peace in the family. And that is to finish the job. The control panel as it is called by my son and all his friends is one of the most fascinating toys a father can make for his boy. Essentially it consists of a six-volt transformer, a series of toggle switches and miscellaneous lights, bells, buzzers and meters.

The first step is to rummage through the spare parts box and amass all the electrical parts you can possibly use. Visit your local radio shop lor the necessary transformer to convert 117-volt alternating current into harmless six volts. As you can see from the wiring diagram, two lengths of bus bar along the bottom of the box form common connections for various parts.

It is a good idea to first assemble all the parts you are going to install and then drill and cut the necessary holes in the sloping front of the control, panel. Of course you can do this with the box assembled, but you will find it much easier to do this before it is finished.

The switches are wired so that they do not turn on the lamps directly above them. If they did, operation would be too easy. As every parent knows a small boy always likes to do things the hard way! Wire them so that they turn on the lamps or bells farthest from the switches. The voltmeter is wired across the six-volt posts of the transformer and will of course always register six volts. The milliam-meter is wired in series across one of the lamp circuits or can be wired in series with one of the secondary leads of the transformer.

The more controls and switches the merrier. You’ll find that after a while you may want to add more devices. Simple enough, just remove the back and go to work. The earphones and corresponding jack were in fact such an added improvement. The jack is merely connected to a flashlight battery. Flipping a switch turns on the juice so that a clicking is heard in the phones. The two knobs shown are rheostats to dim two of the lights.

Another added innovation is the series of banana jacks on both sides of the panel. The upper two on the left are connected to the secondary of the transformer so that a source of six-volt alternating current for testing is readily available. At least two switches must be turned on before any of the lights will work. The first switch turns on the line current to the transformer. This is rigged so that a 7-1/2-watt pilot light glows when it is on “on.” The next switch completes the circuit in the secondary of the transformer. At this point any one of the various other switches can be turned on to make the lights blink, bells sound, buzzers burp and pandemonium reign.

Note the automobile curb feeler. This is hooked up to a buzzer and looks like a miniature antenna. Touching it of course causes the buzzer to sound—only when its switch is “on.” Such secondary switches are a constant source of delight to a boy and his friends. Sometimes the buzzer will work and sometimes it will not, depending-of course upon the switch position.

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Lightning in Your Hand

EXPERIMENTAL MODEL OF A VAN DE GRAAFF ELECTROSTATIC GENERATOR CAN DELIVER OVER 100,000 HARMLESS VOLTS

By Loren W. Gay

NUCLEAR physics, the unpredictable baby of the sciences, is about 50 years old. For the first two thirds of its short life it crawled patiently along on all fours. Then, without bothering to walk, it started to run. Just where it’s running to, no one knows, but it has already revolutionized man’s conception of his universe without even stopping for breath.

One of the mileposts in this swift race was the original of the electrostatic generator shown here. Neither surprising nor dramatic in its origin, the device was invented simply because it was needed: physicists wanted a controlled source of high-voltage D.C. in order to bombard the nucleus of the atom.

In 1931, Dr. Robert J. Van de Graaff went back to first principles to build a machine capable of delivering nearly 2,000,000 volts. Instead of rubbing amber and silk as the Greeks had done 2,000 years before, he revolved an endless belt in contact with metallic brushes.

The remarkably powerful model described in this article was designed chiefly as a laboratory-demonstration instrument. It is very simple in construction, and its exposed lower section permits a clear view of operation as well as effects. Before starting to build, procure the roller shafts, ball bearings, and the bakelite tube. If these vary from the dimensions given, you may have to alter some of the other specifications so that the parts will fit together properly.

Hard composition board was used for the two sides of the ground-pulley housing. Saw two pieces roughly to size, clamp them together, and drill and jigsaw the windows, slots and holes in both at once to insure perfect alignment. Slots for the pulley shaft should make a snug fit to prevent vibration, and the slots that will hold the ground-inductor glass must be cut so that the glass will be perfectly parallel to the silk belt and in light contact with it. It may be easiest to cut the glass first and fit the slots to it.

Cement and screw the base, sides, tube, and the two lower wood rings together. The belt tighteners and the uprights for the sphere pulley are also made of composition board clamped together and finished in pairs.

For the rollers, use a good dry wood that is not subject to warping or cracking. Rough them on the lathe, then screw to the faceplate a scrap piece of 1″ stock, and in it turn a hole that will make a tight press fit on one end of the roller. With the pulley chucked firmly in this hole so that you can work on the free end, turn a centered opening just large enough for the ball bearing to be pressed into place. Bore the shaft clearance hole part way through, using a skew chisel. Repeat these operations on the other end, and complete the shaft hole with a drill.

Prepare the other pulley in the same way. Test both rollers to make sure that they run true. Press the bearings and shafts in place, and clamp one shaft tight between the lathe centers. Belt the pulley to a motor so that it will spin on its bearings, and carefully turn the wood down to a uniform diameter of 2″. Turn a groove in the ground pulley for the driving belt; the sphere roller, of course, needs no groove. If the pulleys are out of true in any respect, it will be worth while to discard them and try again. Quality ball bearings good for a speed of 6,000 r.p.m., with an outside diameter of are recommended.

When assembling the pulleys on the shafts and on the machine, use washers and short pieces of metal tubing to space them out between the supports. Align the rollers with extreme care, and cement the upper ring on the tube.

Pure silk ribbon would be the ideal choice for the belt, but you’ll probably have to settle for rayon. Set the tighteners to allow take-up, place the ribbon around the pulleys, and cut it to size, allowing about lap. Remove the belt, cement the ends together, and clamp the lap between blocks overnight. When the mechanical parts are in satisfactory running order you can proceed with the electrical parts—the brushes and inductors. Inductors are made of sheet aluminum or similar metal, cemented to glass plates. For the sphere inductor, cut a 2-1/4″ by 2-1/2″ piece of aluminum, bend it to a right angle, and cement it to a 2-1/2″ by 3-1/4″ sheet of thin window glass. Both are then cemented to the edge of a piece of composition board which is slotted to fit between the pulley-supporting uprights. Position this piece so that the glass plate will be parallel to and make light contact with the belt. A brush, which must make electrical contact with the inductor, is bolted to the same composition-board strip, and touches the ribbon at the opposite end of the roller. The sphere brush completes the upper assembly; it is located directly behind the inductor and is separated from it by the ribbon and glass.

To assemble, install the sphere brush, and drop a loop of the belt through the bakelite tube; then slip the inductor assembly in place between the uprights, and place the sphere pulley and shafts in the retaining slots. Insert the ground pulley through the belt, and adjust and tighten to run true. The ground inductor and its brush are made in one piece and cemented to the lower glass plate, which is placed in slots in the housing and held firm by wood disks screwed to the case to overlap the edges of the glass.

Brushes are made of sheet aluminum or copper (medium-size variable-condenser plates will do nicely) and short pieces of extraflexible stranded-copper wire or tinsel. Drill an even number of small holes parallel to one edge and spaced about 1/4″ apart. Loop a length of the wire through each pair of holes, and bend the metal back on itself to clamp the wire in place. Trim the edges to a straight line. Brushes should be cut to come as close to the belt as possible without rubbing or catching appreciably.

The sphere is a 7″ metal map globe with an opening 4″ in diameter cut in the bottom. File the edge of the opening so that the globe fits the groove in the upper ring; if the fit is good, no other fastening is needed.

Shellac or varnish all wooden parts of the machine; avoid paints, since some pigments are metallic and will reduce efficiency. When the generator is ready for trial, screw it to a solid base and belt the lower pulley to a 1/4-hp. motor so as to drive it at about 3,000 r.p.m. Connect the copper ring and the ground brush or its terminal to a good external ground.

With the motor running, touch the belt lightly at the “charging point” with a rolled edge of celluloid or photo negative. Friction will knock free some of the electrons in the belt, imparting a positive charge. The missing electrons, however, are immediately replaced by the inductor brush, creating a potential between the latter and the ground brush. Between these oppositely charged plates, the glass acts somewhat in the manner of the dielectric of a condenser. Free electrons are attracted from the ground onto the ribbon, which promptly carries the negative particles upward through the tube and into the sphere. Three or four complete revolutions may be necessary to build the charge on the sphere inductor to its saturation point, after which most of the electrons are carried around to the sphere brush where, by repulsion of the sphere inductor, they are kicked off into the metal globe. The celluloid charging sheet may then be removed and the generator will continue to build its own cycle.

Once the sphere is fully charged, a number of interesting effects may be observed. Some are illustrated on these pages; others may come to you as a bit of a surprise. If yon venture close to the generator when it is in proper operation, the tingling sensation you may feel will probably be due to hair standing up on your head or forearm. You can draw a spark to your finger or to any metal object held near the sphere. In a darkened room you will be able to see the static electricity streaming from the ground brush onto the belt, and from the ground inductor up over the glass plate to the belt, or from one side of the belt to the other.

Measurement of actual voltage is extremely difficult, so no attempt was made to obtain a proper rating of this unit. Under favorable conditions the spark effects that are observed suggest an output in excess of 100,000 volts.

Favorable conditions, by the way, include a dry climate, since moisture encourages the charge to leak off into the atmosphere. If you live in high, dry territory, you can get results the year round. If not, you’ll have to do your experimenting when the weather man gives you the nod, or when winter’s steam heat cooks the moisture out of the air.

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How to Put a Ship in a Bottle

Making a full-rigged model that folds so as to enter the neck

By E. ARMITAGE McCANN

“HOW did it get there?” is the question always asked when a ship model in a bottle such as shown in Figs. 2 and 3 is placed on exhibition. You will observe the curious minded examining the bottom of the bottle to see where it was cut to admit the ship, or they will even inquire if the bottle was blown around the ship. But there is no fake about it; everything goes through the neck. With patience and determination, anyone can make this curious and always mystifying type of model.

First, get a clear glass bottle and clean it inside and out. If the neck is large, the work, will be easier; if small, the result will be more intriguing.

Although any kind of ship can be made, this work was in fashion among the clipper ship sailors, therefore a clipper, especially as it is long and slender, is well adapted to the purpose. We shall describe a full-rigged ship. It will not be exactly to scale, but the closer one can keep to the correct scale, the better the result.

Larger drawings, which will make the work considerably easier, can be obtained by sending fifty cents for Popular Science Monthly Blueprints No. 121 and 122 The hull is slightly more slender than the usual shape and cut off a little below the water line. It should occupy not more than half the neck of the bottle. The top should be cut into so as to leave the bulwarks standing; this also gives room for the masts and gear. The bottom should be hollowed as shown in Fig. 5. Paint and varnish the hull to any clipper ship colors you desire; usually, just black and white with red or green below the water line. Deck houses, lifeboats, and steering gear can be added if desired.

Since the hull will later be set in putty in the bottle, you must ascertain what the distance will be from the deck, when in position in the putty, to the inside of the bottle, so that the masts may be as long as possible yet not too long to stand upright.

The masts may well be in one piece, with steps cut in them to represent the lowermast, topmast, topgallant mast, and royal mast. Make them as slender as you can with sufficient strength to allow them to be strained on after the necessary holes have been drilled. Straight grained hickory, birch, or maple is suitable. These suggestions apply also to the bowsprit and jib boom.

The yards, spanker boom, and gaff are nicely rounded little sticks, tapered to the ends.

