Drive motor for rotary welding table

I love Dave Smith's simple, elegant solutions. And yet if I can find an excuse to make something more complicated - I guess I've got the Rube Goldberg gene - I can't resist; after all, we're on the Hobby-machinist website, right? So I'm a fan of treadmill motors, cheap, reversible, easy speed control, use a footswitch (or two if you want to reverse without taking your hands from the tools). $50 used motor, $15 router speed control from HF (or heater control even better - slower minimum speed), $5 full-wave rectifier and $10 footswitch and $? lazy Susan from Amazon, and voila!
Two comments on other ideas: First, I've tried wiper motors and security camera motorized mounts set to scan back and forth to turn a wash pot full of solvent back and forth, and it was really too much for either to handle continuously, plus the wiper was a little jerky at the end of travel. I don't think the wiper sweep comes close to a sine function, more militaristic as in "hurry up and wait". Second, potentiometers alone often don't work out because you need pretty high current ones, $$ and hard to find; don't work with most AC motors and DC motors have low torque with them. (Motor speed controllers use very low power potentiometers in a circuit that pulses the current at a high enough value that it maintains torque even at low speeds.)
 
I picked up a pwm dc motor control for 20 bucks to try with a big 24v wiper motor i have already. If it doesnt work i will worry about it then. Its foing to have to wait now as i have too much work lined up. Plus i just spent a fortune on some fabrication equipment:):chunky::grin big::grin:
 
I added a power drive to a manual bead roller a couple of years ago. I used a harbor freight drill motor attached to a 14:1 gear reduction box that was coupled to the bead roller with a 5:1 reduction chain/ sprocket setup. It is reversible simply by reversing the drill... and I powered it through a cheap foot pedal that I bought off ebay, so I can control the rotation with my foot while guiding the sheet through the roller with both hands.

Something like that may work for you and is not expensive....

-Bear
 
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