Comments on: “Perpetual Motion” Machine Makes Novel Window Display (Jul, 1931)

By: Rick Auricchio

Rick Auricchio — Thu, 14 May 2009 04:53:34 +0000

Ah, thanks, Kent. I didn’t realize the visual effect of the bottles as supports without visible connections.

By: KentD

KentD — Thu, 14 May 2009 02:25:50 +0000

Yes, the acid is to make the water conductive, and in only 2 of the bottles. I suspect salt would work, or maybe a less dangerous acid. But battery acid would work. The electrodes need to be lead or good stainless steel or they will corrode quickly.
This is not so much like a stepper motor as it is a linear induction motor, similar to that used in maglev trains, or some amusement park rides. The roller coasters that launch you usually use them.
The hardest thing to get may be the ball. My local junkyard is all out of steam engine governors. I think it might be best to find the largest steel bar you can find and scale the rest to that size. If you can find a ball the right size, you could use HO scale track. Use surplus solenoids for the magnets.

By: Toronto

Toronto — Thu, 14 May 2009 01:46:17 +0000

I thought the purpose of the acid was to make the water conductive, so there were no obvious wires going to the track.

By: Rick Auricchio

Rick Auricchio — Wed, 13 May 2009 23:55:20 +0000

Cool! This is like the grand-dad of a stepper motor!

They don’t really tell how to mix the acid solution, but I suspect modern electronics can provide everything we need without that stuff.

I’m thinking all that’s needed is a DC power supply with some form of current regulation; should be easy to create that.

By: Jake Hildebrandt

Jake Hildebrandt — Wed, 13 May 2009 23:22:58 +0000

This is REALLY clever! The sulfuric acid in the bottles is especially brilliant. I think I just may have to recreate this wonderful machine…