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View Full Version : How much torque would it take?



Michael Weber
01-27-2015, 12:50 PM
I'm playing around with putting a geared reversible electric motor (AC or DC) on my old Woodpecker router lift. Looks like a pretty easy fit if I can find the right motor. Anyone have any kind of idea what amount of torque in foot pounds or other rating (kg per centimeter, etc.) it would take to operate the such a lift? It turns pretty easy with the crank that comes with it but I have no idea how to convert that into a motor rating. Thanks

Jason Roehl
01-27-2015, 12:59 PM
You could measure it with an inexpensive beam-style torque wrench.

http://www.amazon.com/Neiko-Classic-Needle-Style-8-Inch-2-Inch/dp/B0019VMI0Y/ref=sr_1_1?ie=UTF8&qid=1422381347&sr=8-1&keywords=beam+style+torque+wrench

I suspect you'll be in the general vicinity of 50 in-lbs or so. Sounds like a job for a low-speed DC motor, like a cheap cordless drill...

Marty Gulseth
01-27-2015, 7:05 PM
Please keep my comments in context - I've had my Woodpeckers Sidewinder installed in my table and played with it for all of part of three days...

That said - I don't think that the big issue will be torque. I think that, instead, you will find that having your motor turn slowly enough to achieve the fine adjustment that you want will be the bigger challenge. I say this based on experience with some other "remote control" systems I have used...

Best wishes!

Regards, Marty

glenn bradley
01-27-2015, 8:09 PM
I have used a PRL for years and agree with Marty; the fine tuning will still need to be done by hand. I use a drill motor with a hex drive/u-joint to move mine into the 'near position' and then finalize by hand. You could do the same with a motor as you describe as long as it would allow "free wheeling" once power is disengaged. As to torque, I used to use this little Costco $14 screwdriver to move the lift and it did so effortlessly so the torque is pretty low.

305286

I just use the Ridgid drill motor now since it is used for the router table AND as an additional driver for the shop whereas the Costco driver was pretty worthless for anything else.

Steve Baumgartner
01-27-2015, 9:45 PM
Just to reinforce, if you gear down low enough that you can make small rotations with the motor, you will find that torque is not an issue!

John Gomes
01-27-2015, 10:02 PM
I prefer the drill/hand method, but a rotisserie motor might be slow enough and pack plenty of low geared torque.

Bob Michaels
01-27-2015, 10:22 PM
I agree with the others that the fine adjust will be the issue. I just went through the gear motor decision with Grainger's tech people for motorizing my Delta drill press table. Wound up using a Dewalt 20 volt compact drill and it works just great but a drill press table doesn't need fine adjustment. Had to use setting 9 or greater on the drill to avoid clutch slippage. On the other hand I have a new Jessem router table with the side-mounted hand wheel and that gives me all the effortless rough and fine adjustment I could ask for. Really a nice, but expensive, solution.

Jim Barstow
01-28-2015, 12:39 AM
Can't provide specifics but I've started research on CNC systems. Stepper motors are available with lots of torque and with very fine positioning. You'd have to build some electronics and software to control it but it wouldn't be too difficult. With an Arduino and a stepper controller you could build a fully digital control.

Michael Weber
01-28-2015, 12:18 PM
Thanks for all the input from everyone. It was all very helpful. Jim, I actually started looking at the torque ratings of steppers and the Arduino system after getting the first reply's. Although I have played around with steppers a little bit (using LabView) before I retired I don't know a lot about them. Do you know if it is possible to just feed a pulse to the proper directional winding of a stepper (from some kind of pulse generator) to cause it to operate? That way, instead of an automated control system a simple double pole switch could raise and lower the router?