The principle of getting the ship in is merely this: All the masts have to fold down on the deck and then be erected when in the bottle by means of the hauling stays.

Each of the masts should have little tops and crosstrees of wood, celluloid, or fiber—and caps as well, if you like. Above and below the crosstrees of the foremast, holes pass through what appears to be the division between the lowermast and the topmast (see Fig. 4). Also drill the fore-and-aft holes as indicated for the stays, as well as a small hole for the futtock shrouds below where the top comes, and holes for the lifts.

The mainmast will be drilled in the same way, with the addition of athwart holes for the mizzen braces. The mizzenmast needs no holes for stays, but has to have them for the main braces as well as one each for the spanker boom and gaff. At the lower end each mast is slightly rounded, and a small hole is drilled for the hinge wires.

If you make the masts of three separate spars, they must be firmly joined. In that case, the shrouds and backstays will pass between them instead of through small holes as in the model illustrated.

The bowsprit has three vertical holes for the head stays, and the boom and gaff each have one hole at the mast end. All the spars may be white, black, or varnished.

The next step is to rig her up, outside the bottle. Two or three different thicknesses of thread should be used—say No. 50 black thread and No. 70 white or natural.

Fix the bowsprit firmly into a hole in the bow and rig it as shown in Fig. 4. These ropes can be hitched to the boom and pegged into the hull.

Fasten the yards to the masts in their correct positions by first tying a thread tightly around the center of the yard with a double knot abaft and then carry the thread around the mast, so that they will remain in position, yet can be turned to lie along the masts (see Fig. 5).

The spanker boom and gaff should be tied to the mizzenmast with the thread through the drilled holes.

STARTING with the mizzenmast, hinge each mast to the deck by carrying a wire through them and down through the hull, twisting the ends together underneath. You should be able to turn the masts down flat on the hull. Fasten the stays and reeve them through the hull or through the next mast and then through the hull or jib boom , as indicated in Fig. 4, leaving the ends long enough to pass out of the i bottle with plenty to spare.

The end of the mizzen topmast stay is pegged to the deck at the stern; then the stay is hitched around the boom and gaff and hitched again at the crosstrees. This will prevent the masts from coming too far forward when hoisted. Raise the masts and hold them in position by pegging the forestay where it comes out of the hawse pipe.

The easiest and neatest way to set up the rigging is to bore holes through the hull into the opening beneath as shown in Fig. 5. Thread a No. 9 needle with the heavy thread and start by pegging the thread end in the foremast hole; then I reeve through the mastheads and holes until all are up and tight when the mast is in position. The lifts and braces for each yard can be rigged as one. Start at one yardarm with a knot, reeve through the masthead, and knot to the other yardarm. Then, for the braces, reeve through the hole in the other mast or through the hull and carry the thread back to the first yardarm. The lift part of these lines should be painted black. All these threads must slide readily through their holes. Rubbing them with wax helps. The completely rigged model is shown in Fig. 6.

You may give the model topmast shrouds, rove through the top and a hole below the yard, and if you care to take the time, you may also add ratlines (steps) of very fine silk, although this is rarely attempted.

Now ease up the forestay, lay the yards along the masts, and lay the masts down on the deck. Make sure that all will go into the neck of the bottle, but do not let the model slip through. Draw it out and see if the masts will stand up again and the yards swing across. Then fold them down snugly once more.

Fasten the bottle with a clamp as shown in Fig. 2 so that it will not slip about while you are working on it. Put a layer of blue or green colored putty in the bottle after adding a little varnish to make it more tacky and to insure that it will dry firmly.

Sit in a good light and slide the hull with its gear into the bottle (see Fig. 1). With a long, stiff wire, press it into the putty sea. Untangle the end of the stays which extend from the neck and, still holding the model down, pull them one after the other, but be careful to do all the straining on the lower stays. At the same time, help the masts to rise with a bent wire. This operation is shown in Fig. 2.

When you have all the masts up, fasten the threads to the neck of the bottle, outside, and put a touch of glue where they come out of the hawse pipe and through the jib boom. Next, use the wire hook to swing the yards into position.

After the glue is dry, cut the lines off close with a sharpened wire, such as is shown in Fig. 7.

Additional picturesque touches can be added by inserting a lighthouse on a rock, a pilot boat or tugboats, and one or more fishing smacks in the water alongside.

As the ship is to be without sails, one or both anchor cables should come from the hawse pipes to the water.

Occasionally a bottle model is seen with sails, such as the one illustrated in Fig. 3. While the principle of assembling a model of this type is exactly the same, the addition of the sails, which are made of thin, flexible paper, complicates the work.

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Workbench Award Winners…

THE winner—all of ‘em! The six projects shown on these pages were the best Workbench Award entries received during the month. A five dollar check and a Workbench Award Certificate is being mailed to each winner for his prize project.

If you are a workshop fan then why not let us know what you’re doing? Send us a picture plus a letter describing your project and if your entry is one of the monthly winners you’ll receive our check and Workbench Award Certificate, which incidentally, is suitable for framing. If your entry is not one of the published winners you still may win our handsome Certificate of Merit. Past winners of Workbench Awards may submit new entries, but the photos must be of a new ‘project. Clear snapshots will do but wherever possible glossy enlargements are preferred. We like to see your creations—but we also like to see you, so if at all possible submit a photograph of yourself with your project. Enclose sufficient stamps for return postage and mail your entry to:

MECHANIX ILLUSTRATED Workbench Awards. 67 West 44th Street. New York 18. New York.

Working from his own designs, Carl W. Mikan, of Trafford, Penn., made this control-line model twin-engine transport. It has a wing span of 5 ft.-7 in. and weighs 11 lbs. with one-half pint of fuel aboard. Two Ohlsson and Rice .60 engines with three-blade props provide the power. Featuring a tricycle landing gear, the plane was framed up in usual manner, then planked with 3/32-in. balsa. It took 435 hours to build.

Photo-Fan Andrew Rohaly, Jr., of Beverly Hills, Cal., used Mi’s Plan No. P-2 when he decided to make a parallel-arm enlarger. Mrs. Rohaly says. “My husband has found so much pleasure in work ing with Mi’s plans. The enlarger was made from the following ingredients: an old bed, a waste-basket, a lye can, a pineapple can, an 1897 camera that cost $5, an old felt hat, and accessories picked up around the shop. The total cost was approximately $10 and the enlarger does excellent work up to 14×14 in. We both spend several nights each week printing pictures with it. Thank you for your good plans and interesting magazine.” And thank you Mrs. Rohaly, for the opportunity of sharing with you your pleasure in your husband’s craftwork. He is indeed lucky to have a spouse like you to work alongside him at the same hobby.

Jason Petroelje. of Holland, Mich., is another model-plane builder. He writes, “Enclosed is a picture of my Navion. I made it from Mi’s Plan No. 369. This is the first time I have used one of your plans. I found it very easy to follow. I have just started your Cessna 140 (Plan No. 380). The gal holding the model in the picture is my wife.” You’re another doubly lucky guy, Jason. Congratulations.

Boat fans will recognize the unusual project at the left as being an outboard-powered catamaran. Dick Oldham, of Pittsburgh, and Don Zimmerman, of McKees Rocks, both in Pennsylvania, are the proud builders. They got the idea for the boat from MI. The hulls are belly tanks and are held together with 1-in. pipe welded inside and out. The seats are made of Masonite and wood and supported by angle-iron braces wrapped around the pipe that goes through the tanks. Propulsion is provided by a 6-hp. outboard motor. Ex-GI’s will immediately realize that the model for the unusual paint job was the lowly voracious shark.

Ed Beyer, of Los Angeles, has two sons: eight-year-old Tommy and five-year-old Jackie. He devoted four months of his spare time in making this midget hot rod for them. He tells us. “The boys are wonderful drivers and it’s great fun to watch them whip the little car around. The materials cost a little over $100 and the car weighs 150 lbs. and stands 21 in. high. The engine is a 3/4-hp. Briggs with an automatic mercury clutch. Two V-belts and pulleys give a 16 to 1 gear ratio, allowing a speed of 16 m.p.h. The frame is welded up from 1-in. tubing.”

Frank M. Konrad, Jr., of Bridgeton, Mo., takes pen in hand to write, “Here is a picture of a bobsled I built recently in my spare time. It is 9 ft. long and has knee-action runners. It also has two headlights, a bell, brakes, and it steers perfectly. It has a seating capacity of five people. We had lots of fun last winter, coasting down hills at 30 m.p.h.” And we bet you’re having lots of fun with it this winter, too. MI is picking up the tab for a round of hot coffee (or other liquid) for you and your four passengers—we’re sending you a check for $5 and a Workbench Award Certificate. How’s about an invitation to go bobsledding this winter? Only one thing we’d rather do. and that is go to Florida and bask in the sun (Fla. Chamber of Commerce please note.)

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Universal Cable Adapter

By Art Trauffer

Built into a typewriter ribbon case, this adapter permits over 50 combinations of cable connections.

WHEN the writer finished making this adapter he started to count the different combinations of connections that can be made with it, but when he reached 50 he gave up. Certainly, 50 is not the limit for this versatile and easily-made adapter. If you build one of these you will save much time and trouble when joining together various types of connectors in radio and electronics experimental and test work.

To provide a degree of shielding, the adapter is built in a 2-1/2″ by 1″ metal container for a typewriter ribbon, but any similar metal container with a friction lid will do. The enamel coating on the outside of the container was removed with sandpaper and scouring powder.

The illustrations show how the two 5-way binding posts, and five of the jacks, are mounted in a circle on the friction lid. The “Tiny Jack” is screw-fastened in the center. The exact placement of the parts is not critical—just arrange them for convenience and good looks. Instead of drilling the mounting holes the required size, the writer found he could do a neater job by drilling small holes and enlarging them to the required size with rat-tail files. However, the four small holes for the “Tiny Jack” are easily drilled as required— use a No. 44 drill for the two mounting screws, and a No. 31 drill to clear the two pin holes in the jack.

All of the parts are wired in parallel, and the wiring is simple because the “ground side” of most of the parts are automatically connected together when the parts are mounted onto the metal lid of the can. If the inside of the metal container is coated, be sure to scrape the metal clean at the places where the parts are supposed to contact the metal lid.

If your metal container isn’t quite deep enough when the container is closed, simply raise the friction lid a little and then solder both parts of the can together with some solder spots.

PARTS LIST

2 5-way binding posts.

1 single-hole mount phono pin jack.

1 standard microphone chassis connector.

1 miniature microphone chassis connector (Switchcraft).

1 standard open circuit phone jack.

1 miniature phone jack 1 “Tiny Jack” (Lafayette MS-284) 1 round metal container with friction lid about 2-1/2″ wide and 1″ deep. (Carter typewriter ribbon case or equiv.) 2 2-56 or 2-64 round head machine screws long with hex nuts for “Tiny Jack” Misc.—Few assorted lockwashers, few inches #22 hookup wire

Car Touch-Up Sprayer for 25c

BEFORE you buy an expensive spray gun and compressor, try an artist’s fixative atomizer, available for 10c to 25c at art and drafting supply stores, model shops, and at many hobby and craft shops. Used by artists and architects to spray their pencil and chalk drawings with fixative to prevent rubbing, this gadget can perform many small painting jobs, using only lung power.

