The ultra-simple engine projekt

This document describes how you can build a very simple electric engine that runs on DC from an ordinary siza A cell.
All you need are a length of enameld copper wire, some mounting board, a magnet and a battery. For assembly you may need some tools, I used some universal pliers and some cyanoacrylate glue. This engine will be very weak but gives a pretty good insight into the working principle of electric engines and can be finished by any more or less skilled person, especially kids, within an afternoon. But beware, this can be nevertheless result in injuries like burns or cuts, so play safe!

View of the finished device. The coil, the magnet and the place for the battery on the left can be seen.
All you need to do is the following:
>wind ca 10 turns of the copper wire on a 5cm dia form, wrap each end around the resulting coil one time on opposite sides.
> Then you need 2 supports the coil can easily turn in and two stiff wires that touch the leads protruding from the center of the rotor.
> At the wire ends coming from the coil remove the isolation from the copper wire on only half of the circumfence.
> Assemble these parts together with the magnets as shown in the picture.
leave some extra wire from the contact wires to make a simple battery holder as shown in the picture, you can use two matches to keep the battery from rolling away.
You may want to attach something not too big to the rotor to make any movement better observable.

When you feel everything is in the right place insert the battery and stand clear ;-)
Because this is something like "half phase" rather than polyphase our engine needs a little help to start, gently help with the first few turns, then the motor should run by itself.
If it does not tweaking is indicated. rearrange the realtive position of the coil and the unisolated areas you made in the previous steps. Check the connections to the battery and especially between the moving and the stationary contacts that guide the current to the rotor.
If it looks like it wants to run but can't maybe using 2 cells instead of one will do the job.