Electronic Dividing Head using the Arduino

[Swifty]

Blogwitch, that's the kind of device that I need. I will look into it.

Paul.

 

[n7gtb]

Here's some pictures of the dividing head. I've hooked it up to the arduino and it works. More than enough torque and holding power using the NEMA 23 motor. The ratio of the timing pulleys is 12 : 60 or 1:5.

<photos snipped>

The spindle is an ER20 with a 3/4" shaft running in sealed ball bearings.

Chuck

Hi Chuck,

I purchased a similar ER20 spindle (collet chuck?) that measures 0.788" (+ or - a half thou), and am looking for sealed bearings...which ones did you use? I have a Timkin 204PP, but looks to be about 0.003" too small for the spindle shaft (or is this press-fit?)...

Thanks,
-Vern

 

[Swifty]

Vern, that would be a 20.00mm shaft, so you will have to use metric bearings.

Edit. I just checked the bearing that you specified, 204PP, that's a 20mm bore. The bearing won't be .003" small on the ID, the shaft should fit that bearing.

Paul.

 

[n7gtb]

Hi Paul,

The info I have for the P204PP is that the ID is 20mm...(OD is 47mm) Am I in error on this? Ref: http://www.timken.com/en-us/products/Documents/Timken-Ball-Bearings-Catalog.pdf (see p. 4)

Thanks,
-Vern

I just hit submit, and then noticed your edit... Thanks for the clarification. -Vern

...so converting my inches measurement back to metric, I get a spindle diameter of 20.0152mm... I don't know what tolerance should be for that item, but seems a bit large to me ... but then again, I'm also not used to working (or thinking) in metric.

Thanks,
-Vern

 

[n7gtb]

Vern, that would be a 20.00mm shaft, so you will have to use metric bearings.

Edit. I just checked the bearing that you specified, 204PP, that's a 20mm bore. The bearing won't be .003" small on the ID, the shaft should fit that bearing.

Paul.

Hi Paul,

The info I have for the P204PP is that the ID is 20mm...(OD is 47mm) Am I in error on this? Ref: http://www.timken.com/en-us/products/Documents/Timken-Ball-Bearings-Catalog.pdf (see p. 4)

Thanks,
-Vern

I just hit submit, and then noticed your edit... Thanks for the clarification. -Vern

 

[Swifty]

Don't know what's going on, I have an ER20 straight shank holder and it measures 19.99mm Dia. May be worn a bit as I have used it a lot.

Maybe you have one that's slightly oversize, might have to polish it down.

Paul.

 

[TorontoBuilder]

I've thought about making an electronic dividing head for cutting gears, but I have not the faintest idea what you people are talking about. Obviously electronics are not in my field.

Paul.

Haha I've felt the same way... I'm making really simple to follow plans for a control box.

The plans will include precise parts list, a clear diagram and pictures for the wiring of a perma-proto breadboard (or perhaps custom PCB board) to hold the power supply regulator & power output to the arduino board, cooling fan, stepper driver, and a few capacitors. I've spec'd a variable output step up/down regulator to allow the box to be tuned to match requirement of stepper motor selected. all anyone needs to adjust is a multi-meter.

I'm basically only waiting for my arduino Uno R3 and LCD/keyboard shield to arrive so I can get the final assembled depth dimensions in order to finalize the laser cut box design. It's a pain since I wanted button extensions and have completely enclosed unit.

Once done I'll upload it. That way anyone can make one regardless of knowledge of electronics.

I wonder if people would kindly post what torque motor they have been using, I can only find one affordable motor (~$50) thats 190 ounce/inch that's under the current limits of the driver chip. Otherwise its about double the price for a motor with greater torque under 2.2 amps per phase.

 

[Swifty]

I bought a book on basic arduino, started to read it, but it's still sitting where I left it months ago. Must get back to it soon.

Paul.

 

[goldstar31]

Moi aussi- which is not French for I am an Australian

 

[TorontoBuilder]

Moi aussi- which is not French for I am an Australian

me too... except there are so many great arduino instructions, videos and forums online it makes printed books superfluous. You just gave to dive in

 

[goldstar31]

I'm sitting with 4 pages of what seems gobbledegook with a little Arduino flashing. I'm supposed to have a sort of IQ which would get me into MENSA if I knew what it meant.