It works on the same principle as any compressor-type sprayer, with you supplying the compressed air. A jet of air is forced across an orifice, creating a low pressure area which draws the paint mixture up the vertical tube. As the paint comes out of the tube, it is literally “blown into bits.” The atomizer can be cleaned without disassembling—merely use a pipe cleaner dipped in thinner (C).

Of the 3 types shown (A) the type that comes mounted in a standard jar top is most handy where the same kind of paint is used repeatedly. However, the simple, 2-tube affair with a folding joint is preferable, as it can be adjusted to give a coarser, faster spray merely by bending the tubes closer together than the normal right angle (B).

Generally, any paint of the right thickness for brushing can be sprayed in this manner by adding to it an equal quantity of thinner. If the spray seems thick and clotted, add more thinner. The more thinner used, the finer the spray that results, but too much thinner will make it “run.” Too little thinner will make it too difficult to blow. Use alcohol to thin shellac, turpentine for enamel or oil paint, lacquer thinner for lacquer or for model airplane dope, and water for casein paints. Otherwise, use whatever thinner is recommended on the paint can. Stir or shake the mixture often during use, to prevent settling. Always spray out-of-doors if possible, and on a windless dry day. Breathe through a water-dampened handkerchief if spraying indoors for any length of time. Prop up the object to be sprayed so that it will not overturn during application.

There is no limit to the number of paint jobs that can be done this way: automobile retouching, model airplane doping, shellacking, furniture retouching—in short, any job where your brushing skill is inadequate, or where fast-drying paints are difficult to brush on without leaving tell-tale brush-marks. However, it is not advisable to try to paint your entire car by lungpower; a fender or two is enough to try, at least for one “blowing.” A final word of warning: Don’t try a plunger-type insect sprayer. The spray will not be uniform, and you cannot aim and push the plunger without missing the spot you want to hit.—Noble D. Carlson.

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DOORBELL HARP

By R. J. DE CRISTOFORO

THIS doorway harp will produce a merry melody at the front entrance to your home every time someone enters or leaves. One friend remarked that it should serve as an excellent deterrent to salesmen, since its sounds would distract them long enough for you to shut the door!- Be that as it may, the harp never fails to prompt a “Who’s playing the guitar?” from visitors, and is a good ice-breaker when welcoming guests.

Before beginning construction of the harp, make a full-size pattern by enlarging the squares (Fig. 2), and use the pattern to obtain the outline of the body and to locate the various parts during assembly. To cut out the front and back pieces (parts A and B, Fig. 2), first, tape the blanks together, then cut both at the same time on the jigsaw or bandsaw or by hand with a coping saw. Cut out part C, then make the inside cuts on parts B and C by taping them together and cutting at the same time, or by making the cut-out first in part B (Fig. 3) and using as a template to transfer the outline to part C. Sand the inside and outside edges of part C carefully, then glue it in place on part B and clamp.

To get the outlines for the dividers (parts D, E and F, Fig. 2), set them in position on the back piece of the harp and trace the curved outline with a pencil. Cut slightly outside the line and attach to the back (part A) with small nails and glue (Fig. 4).

Make upper and lower bridge (parts H and J, Fig. 2) and attach to front piece (part B). If perforated hardboard was used for part B, insert the screws through convenient holes. Otherwise, drill and countersink for them.

Apply plenty of glue to mating surfaces of front and back assemblies, and clamp until dry. To obtain a smooth contour, use a drum sander on the inside curves and a disc sander on the outside curves.

To make edging (part G), cut a piece of pine 2 in. wide, then resaw to get a piece as close to in- thick as possible. Sand this carefully, then apply a full coat of contact cement to one side. Coat the perimeter of the harp with contact cement also. Allow cement to set for about 20 minutes to a half hour (check with instructions on label of can), then place parts in position carefully and press them together (Fig. 5). Trim off excess and sand smooth. Part G can be made in two pieces if you prefer, butt-join ted at the bottom of the harp, or a suitable veneer can be substituted for the pine.

Finish the harp according to the material used and the effect desired. Colorful flat enamels are good for a gay Pennsylvania Dutch appearance, while stain and varnish are required if you’ve used a fancy veneer and hardwood plywood for the top.

Insert the music strings through the #40 holes drilled for them in parts H and J, pull as tight as possible, then thread through holes drilled with a #50 drill in the #5x-5/8-in. rh screws (Fig. 2 detail and Fig. 6). Turn each screw as much as necessary to keep the wire taut. Make the cover for the string screws (part K) from two pieces, nailed and glued together, or cut it from solid stock. Screw and glue to parts C and H (Fig. 2).

The wooden balls can be turned on the lathe, but 1-in. dia. wooden beads are easily available in a toy store. However, most of these have holes drilled through them which will have to be filled with dowel. Drill #40 holes in beads or dowel filler for the string, then attach the strings to part K with escutcheon pins, spaced 1 in. apart. Space horizontal centerlines of balls about 1-1/2 in. apart.

Finally, attach two small picture frame hangers on the back of the harp and suspend from two upholstery tacks on the back of the door, where it is all set to play a welcoming tune.—End

This Novel Martin House Is Built to Resemble Zeppelin

Edited by A. NEELY HALL

BIRDS ought to appreciate this latest design in apartment houses, built to resemble a Zeppelin. To make it, secure nine pieces of one-inch white pine and saw them into 10-sided partitions as shown in the drawing below, the middle partition being 12-1/2 inches in diameter and the others tapering down to 6 inches. A 3/8-inch hole is bored in the center of the pieces, which are then spaced equidistant along a bolt feet long. Central partitions and nest trays are installed as shown. Front and rear tips of the house are shaped from solid wood, and the fins from thin boards fastened to the ship with screws. Narrow pieces of tin, hinged at one end, are placed over each apartment; these may be lifted up for cleaning out the interior. Canvas is used to cover the Zeppelin. Pieces of strap iron projecting through the apartments serve as supports for wooden porches. The Zeppelin engines are made of large spools with the ends streamlined, and propellers shaped out of tin. A coat of aluminum paint applied over two or three coats of outside varnish finishes off this house.

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“Bombs Away!”

THIS lively game will give you all the thrills of knocking the daylights out of an enemy city with well-placed “demolition bombs” without the least danger to the bombardier, although the area below is bristling with antiaircraft guns.

The bomber (Figs. 3 and 4) slides on a revolving arm supported by a central post (Fig. 2) and is moved by hand until it is over target selected. By looking through the bombsight with its cross-wires the airman can get a direct line on target and release marble “bomb” by a hand lever. Forward of the low wing is the bomb-bay, a 1/2 in. hole bored down through solid wood fugelage. Midway the wood is slotted to receive pivoted bomb-release lever. At rear of wing is bomb-sight, a piece of metal tubing set in a hole bored at an angle has been properly adjusted (Fig. 5). Suspend a small plumb-bob, such as a .22 bullet, by a thread from center of bomb-bay, and sight through eye-piece. Bottom of bob and line of vision along sights should coincide. Move brad slightly up or down in hole in tube to adjust, then solder brad in place.

Paint on platform buildings, tanks, bridges, etc., or construct 3-dimensional subjects designed to collapse or topple over (Fig. 6). Beveled roofs cause end walls to spread under a direct hit, theoretically wrecking the building. Trains, boats and bridges are balanced on a narrow base and full over under a direct hit. The barrage balloon, precariously balanced on a wire loop, is easily knecked down. A rim around the circular platform prevents bombs from rolling away. Streets of the city (Fig. 1) are painted gray, river light blue, railway black, buildings in appropriate colors or camouflage, and unoccupied spaces green.

Each bombardier is supplied with a dozen bombs of one color, different colors for each player. Tally correct number of points (see Table A) for various targets; the largest number of points are for the most difficult targets, which, of course are the smallest. When a hit is made on a hospital, school, church or library, the bombardier loses points, as indicated. First bombardier to tally 151 points wins the game.

Now you can organize a bombing squadron and let the small fry fire away without your having a care in the world about any real damage being done.—Hi Sibley.

Fun with an Old Spark Coil

By RAYMOND B. WAlLES

ALTHOUGH producing a spark only about three-eighths of an inch in length, an auto (Ford) spark coil can be made to produce a brilliant stream of sparks, about two inches in length, by interposing small flakes of graphite throughout the gap. This is easily accomplished by dusting flake graphite on a tacky varnish card through which are fitted two machine bolts or binding posts for contact with the secondary terminals.

Trick cigarette papers can be made, by holding the book type of papers in the spark stream of a coil. The sparks will perforate the paper; so that a cigarette rolled with it will not draw no matter how hard it is puffed.

“Jacob’s ladder” operates well on a larger-size spark coil. This “ladder” consists of two stretched upright wires, spaced about half an inch apart at the bottom, and about an inch apart at the top. When they are connected to the secondary side of a coil, sparks will run up the wires, forming a ladder of fire.

A luminous character cut from metal foil can be made to give a brush discharge which is extremely interesting and pretty. Three sheets of glass are taken and, between the bottom and middle glasses, a sheet of tin foil is placed and connected with one secondary terminal. The character, say a letter or club insignia cut from tin foil, is placed between the middle and the third sheet of glass and connected to the other secondary terminal. This set-up works well on a small auto coil.

If an upright metal plate, about eight inches, is mounted on one secondary terminal and the coil operated, a neon lamp will light when placed as much as eight inches from the coil.

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Mechanical Flying GOOSE Decorates Radiator Cap

For novelty in radiator ornaments, you’ll have to go a long way to beat this mechanical flying goose. As you speed along in your car, an ingenious arrangement of mechanism in the bird causes it to straighten out and flap its wings to simulate a real live goose in flight.

WHILE your car is standing still this wild goose isn’t so wild. He perches sedately upon the radiator cap surveying the world with a glassy eye. But as soon as you start up and shift into high he flattens out his tail, stretches his neck forward and begins to flap his wings as if he were going somewhere, and going there in a hurry.

There is not a staggering lot of work on this bird, but it is important that all moving parts operate freely. With the exception of small brass rod, a short piece of tubing to fit over it and some sheet duralumin or aluminum, all materials can be picked up in your work shop.

Start with the body. The original was made from a block of sugar pine in. thick, 2-1/2 in. wide and 4-3/4 in. long. The general shape and inside carving is shown in the underside view in Fig. 1. In hollowing out the body an expansive bit, hack saw and chisel will do the work nicely. A certain amount of fitting will be necessary later when you install the mechanism of neck, wings and tail.

As the wings are first in importance, make and install them before the other parts. The phantom view, Fig. 3, shows how the wings are installed. Cut the wing plane or blade as per the squared diagram, Fig. 3, from sheet duralumin. Tin will do if you have not the lighter material, but it won’t function as smoothly. On the underside secure a section of 3/32 in. brass rod by means of fine wires. You will not be able to solder to duralumin.

Now make a universal joint of a short section of brass tubing soldered to a piece of tin cut as indicated in Fig. 3 for the wing to operate in. This fits into the slot in the side of the body, and is fastened to it by means of the bent ends of the elevating axis driven into the wood.

The principle of operation of the flapping wing is known as “feathering,” and is practically the same as the movements of a sculling oar used at the stern of a boat. This action is illustrated in Fig. 1. Note in the first position that the wing tip is down, but the leading edge is elevated. Thus the air current causes the wing tip to rise. When it reaches the top limit of the second position, or rather while approaching it, the crank arm inside the body is brought against a wood stop, which tilts the leading edge down, and thus the air current forces the wing tip down again. This flapping operation continues as long as there is a fair wind. The rubber band snaps the wing into proper position as soon as the crank-arm passes the center line.

