YADH - Yet Another Dividing Head

[EclecticNeophyte]

Hi Neophyte:

I read your article about your Dividing Head adaptation and it so happens that I'm planning a similar conversion using a 10" Rotary Table. To that effect, I decided (empirically) to go for a NEMA 23 Stepper Motor 200 steps, 24 V, 3A, 360 oz.in double shaft to allow attachment of a crank wheel at the other end. Since I don't have the capacity to program o assemble a driver and controller, I decided to go for a "stand alone" Programmable Driver/Controller sold by a guy by the name of Bryan Mumford in California.
It looks like a big calculator and can do all kinds of stuff including jogging and continual rotation plus makes built-in adjustments for "slack" or free play. By the way you obviously run into that situation, were you able to program your controller accordingly?
Also, what size and specs is your motor? If you wish you can write to me at scrdmgl@gmail.com

Regards from Toronto, Canada

Jorge

Hi Jorge,

Sorry for the delayed return...

The stepper motor I used, can be found here:

http://www.automationtechnologiesinc...at-282-oz-in-2

As the ad indicates, the torque is 282 oz in. As for the 'brains', I simply used what was laying around my shop at the time. I have a number of the Arduino UNO controllers, as well as a stepper motor (or three?) and the project evolved out of my collection of junk. One word of caution on spinning the stepper motor by hand, while still connected to the motor controller...Larger stepper motors make 'not too bad' permanent magnet alternators. Depending on how fragile the motor controller is, and how fast you spin the stepper it could fry the output of the motor controller. I learned this the hard way! This may not hold true of all of the motor controllers, but the one I was initially using couldn't tolerate the output pulses from the stepper motor.

Here's a link to a motor controller, similar to the one I ultimately used:

http://www.ebay.com/itm/CNC-Router-1...gAAMXQBg5RyW0Z


While I do have ~ 27 years experience as a software developer, I haven't bothered to modify the Arduino code to handle backlash, or slop in the gearing. Some day perhaps...

Hope this helps. I'll be looking forward to reading about your rotary table project!

-EN