In another world, I ran- amongst other things a Technical Library for a whole operational RAF station- which is now the RAF Museum-----and I am struggling.

Somewhere on my Kindle is Mrs Beetons world famous cookery book- which says if you want a roast pheasant the first thing to do is catch the poor thing. All the rest of it, like killing it is next. Frankly, I'm lost.

On another forum, I was asking for a bit of no-how and people whom I know as exremely clever engineers- full time and hobby have advised me to--FORGET IT.

On that thought?


Norm

 

[TorontoBuilder]

Well Norm, if you want a dividing head out of your arduino wait till I post my plans and step by step guide.

I've attached one screen shot of the proto-breadboard version to see how easy the electronics can be to make permanent board.

I may even do a video.

 

[goldstar31]

Thank you but I've finally 'caught my pheasant' after N numbers of attempts and even a Proto-Pic book.

I've gathered a collection of Easy Drivers, Velleman VMA 03 things and a 3 NEMA23 HY200 2215 0150 AZ08 which have 8 windings.


The last do not identify( or seem to) with ANY other motors.

However, I must offer you my sincerest thanks and in the meantime Keep Looking East. That, I understand is where the last miracles came from-- and I missed them.

My Appreciation and Good Wishes

Norman

 

[ozzie46]

TorontoBuilder;

Thank you for taking this on. I'm eagerly awaiting the finished project. I too am wondering about the torque rating for the motor.

Ron

 

[n7gtb]

Don't know what's going on, I have an ER20 straight shank holder and it measures 19.99mm Dia. May be worn a bit as I have used it a lot.

Maybe you have one that's slightly oversize, might have to polish it down.

Paul.

After about an hour of working it down with 180 and 320 grit abrasive, the bearings now fit snugly. The local supplier didn't have the Timkens in stock (I only had one to begin with), but did have SKF equivalents, and at about half the cost. Part number ( if anyone is interested) is 6204 2RSJEM ...

-Vern

 

[harrzack]

Here is a link to yet another version of an Arduino based index head

I have a little different "user interface" - the way of entering the steps, degrees and such. I'd like to hear/see how yours performs under the mill... I'm haven't fully tested mine yet and am wondering if the steppers will give the needed accuracy for (light duty) gear cutting.

=Alan R.

 

[goldstar31]

Just an update to trying to get Arduino to load on my old Vista laptop.#

I've finally done it-after re-installing etc several times using Internet Explorer.

I changed to Firefox- and all simply loaded. For some reason, I now have Ports showing in the Control Panel.

More anon- I hope.

Meanwhile, my thanks to those who took time to assist me.

Cheers

Norman

 

[chucketn]

Here is a link to yet another version of an Arduino based index head

I have a little different "user interface" - the way of entering the steps, degrees and such. I'd like to hear/see how yours performs under the mill... I'm haven't fully tested mine yet and am wondering if the steppers will give the needed accuracy for (light duty) gear cutting.

=Alan R.

I have just ordered an Arduino Uno R3, Pololu Driver, 1602 LCD shield, and another kit to build a drive setup for my Vertex RT. Very interested in your version. Been looking at your website. Very nice...

Chuck

 

[RonGinger]

Alan, I like your interface using the rotary encoder, that is very well done.

You make some comments about the indexer working with a small step motor and that the heavy indexers of the past are not needed. You may need to test that a bit- your stepper motor must resist the cutting forces and I suspect they may be a god bit larger that you think. if youused a rotary table with a worm gear and drive the worm by a stepper then you can use a small motor because the worm will lock the table against rotation. You may have trouble with a simple belt drive to a shaft.

 

[goldstar31]

I've a Vertex BSO dividing head that can be tilted into a sort of dividing head. Yea, Ive a couple or three but the Vertex has some nicer features. I was cutting a 10" radius( for a Stent t&C) and boy oh, boy, did it move.

Food for thought, eh?

Cheers

Norman