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rbertalotto
12-25-2014, 03:50 PM
Quick questions.....

With a 1-1 gear drive system, 12V DC motor, with PWM control, for speed and Forward/Reverse, driving the right hand side of the shaft that drives the cross slide......

What should I be looking for in the way of torque and RPM?

I'm going to use two 40 tooth gears so I can easily disengage when I want to use the lathe manually.

I'm using a JET 12-36 BD. This lathe has a separate screw for threading and a separate shaft to rotate the apron handwheel. A lever can engage either shaft. The entire gearbox can be disengaged so the leadscrew is not attached to anything but the cross slide.

Just need a motor and controller.

Thanks

Joe_B
12-25-2014, 04:55 PM
The required torque depends on a lot of things like how tight the gibs are and how heavy a cut you are taking to mention just a few. You should measure it using a lever and a weight and then scale up the torque based on that measurement.

Check out polulu for motor controllers.

Gary Paine
12-25-2014, 05:08 PM
Quick questions.....

With a 1-1 gear drive system, 12V DC motor, with PWM control, for speed and Forward/Reverse, driving the right hand side of the shaft that drives the cross slide......

What should I be looking for in the way of torque and RPM?

I'm going to use two 40 tooth gears so I can easily disengage when I want to use the lathe manually.

Thanks

When I am cutting with the cross slide, I'd be surprised if I wasn't rotating the hand wheel more than one rev per minute. Try it and estimate minimum and maximum to set your speed range. Then choose your gears so the motor is geared down and running at full RPM with your output speed at the maximum you want. Doing that will assure that you are able to use all the power your motor can deliver. Torque is multiplied through the same gears that are reducing the RPM.

Evan
12-25-2014, 08:33 PM
I use a Gilmer drive belt (toothed belt)+ a right angle worm gear drive motor. That gives plenty of torque and if something jams the belt just skips.

Full info including controller plans on my site here: http://ixian.ca/gallery/

rbertalotto
12-25-2014, 09:19 PM
I just ordered the following parts from Amazon to power my lead screw on my JET 12-36BD

RioRand Upgraded RRCCM6NSPC 150W 6V 12V 24V Reversing Switch Adjustable DC Motor Speed Controller PWM

12v 6a Adapter Power Supply for LCD Monitor with Power Cord

Reversible Electric Gear Motor 12v 50 RPM or 35RPM Gearmotor DC 12VDC

Total order cam to less than $80 including shipping.

Should be fun!

rbertalotto
12-25-2014, 09:25 PM
EvaN...Simply amazing lathe you built. Fantastic workmanship. I enjoyed the pictures on your site..Thanks!