It is necessary to have the brass rod, or crank-arm shaft, fit nicely in its tube bearing and also to have elevating axis work without much play. Tension of the rubber band will be determined by experiment, as will the location of the wood stops. Bind the rubber bands to the crank-pins with thread and apply model airplane cement also.

Tin will not do for the tail on account of its weight. So large an area must necessarily be above the axis that either duralumin or aluminum must be used. Even at that it must be counterbalanced with a good-sized piece of lead, for this weight must also keep the head erect when at rest, in spite of the fact that the latter, as well as the neck, is made of soft balsa. Added weight can be had by using a fairly heavy wire or brass rod for the connecting link, as illustrated in Fig. 2. It is necessary to swing this link low to clear the wing mechanism. Light piano wire is used for the link between head and body. This is a necessary feature, for otherwise the head would merely lop down in lifeless fashion when the neck is pushed forward. Loops in the piano wire are made by twisting two or three turns around a small nail driven into the workbench.

Use pins or long brads for the axes of head and neck, and be sure the holes are large enough for the parts to move freely. A neat counterbalance weight for the tail is made by rolling a cylindrical piece of lead in an extension of the former, as shown in the drawings. When air currents force the tail to a horizontal position this weight moves up into a recess of the body shown in Fig. 1. Set your goose on a standard of galvanized wire to clip around the radiator cap, and give it a try-out before painting. If the wings flap too high or too low, or both, make the necessary adjustment by using thicker wood stops. You may need to change the tension of the rubber bands for smoother action.

After tests are made, by all means give your goose the very best paint job you know how. Give all wood parts a white ground-coat, and sandpaper smoothly when dry. The bird should, of course, be taken apart for the painting. Next, with a comparatively dry brush—that is, without paint dripping from it—touch in the brown feathers until only the wing tips are left white. Also leave the breast white, as well as the underpart of the body, a portion of the neck and a spot on the side of the head, as shown in Fig. 3. Black, glass-headed pins cut off to about in. are used for eyes, and they certainly give this lively fowl a determined look.

With a first rate paint job this radiator ornament will cause much comment, and if your friends call it a wild goose chase, there is fascination in the fact that while you never really catch him, he never actually gets away from you.

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Simple Small TRAPS will Catch Winter Game

By HI SIBLEY

These old time favorites among trappers are simple and humane. They will trap pets for your menagerie.

Simple materials, a little time, a little patience, and you can have a good string of traps of your own!

There is a lot of good sport in trapping small animals, especially when you make your own traps. Besides, one never knows just what sort of varmint he’s going to catch and that adds a thrill or two.

With one exception these traps all take their quarry alive and uninjured, and they may be kept for the home menagerie. The diagrams illustrate their simplicity of construction. Any one of them can be built with hammer, saw and jackknife, or a shovel.

Probably the oldest type is the pitfall, which is used to this day by natives of the African and Siamese jungles for big game. In fact, a recent motion picture film recorded the trapping of a half grown elephant in this type of trap. For the young American, however, a fox or coyote is probably as large an animal as he may expect, unless he wants to tackle the mountain lions in the coast ranges.

The advantage of the snare and sapling trap is that it swings the victim up out of the way of other animals who might devour it and also prevents its gnawing its way to freedom.

This type is more spectacular in action than any of the others, and works beautifully. Select a limber sapling in the game country, attach a stout cord near the tip and draw it down to locate position of release mechanism. Drive a stake (A) firmly into the ground if there are no exposed roots handy, and about 12 inches from it, toward the tree, anchor a limber green twig with a notch near the upper end (C) as shown in the diagram. Now cut a cross stick (B), about 12 inches long, sharpen one end to engage in the notch of (C) and smooth the other end so that the cord loop will slip off when the trap is sprung. From the sapling suspend a soft copper-wire snare-noose so that it hangs four or five inches from the upright stick (C) which holds the bait. To prevent the loop from swinging about, put in light stakes against the bottom in such a manner that they will not interfere with its action when the catch is released. A semi-circular row of stakes around the bait makes it impossible to reach it except through the snare-loop. The bait should be tied to the stock (C). It is well to wear gloves.

The “squirrel” trap is suitable for rabbits and gophers as well as squirrels and chipmunks. Make a box 15 inches long and 6 inches square, with one end and the top left open. The top, with the end attached, is swung on an axis about six inches from the closed end. This assembly should be a trifle narrower than the inside of the box so that it will operate freely.

The rabbit trap: In a good-sized packing box cut holes about 6 in. wide by 7 in. high opposite each other. Dig a hole deep enough to set the box with the bottom of the openings flush with the ground. Make two wooden tunnels or gangways with open tops about 18 in. long to fit loosely in the box openings. These are set a little more than halfway out of the box so that the outer ends rest on the ground, but the weight of the rabbit entering the box to get the bait will tilt the outer end up and slide the captive into the box. Small blocks are nailed to the underside of the tunnels to prevent them sliding into the box with the rabbit.

For small rodents the wire cone trap is a baffling device. They squeeze into it freely in quest of the bait, but every time they try to get out, the wires close on them. Bore a hole in the end of a wooden box. Around the edge of this hole insert a series of short wires that are stiff but with plenty of spring. Bend them toward an apex at the inner ends, just so they are about half as far apart as the diameter of the hole. The wires offer very little resistance to the quarry until it attempts to get out. , The “Figure 4″ trap is an old and tried device, but nevertheless a very efficient one. It is very good for birds, but burrowing and gnawing animals can make their way out without much trouble, unless the, box is well weighted and the trapper arrives soon after the catch. This can be made with only a jackknife from sticks about inch square. Larger or smaller will do as well. Details of trap are shown at left above.

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Money Making Toys For Christmas

By JOSEPH H. KRAUS

How to Make Money from These Plans OF four items illustrated here, only the “Human Roulette Wheel” requires much work. Three are well fitted for profitable sales, the roulette wheel and the illusion box most so. The track circuit for toy trains is an ideal window display. Sell your services to local toy stores, offering to arrange for them an automatic display which is mysterious and attracts attention. The light twinkler makes an excellent display, but is best for home use.

The illusion box is a form of an old magical trick; the other items (including the illusion box circuit) were originated by the writer of this article, and home workshop users have full permission to use them.

A well-made illusion box should find sale at from $10 to $25, depending on size, and whether the control is included. Your window-trimming skill can be sold to advantage by including in it the automatic train circuit, for five to ten dollars, at least. The human roulette wheel can be made for as little as one dollar (without motor) but models for amusement and game purposes should bring ten dollars or more, depending on size and finish of product.

• RADIO parts can frequently be used to increase the effectiveness of Christmas tree illumination, and similarly, for producing small-scale illuminated signs of the moving, or changing, type. An example will be found in Figs. 1, 2 and 3. Here part of a regular selector switch (such as used for switching shortwave coils) is used for progressive controls of a group of lights. If an old switch is not available, a similar construction may be made from a piece of fiber, a sweeping brush-con tact arm, and a number of contacts circularly arranged to be wiped by the brush as it passes. The brush itself is fastened securely to a shaft, to which a rather large wooden pulley is firmly attached. A brush for contact presses against this shaft. On the comparative sizes of the wooden pulley and the pulley on the motor, depends the rate of the flicker, or rotation of the brush. The larger the pulley on the shaft and the smaller that on the motor, the greater will be the speed reduction. The motor speed can be further controlled by a rheostat. Fig. 2 shows a simple construction for the home use; Fig. 3 presents the side view; and Fig. 1 shows the circuit diagram where the storage battery is used to furnish the power.

A variation of this construction uses a fiber brush which passes between two contacts, thus opening the circuit and extinguishing the lights on that line. By such a system, all of the lights are on with but one exception; whereas in the illustration here given, all lights are off except that to which the circuit is completed by the motor driven brush.

When the railroad track circuit, illustrated in Fig. 4, is properly set up, the short train stops until the long train clears the track. At the proper moment the short train dives across the intersections. However, the short train running on the shorter track may sometimes continue to run around its oval for half a dozen times without stopping. On occasion the trains are so close together that spectators will gasp while awaiting the crash, but the crash does not occur. Sometimes one train will nose out the other, sometimes barely clear the tail end. Everything depends on the length of the section A-B, the length of the section C-D, and whether one or two sections of rail are placed between A or C and the cross-over. In this track circuit, insulated tracks must be used; such as those used for operating signal systems, in which the center rail and one outside rail are insulated, are an absolute requisite. At the same time, insulated connections are used on both outside rails at points A and B, and on the insulated outside-rail section at points C and D. After the track has been set up, place the short train on the track, so that the engine is on the crossover, in the direction of travel. Apply current and allow the train to travel around the track at full speed. Naturally, when it reaches the track section between A and B there is no current on the outside rails: consequently, the train coasts to a stop. If the train, under its own momentum, continues across the insulated section AB, the length of this section must be increased to prevent this. Now, place the long train on the other track; it continues around until the circuit is closed from one outside rail, through the wheels of the car, to the other outside rail, and thence, through a short piece of wire, to section A-B. Now, the short train will start to get under way and will be operating at full speed at the time the last car passes the cross-over. While the insulator at C is shown near the cross-over, it is preferable to insert this either two or three sections away from the cross-over, so that the short train will not hit any of the cars of the longer train. Naturally, if the short train is equipped with a magnetic remote-control system, the system must be plugged or cut out entirely, to prevent the progressive selector from reversing the motor and thus making the train inoperative. It might also be suggested that this exact circuit need not be followed precisely, as long as the principle is used: thus, the trains could run on two ovals, one inside the other, with the shorter train crossing near the end of one of the oval sections. Signal lights may be cut into the circuit to operate directly from the trains and tracks, producing a more realistic effect. As mentioned originally, this layout is a positive attention-getter for a window display, uncanny in its performance and entirely automatic.

The “illusion box” illustrated in Figs. 5 and 6 is a simple, square, wooden box provided with a light, a diagonal partition, half of which is a sheet of glass (preferably plate) fitted into a dovetail in the partition, and a small framelike extension which projects 3″ from the opening. All dimensions for the construction are given in Fig. 6. An automobile bulb is fastened on either side of the partition; an empty vase is placed on one side of the glass, and one exactly similar, containing flowers, is placed on the other side. The inside of the box is painted a dull black. When the bulb in front is lighted, the rear one out, the reflection of the empty vase will be seen in the glass. When the front bulb is turned out and the back one lighted, the vase behind the glass will be visible. This elusive change from one vase to another can also be used for changing an empty box of cigars to a full one, a chicken to an egg, a dollar bill to a five-dollar bill, or any other conversion desired. Little more need be said about the construction. Reference to Fig. 7 will give the circuit for the control of the lamps, which employs an ordinary Christmas-tree flasher, two bells connected as shown, and the automobile lamps A and B (which may have to be of different candlepower). The circuit of an ordinary bell is completed from one binding post through the coils, thence to the contact, and back to the other binding post through the metal strip on the hammer. It is necessary that the wire from the magnet to the contact be cut.

