Quick and Dirty Dividing Head

Hawkeye

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Okay, you asked for it. I made up this little dividing head / rotary table for my mini-mill. I know I said I'd take it apart to photograph it, but I seem to recall that I trued up each stage as I mounted it on the hub. I don't want to risk throwing out the setup by taking it apart.

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Ignore the tilt table and start with the long base plate bolted to the table. Next up is a bushing plate with a hole closely sized to fit the hub. The main feature is a 36- tooth sprocket mounted on a hub held down by a center bolt recessed into the base plate. The two towers at the ends have steps milled in for a rub fit to the underside of the sprocket.
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The tops of the towers are grooved for an easy slide fit on the two index blocks. The thinned down area at the tip of the block is to allow it to clamp the sprocket to the step on the tower while still fitting under a faceplate which can be bolted to the top of the sprocket. The holes around the hub and the raised portion are sized to hold chucks and plates used on the standard HF style of mini-mill.
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The key to indexing twice as many angles as the sprocket has teeth is seen on the underside of the index blocks. The slot in the tip brackets a sprocket tooth (giving angles on the ten* points) while the angled outside faces wedge into the space between teeth (giving the 5* spaces).
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The table turns easily by hand when the two index blocks are pulled back. When it reaches the right location, the blocks are slid forward and the setscrews tightened to lock the table in place for drilling or milling.
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Actual details are up to the individual builder. The concept of using an inexpensive, readily available sprocket (or gear) as an indexing source is the main point of this post.

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That is ingenius! :)

Gives me a few ideas I might try out some time in the future when I get my shop sorted out.

Thanks for sharing Hawkeye ;0
 
Thanks a lot for posting those pictures and the explanation. It's very ingenious and effective. +#$


José
 
It maybe quick and dirty to your self but I'm sure most out the like the above and myself see this as well planned and executed. Especially love the idea of using the 36t sprocket, Instant 72 index points. With another set or two of locks with the points at different profile would quickly double that to 2.3deg increments (if you wanted/needed it)
 
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For those that don't go to the Horology child board. you might like this Q&D indexing plate made for any one interested in making the 8 day clock and has not got a dividing head.
A ring of holes for each gear a complete set on one plate.

Not as strong as Hawkeys but we are only cutting small brass gears

100% for lateral thinking Hawkeye.

BRIAN.

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Brian, I like that. Simple, but not easy. Lots of time involved to be set for a long time.
 
I absolutely love that solution Hawkeye. It's got me thinking of how I would go about building my own.

Thanks for sharing,

-Ron
 
The best part is how it engages both the points and the gaps, that's true genius. I would have found a way to engage one or the other, and never even thought that it could be better. Even if I did, I'm sure the mechanism would have thirty-two movinh parts and be so complex that I'd never make it work 100% of thd time!

Thanks for sharing!
 
Sometimes you just have to think outside the box. Great job , it would work well for most of the hobby machinist and be in our price range for sure ,at least mine. Thanks again.
 
Very nice !!
Great Idea for someone needing an indexer but can't afford one. I especially like the way it's mounted on the angle plate. Can be used at any angle.
 
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