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Motors! Motors! Motors!
By George Foard
Those redundant video machines and audio tape recorders are a supply for useful electric motors. You can find them at flea markets, boot fairs, and local authority waste disposal sites (or 'tips'). The last video machine I found yielded 4 motors. I've paid not more than £1 for a u/s machine.
Arm yourself with assorted screwdrivers and wire cutters and you're in!
These drive motors are not 'can' motors. They are transformed down from mains voltage to, usually 9-12V DC, or battery driven at the same voltage, and they are reversible.
I have found them to be very reliable - they have to be by virtue of their original use! Some have brass or nylon-type armature bearings - the heavier ones have ball bearings - and they are powerful! Two that I have hold a worm on the armature shaft, bracketed to a worm-wheel (as installed) and you just cannot hold the worm-wheel shaft - it will burn!
Mount the motor in your model with 'Terry' clips of appropriate size. Primary drive is best by using a belt or band(s) straight off the armature shaft. Avoid gears. They will run, literally, all day without even getting warm, using a suitable controller on 9V DC - I've done it. If a motor does go 'phut' you can afford to throw it away.
Dimensions vary between 30-40mm in diameter and 15-40mm in length. The machines also yield assorted driving bands and belts.
For obvious reasons, avoid direct mains motors. If in doubt, get the motor checked by a competent TV or Audio repairer, rather than an electrician. Generally, the inscriptions on labels will not give you a clue. Stick to domestic machines - business or commercial outfits, to me, are an unknown quantity.
» This article appeared in the January 2002 issue of SELMEC News.