The original toy illustrated in Figs. 8, 9, 10 and 11, is a small scale reproduction of the “Human Roulette Wheel” found at the seaside amusement resorts. A series of circular discs are caused to rotate in the directions indicated by the arrows; a celluloid doll, weighted with lead, slides down on the rotating discs and, after being tossed back and forth, finally bounces out through one of the openings. There is no way to predict where the doll will make its exit. The construction may follow the lines illustrated in Fig. 11. A large pie-pan is turned upside down; two phonograph discs, 12″ in diameter, are cemented together to form a pulley wheel. A bearing is soldered to the exact center of the under side of the pan (or tray); and the shaft, wheel and middle turntable are fitted in position. All turntables are 3″ in diameter, and may be of plywood, turned out to shape, or metal discs cut out of 3/16″ sheet iron. A shaft is fitted to each in the exact center. If the builder decides to use iron discs for the turntables, the friction drive shown in the upper right corner of Fig. 11 will serve. It has the advantage that any of the discs may be stopped by hand, with little danger of the fingers of a small tot being accidentally injured by the rotating pieces. However, if this toy is carefully finished, there is no danger of any such accident.

If wooden turntables are to be used in the construction, the most advisable method of drive is the belt. In this case, the shafts of the turntables extend through the bearings for a distance of one inch, and are fitted with small V pulleys. Two small pulleys are fitted to the driveshaft (the center turntable), and two cords run to the pulleys, in sets of three, as the diagram illustrates. A small toy or other motor drives the toy.

After this part of the construction has been completed, solder in the small fences, cut from strips of brass, and bent as shown in Figs. 9, 10 and 11. These fences are not more than an inch high, and serve to keep the dolls on the turntables for a greater length of time. In fact, if the openings are rather small, it is not unusual for the dolls to zigzag back and forth for as long as 15 minutes.

Any suitable chute is built, and so situated that the dolls will slide down and fall on the center turntable.

In order to convert this toy into an interesting game, each exit is painted a different color. The entire toy is given a coat of enamel, and the dolls must now be prepared. Small dolls about high are used to represent the people who normally form the cargo of the “Human Roulette Wheel.” While jointed celluloid dolls are preferred because of the antics of the tiny performers, others will answer just as well. Along the seam of the celluloid doll a cut is made, and a small quantity of lead shot inserted. The seam is then either cemented with a cement of acetone and celluloid, or cloth or a rubber band is used to close the opening. Small bits of cloth must now be sewed to the dolls; or the discs will merely slide under the weighted dolls and there is little action. The color of the cloth should match the color of the openings; six dolls should be prepared; and bets may be made at odds of 5 to 1 that the doll will not emerge from the colored opening assigned to it. The cloth produces sufficient friction to produce a lively toy, which never performs the same way twice in succession.

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A BOY’S DREAM COME TRUE

Give a boy a tree house and he can have all the adventures of a safari in his own backyard.

For adventurous little boys, a tree house offers many delights. It is a hideaway, a place to store secret treasures, a camping-out spot. From it one can see without being seen. It can be reached by ladder only and it is relatively inaccessible to adults. The one shown here also has certain nautical details to please would-be seafarers. It was designed and built by Gerald Repp of our Art Department for his 7- and 9-year-old sons and has proved itself rugged enough to .withstand both the elements and the wear and tear of the young. Our woman’s day Workshop has made complete plans and specifications for building the house, in a tree or on the ground, using simplified construction methods. The materials are inexpensive and readily available.

The house is 5′ x 6′, an A-frame with walls of exterior plywood. The deck is 19′ long, comes to a point like the prow of a ship. It is built of 1″ x 3″ subflooring nailed onto a framework of 2″ x 4″s and has railings of 1″ x 3″s.

The best way to handle the project: (1) build the framework of the A’s and the deck in your yard or workshop; (2) hoist up the deck frame first, then the A-frames, via rope, to a helper stationed in the tree. Then nail on the house walls, deck flooring, posts and railings. The finishing touches: fresh paint, a screen door and screening at the open sides of the A’s.

SIMPLER. ON-THE-GROUND VERSIONS
If you do not have suitable trees, or do not want to go through the acrobatics of getting the house up in a tree, you can build an on-the-ground version, with or without deck and railings. The house alone, resting on a framework of 2″ x 4″s with tongue and groove flooring nailed on, can be successfully tackled by any amateur. It takes little time, no real skill, is built of inexpensive materials. The only tools needed are in the simple hammer and saw category.

BOYS! MAKE LEAD SOLDIERS BY THE DOZEN

Mould Your Own Army — Band — Athletic Teams

With the new Gilbert Electric Kaster Kit, you can easily make a whole regiment of lead soldiers. Color them, too, with Kaster Kit paints, so they look just like the finest soldiers you can buy. Extra Kaster Kit moulds make football and baseball players, a military band, cannons, animals and other exciting models…Earn extra money by selling Kaster Kit models to your friends.

Kaster Kit operates by electricity. Safe and easy. See it at your nearest toy store. Complete with i mould and 24 pigs of metal $4.95.

GILBERT KASTER KIT

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TIN-FOIL SCULPTURE

How One Man Makes Good Use of a Common Wrapping Material That Most of Us Throw Away

THIRTY years ago, as a child, Paul E. Tichon began collecting scraps of tin foil. He still does. In the meantime, every scrap he could lay his hands on he has converted into hundreds of delicately hand-wrought pieces of “sculpture,” some of which are illustrated on these pages.

Zebras, strange birds, dogs, deer, gayly bedecked knights in shining armor astride well-modeled horses, and dozens of other creatures line shelves in his Akron, Ohio, home, while one of his most prized creations is a framed three-dimensional picture in tinfoil relief showing a wintry woodland scene with fawns grazing in the foreground.

A lifelong fondness for studying animals and a natural artistic aptitude combined to give Tichon his remarkable skill in modeling. Unlike sculptors who use tools, he forms his figures entirely by pressing the metal foil into desired shapes with his fingers. Metal foil has certain advantages other modeling mediums lack, according to Tichon. It is yielding enough to be pressed into shape, yet it does not spring out of shape when pressure is removed. And, as it crinkles under pressure, it becomes stronger just as corrugated metal is stronger than sheet metal.

A capable artist familiar with painting in oils, Tichon quite naturally tried combining his two talents. The result was more than satisfactory. Now he hand-paints his zebras, for example, in true-to-life colors and patterns which, as he jokingly puts it, enable people to distinguish his zebras from his jackasses. Paint solved another perplexing problem for him—the obtaining of lifelike faces. Details of eyes, nostrils, and other features applied with artists’ oil colors did the trick.

Tichon’s animals are usually made of only two or three pieces of foil which he first cuts to approximate sizes. They are pressed, modeled, bent, and folded to form the figures, then crimped together. So agile are his fingers that he can model a deer in less than five minutes. He has trained himself so thoroughly that he can make from memory in a surprisingly short time a realistic tin-foil figure of almost any species of bird or beast you can mention to him.

Radio Store Provides Free Clubroom for Wireless Amateurs

IN the back of a retail electrical store located in the skyscraper section of New York City, there is a unique club-room for radio amateurs. A full set of radio receiving equipment has been installed with an aerial on the roof. Apparatus can be tested out in actual practice, and the visiting amateur is given the privilege of taking any piece of apparatus from stock to connect up and use as he sees fit. The employees of the store make no attempt whatever to sell goods to the amateurs using the club-room. Even if the visitor asks for information, it is given without any intimation that he is expected to buy.

Amateurs who live many miles apart and who know each other only via wireless, form a habit of dropping into the club and talking over their installations. If one has a new idea in hook-ups, there is a chance to test it out. If a newcomer wishes to learn the standard connections, there are blueprints on the walls. If a “club member” has a theory of radio to demonstrate, he can step to the blackboard and sketch it out with the other amateurs present giving criticism and argument. Sometimes, if one is lucky, one may meet some of the experts from the big wireless companies, and get the latest “dope” direct.

By promoting interest in radio, the clubroom has proved a moneymaker for the store. The goods sell themselves, for by listening to the conversations in the clubroom the beginner in wireless finds out what he needs for a first class station, and goes out into the store and buys it. He has learned the right name, too, and does not waste the clerks’ time nor compel the salesman to give a curtain lecture on electricity and magnetism every time a receiver is sold. Best of all, the clubroom gives the amateurs a chance to exchange ideas and stimulates their interest in radio.

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A “Down the CELLAR” Chem Lab

by FREDERICK O. SCHUBERT

Here are some interesting experiments you can perform with simple chemicals, with notes on building the beginnings of your own basement chemistry lab. More next month!

NOW that we’ve succeeded in shoving Andy, the grease monkey, and the rest of the “hangar gang” over a bit for the lab boys, let’s get together and make real use of our “chem” pages. It’s not going to be hard if you spatula wielders and test tube wrestlers will get behind and push the crate along. After all, it’s to satisfy you birds who like to fiddle with specific gravity and distillation rather than angles of incidence or variable pitches that we’re goin’ into the mechanics of chemistry.

The major part of you fellows undoubtedly have some sort of a workshop either in the basement, up in the attic or out in the barn. But to get under way we’ve got to give all the gang a chance to start from scratch. So, at the risk of being considered elementary, we’re going to start by talking about the “down in the cellar chem lab”

that we have designed. Perhaps you seasoned experimenters will catch an idea or two.

As you probably have noted already, no dimensions are given in constructing this lab. Your own best judgment—and the size of space available—will have to govern its construction. Too, the location of the nearest gas, electric and water outlets must be considered. Your own ingenuity will enable you to adapt these plans.

An ordinary kitchen table is perhaps the handiest to start with because it can easily be obtained. It is already equipped with a “drawer and can quickly be set up. The details of shelving likewise are simple and require no great detailed discussion. Enough to say that as your experiments continue and you add more and more equipment and chemicals, the value of adequate shelf-room will be appreciated. They may look empty for a while, but Oh Boy, when you get going!

Much of the testing and mixing equipment must be purchased. If you’re on good terms with the local druggist you can get him to order much of your stuff wholesale. Then—you can make a lot of it yourself.

Take the centrifuge. In recent years this piece of apparatus has saved much time in separating liquids of different specific gravity from each other and solids from liquids when they are held in suspension in such a way that they cannot be filtered. What formerly required days is now done in a very few minutes.

This you can make from an old phonograph. By extending the pin that holds the playing disc and equipping it with a double cross-arm that has slots for test tubes at all four ends you’ve got the finest centrifuge in the world. Wind ‘er up, throw the switch and she is off while you’re doing something else. Although the number of revolutions per minute is not as great as electrically operated machines, it will serve every requirement of the cellar chemist.

A piece of marble can easily be obtained from any junk-shop. This serves well as an ideal mixing board for pasty materials. Bottles, too, can be salvaged from the heap in sizes to meet every need. The same holds true with corks, wire for test tube holders and scraps of pure metals for lab work and analysis. The illustrations show how you can make your own alcohol lamp.

Among the equipment that you will have to buy are graduates calibrated in cubic centimeters, spatulas, mortars and pestles, glass tubing for stirring rods and droppers, funnels, scales, test tubes, filter paper, litmus papers, thermometer, hydrometer and a gas or electric hot-plate. To this should be added a pair or two of rubber gloves for working with acids and a good, substantial rubber apron. A number of good books on chemical experimentation, too, are not amiss for in them will be found much of interest and value.

The question of what chemicals and preparations to purchase is a difficult one to answer in this limited space. When it is considered that the average pharmacopeia contains more than 25,000 chemical preparations to which additions are made almost daily, we can be pardoned our wish to refrain from specifically stating that you should have this or that acid, powder or liquid. As we continue in our monthly rambles we’ll have plenty of opportunity of adding to the chemical end of our lab.

