[balsaman]

Here it is. I had a 20:1 worm gearbox and a Taig 3" chuck. Now I have a mini dividing head. You may notice there is no dividing wheel yet. You need a dividing head to make the first dividing wheel. I will make one with 20 holes for starters.

[HuFlungDung]

That's not funny, that's commendable. Good work, Balsaman

[Bloy2004]

Neat!
How much play is in that worm gear? I've been looking at reduction worm drives with hollow shaft passthrough to run an axel between two sides of a rack and pinion gantry. I haven't jumped in yet because of backlash issues so I was going to go the pully/belt reduction route to get the shaft to the desired rpm. Is that gear box able to adjust out the play?
John

[balsaman]

As an estimate it has about 1/2 a degree of play. It's not adjustable. I can probably modify it to make it adjustable if I find a job for it that requires more precision. Right now I just want it to make a variety of holes in a flywheel, that sort of thing.

Eric

[InventIt]

Sweet!
Now if you just remove the handle and bolt a stepper to it...

[BigDaddyG]

Balsaman,
Good Job! Now that the Worm Gear in not being used for constant turning, you may want to look into, either shimming one (or both) shafts up or down a few mm and that should take any backlash out of the gear mesh. As a production right angle drive, the gears are factory set to mesh concentric. Since it is now being used for indexing, you can reduce the backlash which will cause it to turn with a little more resistance but should solve any backlash problems. You would be doing what they recommend you not do in the field. As silly as this might sound, fill it with a very heavy oil (over fill) will also produce some added effect on the mesh as strange as it sounds, you would be in essence doing what they reccommend you not do in the field. There will be a Oil Breather Plug which you might have to replace with a regular plug.

Just a thought! Great job none the less! Let us know how it works for you.
Regards,
Glen

[HuFlungDung]

Rather than trying to eliminate backlash (which will never happen in actual fact), just learn to index in one direction like every other machinist has down through the ages

IMO, your effort would be better spent devising a brake directly on the main worm gear or a band brake around your chuck body. This will permit you to index and lock in position for some milling and drilling activity.

[balsaman]

It will some day have a stepper or servo on it.

I do plan to shim out the backlash AMAP.

Hu, I like your brake idea. I had thought I need to turn it just one way, but without the brake it could end up "wiggling" out of position. A lock or brake would prevent that.

Thanks for the ideas.

Eric

[balsaman]

Here is the first dividing head project. I tried to simulate a 2 piece flywheel. That is 20, 4-40 bolts in an 3" aluminum wheel. I am not sure what it looks like. perhaps the bolts should have been closer to the outside rim. Whatever, it still looks more interesting that a plain wheel.