micro-controller based dividing head

[EclecticNeophyte]

Here's my latest homemade tool...just finished the wiring and testing today. It's a dividing head, using a NEMA 23 stepper motor, coupled to a ER20 collet chuck via timing pulleys and belt. The ER20 is mounted in a couple of sealed ball bearings, that are in turn pressed into a 3" x 3" x 5" block of aluminum. The stepper is capable of 400 steps (0.9 deg/step), with a 4:1 ratio on the timing pulleys. This results in a maximum resolution of 1600 divisions...




I plan to use this dividing head, to cut spur gears and timing pulleys for other projects.

-EN

[Paul Jones]

EN,

Nice design and something I could definitely use. Can you describe the electronic circuits or point us to a website with the info? Does the LCD panel display a self-contained interactive dialog or is the setup for number of divisions all done via a computer interface? I am interested in building something similar.
Thanks, Paul

[EclecticNeophyte]

Hi Paul,

Interaction is completely via the LCD display and buttons (i.e., the SainSmart LCD Keyboard interface). The display mounts 'piggy-back' onto an Arduino UNO, and uses firmware written (I think) by Chuck Fellows. This unit mimics one produced by Chuck, which is described more fully here: (Electronic Dividing Head using the Arduino - Home Model Engine Machinist). You can find a lot of info on the web just by searching for terms like "electronic dividing head", or "stepper motor dividing head", etc..

From that you will see that the idea isn't unique to Chuck, as there are others who have done this as well. Some start with an old surplus mechanical dividing head, and simply fit a stepper motor to it, along with some sort of controller and brains...

In my case, I didn't possess a dividing head, but had previously built an indexing head with crude hand made indexing wheels. The accuracy just wasn't there... so when I found this solution, the decision to build one was simple. I have a number of small micro controllers from past projects, and was able to slap this thing together once the mechanical aspects were made. I'll likely gravitate away from the arduino, and to something like the MSP430 by TI as time allows...

Good luck, and let us see what you've built!
-EN

p.s., one other modification I'll be making to this EDH, is to shorten the motor mounting plate; which will bring the stepper closer to the spindle. That will reduce chances of interference with parts of the mill.

[kbalch]

Thanks EclecticNeophyte! I've added your Electronic Dividing Head to our Machining and Measuring and Marking categories, as well as to your builder page: EclecticNeophyte's Homemade Tools. Your receipt:

Electronic Dividing Head by EclecticNeophyte

tags: Arduino, divider, electronics

[Paul Jones]

EN,
Thanks for the references and info. This is very helpful. I too like looking through Home Model Engine Machinist for ideas and have published a few articles there. I am also starting to follow John Saunders (aka NYC CNC) on YouTube for his future project about a 3D engraver using stepper motors controlled via Arduino and programmer using common G-codes.
Regards, Paul Jones

[Wildon]

EN,great project,I think the ratio you're using should put it on the money for layout work! Good craftsmanship .

[DIYer]

This is new to me, an electronic dividing head. Great handiwork!

[EclecticNeophyte]

Thanks EclecticNeophyte! I've added your Electronic Dividing Head...<snip>

Thanks Ken! And thanks everyone for the kind words!

-EN

[Harris Creek Central]

I started with this project some time ago, but never really got it running . I must get back to this soon. I have all the arduino and I have worked with Chuck trying to see where I went astray. This has just given me the kick I needed to try again.

[Saltfever]

I realize the OP is more than 5 years old but for some reason Jon has just recycled this very interesting thread.

EN: if you are still around can you give us an update on the dividing head. Did you ever convert to the TI MSP430? And why do you consider that a better choice that the Arduino?