One thing in chemistry that is always interesting is the large number of tricks you can perform. Take the case of glowing pictures. They can easily be made by drawing a picture on white paper with a solution of 40 parts saltpeter and 20 parts of gum arabic in 40 parts of warm water. An ordi- nary pen is used and all lines should be connected. Extend one line out to the edge of the sheet and mark the spot where it runs off with a light pencil. When a burning match is held to this spot the design— formerly invisible—begins to glow and appear in brown.

There is another little stunt that will make a permanent display for your living room. It’s a chemical garden and simple to make. Prepare a small jar full of cold, saturated solution of Glauber’s salts and into the liquid suspend a kidney bean and a non-porous marble, stone or piece of glass by means of silk threads. Cover the jar and in a few days small crystals of sulphate of sodium will be seen radiating from the bean increasing it in size and giving it the appearance of a sea urchin. The non-porous body will remain unchanged.

An explanation of this stunt states that the bean appears to have a special partiality for the crystals, which is due to the absorption of water by the bean, but not the salt. In this way a supersaturated solution is formed in the immediate neighborhood of the bean and the crystals, in forming, attach themselves to its surface.

A good “weather vane” can be made from white blotters saturated in a solution of one ounce of cobalt chloride, half ounce sodium chloride, 75 grains of calcium chloride, quarter ounce of acacia and three ounces of water and left to dry. The amount of moisture in the air is roughly indicated by the changing color of the blotters. Rain is denoted by a rose-red tint, lavender-blue bespeaks dry weather and a bluish-red announces a change in weather conditions.

Speaking about the weather, here is a handy little weather glass that is even more accurate than the papers. Dissolve 2-1/2 drachms of camphor in 11 drachms of alcohol and 38 grains each of saltpeter and sal ammoniac in ’9 drachms of water. After mixing the two solutions pour them into test tubes and cork them airtight—or better yet, draw out the tube until only a pin hole remains. If you use the corking method run a red-hot wire through the corks so that you will have a very small hole about the size of a pin.

When the camphor appears soft and powdery and almost fills the tube you can expect rain and south or southwest winds. When the substance is crystalline expect fine weather with winds from the north, northeast or northwest. When only a portion crystallizes on the side of the glass, wind can be expected from that direction.

During fine weather the substance remains clear and at the bottom of the tube. When the substance begins to rise and a small star can be seen swimming around in the liquid you can be sure that rain is on the way.

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Automatic Cigarette Lighter in Ornamental Elephant

Smokers will find this little elephant both an attractive and useful ornament for their dens. Pick him up and an ingenious switch inside him automatically turns on an electric cigarette lighter in his neck. Put him down and the lighter goes out. Only a few inexpensive parts are needed.

THIS elephant is a vicious looking creature but he is useful as well as ornamental. Pick him up from the library table and he immediately “lights up” so that you can light your cigarette underneath his chin (if elephants have chins). When he is replaced on the table the “light” goes out automatically.

The elephant illustrated in the accompanying photos cost twenty-five cents at the department store and is made of plaster with a colored porcelain exterior. It is hollow, so there is plenty of room inside to install the lighting element and automatic electric switch that operates when you pick it up. Of course the plaster figure of a tiger or other beast may be used, and if care is taken to secure a duplicate, one figure may be displayed on each side of the fireplace mantel. As a suggestion, make a hole in the top of the second animal and use him for an ash receiver.

In making this elephant cigarette lighter, first drill a small hole large enough for the tip of a cigarette in the beast’s neck. To break through the thin porcelain, start the hole with a small drill and finish up with a round file until the aperture is large enough.

The plaster drills nicely, although undue pressure must not be used or it will crack.

There is a hole the size of a quarter already made in the elephant’s abdomen in course of manufacture. It is through this hole that the lighter element, the automatic switch and the wiring are introduced.

Fasten two short wires to a small 110-volt lighter element, which can be a replacement element for manufactured lighters. Solder cannot be used so the wires must be crimped to the element connections with pliers, as is done with a soldering iron element. Using the wires as a holder insert the element through the hole in the figure and work it around so that it is over the opening in the neck. When this is accomplished cement it in place by pouring a little plaster cement around the element case.

The plaster cement is made with one part water and one part sodium silicate (water glass) with enough plaster of paris to make the mixture about as thick as cream. An eye dropper is handy for placing the cement around the element.

For the automatic switch secure a one-dram glass vial, a cork and a small ball bearing that just fits the bottle. Run two short wires through the cork and spread the ends out like a broad “Y” as shown in the accompanying drawing. Place a little cotton in the bottom of the vial to serve as a cushion for the ball bearing, then insert the ball and finally the cork. The plug which holds the vial will close up the abdomen hole.

The drawing shows wiring arrangements. Connection from the elephant to the outlet box is made with silk covered wire. When the elephant is picked up to light a cigarette the bearing falls into the “Y” wires in the vial, closing the contact. The bearing returns to the bottom of the vial when the elephant is replaced on the table.

In carrying out the idea for providing a twin for the elephant, obtain another figure and use it for an ash tray. You can bore out a large hole in the beast’s back, using the file which you used for making the neck hole. Make the back hole large enough to hold a small tin receptacle, which should be inserted and secured with cement. A little paint of the same color as the beast’s back will smooth up the rough edges if applied carefully. Set this figure beside the other on your desk or mantelpiece.

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YOU CAN Make Your Own 4th of July Fireworks

by FREDERICK O. SCHUBERT

THIS month’s chemical section is dedicated to that noble and glorious purpose of celebrating the Fourth of July in noisy fashion—and with cannon crackers and colored fire that can safely be made in your own lab. However, before plunging into a pile of recipes and formulas it is necessary to warn you fellows to be extremely careful in preparing these mixtures. In themselves they will not blow up until brought into actual contact with fire or through extreme friction, but remember always that you are working with explosives—regardless of how mild they may be away from fire.

To overcome the dangers of friction it is well to mix your powders in small doses. A simple way is to put them on a sheet of fairly substantial paper and, by picking up two ends, rolling the powder back and forth as you raise and lower your hands alternately. But where you must use your pestle and mortar—watch out for friction!

One of the first things to prepare are the containers for the powder. These are best made from brown wrapping paper rolled several times around a broom stick. As each turn is made it is advisable to paste it down so that the shell will feel fairly solid. Eight or ten turns of paper should be enough for the average fire cracker. The length best suited is anywhere from six to eight inches. They can be made longer, but it is not advisable. After the cylinder is taken from the broom stick, insert an inch of clay in the base. Pack it in solid so that your powder will not filter through. The next step is to take several turns of tissue paper and glue it to the other end as shown in the illustration. A few turns of string will help too. You are then ready to fill in your mixture and place your fuse. Don’t pack the powder. Pour it in.

There are several ways of preparing the fuse. The easiest is to take soft cotton string a bit heavier than the kind the grocer uses in doing up bundles and soaking it in a solution of one ounce of saltpetre dissolved in a glass of water. It is ready for use as soon as it has been thoroughly dried. A fuse with a bit of sparkle can be made by using the golden rain formula that follows. The mixture is made into a paste with water containing several drops of glue. The string is thoroughly covered and left to dry. In using this be sure that no space remains along the cord that is not covered. Other- wise your fuse will burn out before it reaches the powder.

And now, here are the formulas. But remember, all the ingredients must be dry and powdered separately and then mixed on a sheet of paper, without friction. Always bear in mind that sulphur and chlorate of potassium will “go boom” when rubbed together. Keep the ingredients away from open flames.

A nice bright red fire can be made by using 20 parts of strontium nitrate finely powdered, six parts of sulphur, 5 parts of saltpetre and one part of lampblack. Your druggist can supply them all in powdered form. They may cost a few cents more that way, but it is safer than trying to powder them yourself.

In making golden rain the main ingredient is saltpetre. Nine parts of it are mixed with three parts of lampblack and four parts of sulphur. Your green fire contains two parts each of barium nitrate and chlorate of potash, to which is added one part of sulphur. White fire is made of 15 parts gun powder, 22 parts sulphur and 64 parts of nitrate of potassium, while blue fire is easiest made by mixing eight parts of chlorate of potassium with five parts of copper sulphate, four parts of calomel and 3 parts of powdered shellac.

One of the safest noise-makers to work with are the caps for pistols and canes. They are made by folding a small portion of a mixture of equal parts of chlorate of potash and sulphur into tin foil. The proper fold is shown in the drawing. They are set off by the force of the hammer in the pistol or cane, and are not dangerous because of the small quantity of powder mixture used. It is suggested that not more than a pinch be used for each cap.

For the fellow who wants to experiment with rockets and Roman candles the following formulas will come in handy. The rocket mixture comprises four parts of nitre, two parts of wood carbon and one part each of sulphur and meal powder. The meal powder acts as a diluent and is a fine brown or black dust. The Roman candle filling is made of eight parts of nitre, four of sulphur and three parts of carbon dust.

In burning colored fire, it is best to place the powder in a pill box and ignite it there. If you – experiment with rockets, you will want to construct a platform from which to launch them. A good idea of an efficient launching platform can be obtained from the drawing at the beginning of this article. A simple v-shaped trough of wood or metal, supported at the desired angle by a couple of props or legs, will do the trick. Of course, the angle of the platform will have a very great deal to do with the path taken by the rocket. Usually this angle should be at least 60 degrees to permit the rocket to attain a satisfactory height. A shallower angle than this will produce a flattened trajectory of the rocket which will not be as satisfactory as a sharper, higher path through the sky.

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BUILD THIS MODEL OF THE LINCOLN FUTURA

This superb scale model boasts front and rear lights, “turn” indicators, and electric drive.

By Paul Palanek

THE most revolutionary and advanced vehicle ever to be driven on public highways was given its world driving premier early this year. Benson Ford, vice-president of Ford, who drove the sleek low-slung twin Plexiglas dome Lincoln Futura for the first time on a public thoroughfare called it, “a $250,000 laboratory on wheels.”

Almost 19 ft. long, 7 ft. wide and only 53 in. high the Futura has a low silhouette and smooth flowing lines almost devoid of exterior ornamentation. Its all-steel body is a beautiful pearlescent, frost-blue white.

Our model to a one-inch scale reduces the 19 ft. Futura to a 19 in. model. This accurate scaling down was accomplished by using a factory drawing, received from Lincoln-Mercury. Not only have we attempted to capture the esthetic beauty of the Futura, we also made it a functional model, as it uses a tiny electric motor to make it actually run. It also boasts a set of head and tail lamps and “turn” indicators. In our opinion the Plexiglas canopy is the model’s finest feature.

The material selection for the body shell, is left to the whim of the modeler. The choice is either hardwood or medium grade balsa blocks. We decided to employ pattern makers’ pine. Shell halves are cemented using a good grade of cement, such as Weldwood glue. A C-clamp or two will hold the glued surfaces and avoid any possibility of shifting while drying. When dried, lay out the top and side views as indicated on the drawings and cut to shape. Let the saw cuts include the wheel cutouts. Sand the top deck flat in the general area of the canopy. Pencil-line all surfaces that blend with one another. An example of this is the raised trim bead that circles the lower half of the body, where the flat rear deck meets the inner sloping walls of the rear fins. Follow this simple procedure throughout the layout and carving stages. A wood rasp is a good tool to use if you are working with hardwood. Regardless of material a good set of carving and gouging tools are most important. A flat oil stone should be employed to hone the tools after short periods of carving.

