View Full Version : Spring wound motor...

05-04-2006, 02:14 PM
I have need of a small geared spring motor than can be wound up with a small crank.....needs to turn a 3/8ths inch shaft about 20-30 rpm for two minutes.....can't use batteries..
total power about the same as a small battery 1/4 inch electric drill...any ideas....

Bob Smalser
05-04-2006, 02:29 PM
I'd look for an old Victrola.

05-04-2006, 02:50 PM
I had thought of that and haunted a couple or three flea markets to no avail.....even considered disassembly of the magazine on my Calico to see how they solved the problem....it has a spring in the middle, a spiral groove around the central shaft to hold 100 rounds of 9mm.......a little crank to wind it up and apply pressure to roll it around.....
I need something to operate a valve underwater in an emergency...even considered a co-2 assisted drive...but....seals are a problem....spring drive seems better.....

Bob Smalser
05-04-2006, 02:55 PM
Those Thompson drum magazines are still available on the aftermarket, I believe.

But I'd call a few high-speed antique dealers and ask who repairs their Victrolas, as I'm certain there's a little old guy in a workshop somewhere that has a box of those old flat spring crank motors under his bench.

No way you're gonna make one rustproof, but parkerizing the parts'll help.

P.I. Stazzer-Newt
05-04-2006, 02:56 PM
Thorens used to make a very elegant clockwork shaver. you might gut the innards from.

Alternatively, you could try tensator - I have seen a number of constant torque spring motors from them.

Here is a page with contact details and an explanation - prod me if you need inside contacts.

05-04-2006, 03:02 PM
I'll e-mail a couple of these folks and see what happens...thanks fellers....

Keith Wilson
05-04-2006, 03:17 PM
30 rpm, 60 revolutions - how much torque?

Tom Robb
05-04-2006, 03:36 PM
Ma Bell, in the "good old days" of electro-mechanical central offices, used a spring wound gizmo to wind up paper punch-tape that recorded your calls. The paranoids were right. Ma Bell is watching you;)

P.I. Stazzer-Newt
05-04-2006, 03:49 PM

Has a pile of application notes if you fossic around...

05-04-2006, 03:57 PM
dunno yet...haven't built the toy.......just collecting stuff together....considered an air motor like for model airplanes...but I'm afraid of leaking seals at a bad time...just think the spring motor would be more reliable.....to test the idea I used a cheap sears electric screwdriver....

Mike Vogdes
05-04-2006, 06:34 PM
How bout an air driven socket wrench with an inline valve to control your preasure so as to make it variable speed?

05-04-2006, 08:22 PM
needs air...I ain't got no air....

05-06-2006, 05:47 PM
The best that I can suggest is an Andersen window sash balancer. They wind two strong cords onto drums with a flat spring. The large ones pull about fifteen pounds for about three feet.