The cockpit cavity is shaped as shown in the drawings and a 3/8 in. hole drilled to receive the steering gear. Spot drill a series of holes fore and aft, in the general area of the grill cavities. Finish this grill cavity with a slight radius on its edges.

Drill the holes for the lighting system. Bear in mind, the complete lighting hook-up is fastened to the inside of the body shell. Three hook-up wires lead from the shell to the proper chassis terminal posts. Check the wiring diagram.

Upon completion of the shell with all surfaces smoothed over, apply several coats of wood filler, about five should do the trick. Bear in mind the importance of filler, it is the foundation of a super finish.

Since few of us are fortunate in owning a paint spraying outfit, we chose the second best method to apply the finish, Krylon paint spray. The colors are Regal blue; aluminum for “chrome” and a white base. Spray the shell with several coats of white, allowing at least six hours between coats. Sand lightly, using fine sandpaper, wet with water. Other colors are sprayed on using tape to mask off the required areas.

The grill work is next in store, and is made from .020 in. celluloid, concaved, then cemented in place. This procedure applies to both front and rear grills. Space the grill rails, 1/16 in. apart. Along the lower inner surface of the body shell, secure four strips of 1/4 in. square hardwood to support the Plexiglas chassis.

Since the canopy is transparent, a steering wheel is needed. Using turned aluminum or wood, fashion the gear as indicated and mount in the hole on the dash. On the after deck of the shell mount the radio antenna. Here again, we use aluminum or turned wood. After installing the canopy, use silver masking tape to trim the canopy bubble and body surfaces. Complete the shell by adding the forward and rear light windows. Use red for the rear and frosted for the front. A coat of wax will preserve the finish and beauty of the car.

We used Plexiglas for the chassis for two reasons. It is easy to work with and it is an excellent non-conductor. The drawings show all details pertaining to layout and construction. The signaling light switch is wired to indicate left and right turns. To fasten the wheels, place a bit of solder at the end of each front axle after mounting the wheels. The rear wheels are bolted in place.

The entire electrical system, excluding the drive is a 24-volt hookup. It uses four No. 724 Eveready batteries wired in series. A Burgess battery powers the Imp six-volt motor. Mount the motor as shown. Shim to increase the friction between motor shaft and rear wheels.

Mounted in the center of the chassis is a pair of airplane type seats, fabricated from 1/2×3 in. sheet balsa. When completed, fasten in place using three No. 3 wood screws, 1/2 in. long. The seat assembly including chassis is sprayed a flat black. To complete the circuit between body and shell and chassis, fasten three No. 4×40 bolts and nuts as shown, to form posts to which the proper wire is fastened. Allow some slack on these wires. Once the chassis is complete and functioning properly, assemble, using No. 3 wood screws. Our Futura is now complete and ready for the road.

Forming The Canopy The crowning glory of the car is the bugeye canopy appearing on its prototype. With a little effort, care and patience, the reader will find it rather easy fashioning this Plexiglas enclosure.

We will employ the identical methods used in the aircraft industry, to make plane canopies. The materials required are wood, Masonite, some nuts and bolts and lastly the Plexiglas itself.

Proceed by shaping the male form of the canopy, that is the inner surface of the completed shape. Refer to the line drawings for shape and contour lines. Bear in mind that all surface and contour dimensions are kept 1/16 in. smaller to allow for the thickness of the plastic. The male form must be brought to a glass smooth surface, free of bumps or valleys lest they distort and mark the canopy. Apply several coats of hard shellac, allow sufficient time for drying before each coat. Use fine sandpaper and rub wet using water as the wetting agent.

The next item is the mask and stripper plates, both very important to proper drawing. The mask and stripper plates measure, 1/4x8x10 in. To hold the opening in the mask to a definite dimension, allow % in. clearance between the mask opening and the male form. The stripper must be fabricated with care and skill. Its opening is similar to the mask but is 1/16 in. larger than the male. This permits room for the form and Plexiglas to be drawn through. On the stripper, all sharp edges should be removed and a radius filed to permit the clastic to flow freely under pressure.

As will be noted, No. 10×32 screws se- cure the glass, between the mask and stripper. These have a two-fold purpose. They add rigidity to the mold and prevent the plastic from wrinkling when being drawn.

Complete the stripper by adding the hardwood restriction plate called the “bridge.” This will restrict the flow of Plexiglas and provide a definite line between both halves of the canopy. Bear in mind the in. clearance needed for plastic thickness. The three items, plastic, mask and stripper are drilled as shown, using 3/8 to 1/2 in. dia. holes. All are fastened with 10×32 bolts with washers under both head and nuts. The washers should be of sufficient diameter to cover the drilled holes.

To heat, we used a standard kitchen oven with thermostatic controls, keeping the heat in a 300° range. If little success is attained with the first pressing, try again.

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HOW to EXPERIMENT With ROCKET SHIPS

Home-made rockets can be easily prepared and attached to almost any model airplane for successful experiments in flying rocket ships.

By KENNETH B. MURRAY

IN THE experiment about to be described, a thirteen-year-old Michigan high school boy planned and constructed a regular model airplane to which was attached a home-made rocket. After considerable experimentation in balancing the plane and positioning the rocket a sufficiently stabilized arrangement was made and the plane tested out.

The plane was placed in the middle of a city street, other smooth take-off surface not being available, and heading into the wind. A match was applied to the fuse of the rocket. A large burst of smoke first started the proceedings. Then, with a loud hissing, the plane started rolling, gathering speed within twelve feet sufficient to lift it clear of the ground. The time of the flight was almost a minute, the larger part of this being after the rocket had exhausted itself. The highest point reached by the plane was approximately 20 or 25 feet.

. Other experiments with different types of rockets and a change in the upward pitch of the wings of the plane were made, and it was found that there was “practically no limit” to the height or length of the flight, the factors being controlled by the wing pitch, size, weight, power and durability of the rocket charge.

Inasmuch as it was determined that if the rockets are made in the correct manner there was no danger of an explosion even in inexperienced hands.

Although regularly manufactured rockets removed from a skyrocket stick and with the cone end removed assure one of success, the enjoyment of home manufacturing achievements put the home manufactured rocket plane in favor. Commercial rockets also present the difficulty of not being available in a sufficient number of different sizes and of different strengths. The home-made article can have incorporated in it the ideas of the builder and each can be made to suit the size and weight of the plane that it is to propel.

A light, tough cardboard should be secured and rolled into a tube of the desired length and diameter. The walls should be at least a quarter inch thick, and must be well pasted or glued. The powder is made of one part by volume, not by weight, of pulverized saltpeter, and one part charcoal. Each of these is non-explosive, but they must be pulverized separately. After pulverizing the materials, moisten the saltpeter, gradually adding water and mixing in a china bowl until it is a thick paste. The charcoal is then added a little at a time until all is well mixed in. To this is added about a tenth part of powdered sulphur. By the time that charcoal and sulphur have been added the compound will no longer be a paste but merely a moist compound. It should be spread out in a shallow pan and allowed to dry thoroughly, after which it is ready for use.

This powder is not explosive in the open air, merely burning slowly with much smoke. It must be confined to produce the power required to propel the plane.

Reverting to the rocket tubes, one end must be filled in with the exception of a small hole, half the size of a pencil. It was found that plaster of paris is suitable, as it can be poured into the end of the tube and allowed to set and dry well. A tightly wound roll of paper with a hole left in the center can also be glued tightly into the end of the tube.

The tube is next filled with powder. It must then be tightly stomped down until it is as compact as possible. Fill the tube to within an inch of the top with the packed powder and then stuff in some paper scraps moistened with glue until the end is entirely stopped up. The rocket fuse is made of a very small tube of paper, filled with powder and inserted in the opening in the rear, or propelling end of the rocket.

The illustrations show how the rocket is wired to the plane, care being used to find the center of balance. It must point downward slightly to avoid burning the tail of the plane in flight. A further precaution against the plane catching fire is to line the underside of the tail with a piece of cardboard, which will not burn through during the duration of each flight.

Place the plane on a level surface with the front facing into the wind. The igniting of the fuse is done from the rear.

There will be a burst of smoke and fire at first, and the rocket will quickly roar and hiss and propel the plane forward with amazing speed. It should leave the ground within a few feet if the balance is correct. The illustration shows the experimental plane just as it has left the ground.

No directions for the building of the plane are given as any flying airplane model, either a glider or rubber motored plane, should prove satisfactory.

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Hurdy-Gurdy

Cranking the Swiss music movement within this box makes the little begging monkey go into his dance.

By Elma Waltner

THE street organ grinder is a rare sight these days and it’s likely that most youngsters have never seen one. However, this little hurdy-gurdy, with its dancing monkey begging for pennies as the small owner grinds out a tune, will prove a popular toy.

The music is furnished by a Swiss music movement of the crank-handle type. Such movements can often be purchased at local hobby supply houses. If you can’t locate one in your own area, a sure source is Walter’s Modern Hobby Shop, 207 French Road, Utica 4, N. Y.

Construction of the hurdy-gurdy is simple, as is evident from the drawings. When the pattern has been cut in the front panel, back it up with a piece of bright-colored cloth. Then assemble the box with small finishing nails and glue, leaving the back off until the works are put inside.

Mount the music movement at the proper height within the box. The crankshaft is bent from a 1-ft. length of No. 9 wire. However, it is installed with only the U bend and the handle is bent after the wire has been passed through from the inside. The crankshaft is secured to the end of the music movement shaft with a coupling and the ends of both shafts are filed flat so that they will not slip after the screws are tightened.

The arms of the monkey are nailed tight to the body. The legs, however, are loose-jointed so that they will swing freely when the monkey bobs up and down. Push the supporting dowel stick into the monkey before driving in the nails which hold the legs to the body. Then the nails are driven in far enough to help secure the dowel but not far enough to bind the legs.

Use a plastic bottle cap for the monkey’s cup. Two holes are drilled through the side and a short length of copper wire is inserted for the handle. Then slip the cup handle over the monkey’s hand and cement the cup and hand together with household cement.

Install the monkey by slipping the slot in the lower end of the dowel over the U bend in the crankshaft. A small brad, bent over at the end, locks it in place.

The length of 20 inches for the leg of the music box is about right for most 4- or 5-year-olds. However, the length may be varied as may that of the neck strap. This strap is made of denim or other suitable heavy material.

Add a door knob to the side of the box opposite the crank handle to permit the child to steady the instrument. Finally, fasten the back in place with four screws.

Painting suggestions are given for the monkey, but best make the face tan in contrast to the rest of the body. Then too, the parts should be painted before they are assembled. The original box was gray, but a livelier color or combination of colors will appeal more to children.

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CLATTER GUN

There’s fun galore in store for the boy who has this realistic sounding Thompson machine gun. By Orlando Guerra AT practically no cost and in a very small amount of time you can convert a mailing tube into a marvelously noisy clatter gun. Most kids will love it.

A three-inch-diameter tube is best for the purpose, and it should be cut to a 14-in. length. The gun stock is cut from one-inch pine according to the pattern shown, then the tube is glued and screwed to it.

Noise is supplied by a 1/2-3-in. piece of clock spring or other springy strip of metal riveted to the lid of a one-gallon- size can of developer which happens to be precisely the right size for the 3-in.-dia. tube. (The bottom of an ordinary tin can may be used if it is cut to leave a half inch of the sides attached to it. But make sure that it also has a 3-in. dia.) A ratchet is cut according to the drawing from any 1/2-in. hardwood. It operates by plucking at the spring when turned by the handle, thus giving the staccato, machine-gun effect. The ratchet turns on a piece of 3/8-in. dowel (obtained from an old wooden coat hanger) attached to the handle.

Three-eighths-inch holes are drilled on each side of the tube and in the center of the ratchet. Insert the dowel in one of the barrel holes, through the ratchet (making sure that it is centered), then out through the second hole in the barrel. Then screw the ratchet securely to the dowel, and attach the handle and end piece.

Secure the noise maker to the end of the tube, but be sure that the spring is in between the teeth so as to allow the ratchet to pluck at it. Shellac and finish by painting the clatter gun in bright, contrasting colors.

For an added touch of realism, cover the front end of the gun tube with fly screening or any other fine mesh wire. Then attach a medium-size cork to it—just above the center. This will simulate a real Tommy gun’s small barrel opening.

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Animated Cartoons for the Amateur Cameraman

by HI SIBLEY

With your amateur movie camera you can make amusing animated cartoons which will give a new zest to home entertainments. In this article Mr. Sibley tells you just how to go about it to produce creditable animated cartoon films.

THE amateur movie cameraman has a broad field of experiment before him, and trying out animated cartoons will afford no little amusement.

Of course, the comical little figures we see in the theatres, with their exaggerated but still lifelike movements, are the result of long and painstaking experience, but the amateur, by beginning with the simplest ideas will eventually develop very creditable skill in this unique work.

Briefly, animated cartoons are ‘a progressive series of sketches — sometimes several thousand in a single reel—drawn upon printed paper backgrounds.

Suppose you want to show a man walking. The figures in the circle on the opposite page show the successive positions taken by the man’s arms and legs to simulate motion. Drawing the progression in proper relation is accomplished by placing the paper over ground glass under which is a light bulb, as shown in one of the illustrations herewith. The artist places sheet number one on the glass, and sketches in the first position of the man. Sheet number two is placed over the first so that the backgrounds of the picture, such as buildings, etc., register perfectly. Then the next position of the man’s legs and arms is drawn in, and so on.

This would seem laborious work to carry through several hundred pictures. True, there is considerable work, but on the other hand only the outlines need be drawn, and for brisk action they need not be carefully finished for even the most practiced eye can detect no flaws in a sketch that appears for but a fraction of a second. Dead blacks can be used for coat, hat, hair, etc., but no shading, for unless the shading lines are identical— or as nearly so as the action will permit—the result is a disconcerting blur.

The next stage is photography. The pictures, beginning with No. 1, are laid flat and the camera focused over them. Two exposures, or frames, are made of each cartoon. In commercial practice this makes eight separate pictures to the foot — the total passing in just one second! However, much footage can be gained by taking several exposures where the action slows down, having the man turn his head and look out at the audience with a perplexed expression now and then. This latter action can be used over and over again with the same set of drawings.

For general purposes a standard typewriter sheet, 8-1/2×11 inches, is suitable for the cartoons. This permits figures large enough to be drawn readily. A pen making a broad line, however, should be used, such as a ball point, or better, a regular lettering pen. Blank sheets of paper can be used for the first experiments, or perhaps backgrounds cut out of cardboard.

A simple feature for the beginner is a trick automobile, cut out of cardboard and having wheels, seat, steering gear and driver in separate pieces. This little machine can be made to do all manner of stunts—fall apart, blow up, turn somersaults, etc. Two sets of wheels should be made, one with black shadows on the disks and another plain. By alternating these the wheels will appear to revolve. The shadows, however, should be placed in the same relative position as the wheel advances. Clouds of exhaust smoke, can also be cut out of cardboard, in several sizes, and moved slightly farther from the exhaust pipe with each exposure, increasing the size in the meantime. Cutouts of human figures can also be made in a similar way.

In making cutouts it is important that there be no sharp corners or thin projections, as these have a tendency to curl and cause a shadow on the background. A first class two-ply, pen-and-ink bristol board is satisfactory material.

Cutouts involve considerable work but have this advantage in that they can be used repeatedly. One would think that a walking figure could be made convincing simply by having one leg move regularly in front of the other, in stiff-legged fashion, but on the screen a man would appear to.be blown along, swinging his legs like a pendulum. As a matter of fact, the actual motions of the legs in walking are very little like those we see in cartoons.

Because of its simplicity of outline a swimming fish is one of the easiest items to work out in a lifelike manner. He has no baffling feet to struggle with, and only his mouth, eyes, fins and tail need be animated. Foreshortening the body by gradual degrees makes him appear to turn toward or from the camera, as the case may be, and considerable footage can be gained by having him goggle his eyes and wave his tail, while the body remains stationary. Your fish can be made to swallow a Jonah, turn around, leap out of the water, emit air bubbles, or anything you want him to do with very little trouble. Figures in silhouette always show well in the screen.

For cutout figures running, a moving background is effective. This can be made up as shown on page 137, with graduation along the lower edge to indicate the degree of movement for each exposure. In this case the figure stays in the same place in the frame, legs and arms moving only, while the background is advanced a quarter of an inch for each exposure. Permanent backgrounds of this nature can be worked out in shading, either in lines or wash. They should not be too elaborate, however, for they will detract from the moving figure.

As a rule quadrupeds should be avoided in the beginning, for the amateur has four legs to contend with instead of two—and two are quite enough.

There are an endless number of subjects to experiment with, and as your skill develops you can work out a feature film of amusing incidents that have happened to members .of the family or to friends, and this could be made a splendid entertainment.

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Ancient War Machines

Replicas of some of the ancient engines of war make fascinating and educational model projects.

ALTHOUGH the advent of the jet plane, atomic gun and submarine has changed the aspect of warfare so considerably that it could hardly be recognized by anyone living a hundred years ago, primitive and ancient war machines still continue to fire the imagination of boys of all ages. Authentic replicas of some of the major weapons of the ancients make fascinating model projects, and with this in mind, MI asked model maker Eugene Thomas to specially build a set of these models and draw up easy-to-follow plans.

The five machines shown are the Catapult, Scorpion, Springal, Ballista and Tower. The Tower, the most important of the engines of war is first mentioned in Nebuchadnezzar’s siege of Tyre and Jerusalem in 587 BC. Other types of machines were used as far back as the siege of Troy in 1100 BC. Philip of Macedonia, 360-336 BC, also made extensive use of various types of siege engines. These Towers ranged from 70 to 150 feet in height and were moved on wheels of solid oak, twelve feet in diameter, three to four feet thick. Used for attacks against walls, they were so high that from their top the parapet walks of the wall could be swept with arrows and stones; drawbridges were then lowered from the tower by which the storming party could reach the top of the wall.

The Ballista, extensively used by Caesar, is a crossbow-type of weapon used for the discharge of small stones or arrows, mainly for direct fire. The Catapult dates from the same period but was used as a siege engine, throwing bolts or rocks at a high angle of elevation. Some of these machines were enormous, firing from 58 lb. (1 talent) to 580 lb. rocks at opposing walls, as mentioned by Marcellus. The range varied from 400 to 800 yards. Four soldiers were used on each side of the engine to wind down the arm until it was almost level with the ground. The missile was then inserted in the sling and the weapon fired by pulling the lanyard. The Scorpion also belongs to the family of catapults and got its name from the scorpion-like action of its arm. It was later called Onager (wild ass), comparing it to the kick of an ass.

The Springal, probably dating from the 3rd century BC, was one of the forerunners of the machine gun, firing a succession of arrows or burning spears. It is similar to the Polybolos, or Repeater-Thrower, invented by Dionysius at about the same time. The skeins that supplied motive force for all these engines were made of the sinews of animals, twisted raw hide, horsehair rope, and in at least one case, women’s hair.

The models are made from walnut stock and hand carved, giving them a hewn appearance just like their full-scale counterparts. A straight grained, knot-free stock should be chosen for this purpose. All stock sizes should be computed from the drawings before ripping to size. Tools needed are, a file, pins, Amberoid cement, small jeweler’s saw, carving knife and small electric hand drill; a vise and sanding block will also be found useful. If a lathe is not available, wheels may be turned by chucking them in a drill press or hand drill and sanding them to the required diameter.

Tower
Start construction by laying out dimensions on paper tacked to a work board. Cut all cross members and cement them to the uprights, using liberal amounts of cement. Siding strips are then made by cementing the 1/16×1/4-in. pine strips together and trimming them to fit into the required position. Add 3/16-in. sq. braces, dadoing all cross braces.

The sides are now completed and erection of the Tower can begin. Cut 5/8-in. stock to make the base, sanding a slight bevel at the bottom of the uprights to allow for the slant of the sides. Drill holes for the dowels and cement in place. While the cement is drying add the cross members, starting at the top; flooring and wheels can then be added. The drawbridge and roof complete the Tower. For the roof cement 1/16x^x3 in. pine strips together and cut four triangles with a 50° tangent to get the desired height. Develop the roof before cementing it permanently in place. To finish this, and all other models, two coats of clear lacquer are required.

Ballista
Hand-carved walnut stock, in., is used for the base. The 1-in. sq. post is then cemented in place, using 1/8-in. dowels and liberal amounts of cement. Add the angle and post braces after positioning them first for pegs. By using the pattern supplied on the drawings the trigger slides and trigger can easily be cut out. The whole upper assembly attaches to the base by means of a 3/16-in. dowel. Enough play should be given here to allow for tilting of the weapon. Nylon cord supplies the skeins. The amount of tension on the skeins determines the range of the model.

The Ballista is fired by sliding the trigger forward’ until it engages in the bow string. (For clarity the elastic bow string is left out in the drawing.) After engaging the bow string the whole trigger assembly is wound back and the brake pin inserted to prevent trigger from sliding forward. An arrow is inserted and the weapon is now ready to be fired by pressing down on the trigger. The mount rest supplies the necessary elevation.

As all the other models, the Springal is made of walnut stock, hand carved to give it a hewn appearance. The construction is simple, all steps being clearly shown on the drawing. The springboards were cut from 1/16-in. walnut, however, if lemon wood is available this is preferred. Nylon cord around the base secures the springboard.

The weapon is fired by inserting the trigger in the ring of the springboard and winding it back. Pulling on the lanyard releases the trigger which in turn frees the springboard. Three miniature spears are then driven against the target by the slapping action of the springboard.

Scorpion and Catapult
The action of the Catapult and Scorpion are similar, but there is a slight variance in design between the two weapons. The firing power of these engines is derived from the action of the sling which holds the missile. The sling can be made from cloth or soft leather. Engage the trigger in the hook of the sling arm and wind down by using the spanner as winder. Pulling on lanyard releases the sling arm, which in turn fires the small rock contained in the sling. The range is determined by the amount of tension put on the skeins.

The models are not drawn up to any definite scale since even the original weapons varied considerably in size. Depending on the size of the particular props you intend to use, you can arrive at dimensions to best suit your own requirements.

Balsa kits are available for these models. They are manufactured by the Authentic Reproduction Co., New York 60, N. Y., and can be obtained from War Machines, 5 Dairy Lane, Hicksville, N. Y. •