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View Full Version : Dividing head purchase?



lotsa luck
12-06-2003, 12:51 AM
I find myself needing (wanting) a dividing head to assist me in my VERY custom construction of a remote control (very fast) shark fin. I have a lot of gears to construct. It seems that I have to buy real cheap or REAL expensive. Does anyone know of any middle ground ones with decent quality and capable of doing most divisions?
Thanks in advance!
Stay Safe!

SGW
12-06-2003, 09:38 AM
Depends on how accurate you need to be....

No personal experience buying a dividing head (I made mine, see Feb/Mar 2003 Machinist's Workshop), but if I were buying one I'd take a look at the imports in the Travers Tool catalog. My experiece has been that Travers tends to sell high-end and middle-to-low end, but they try not to sell junk. So, I think you'd likely do OK with one of their "quality imports."

Another route is a used machinery dealer (see "the usual suspects" who advertise in HSM, MW, etc.). A friend of mine got a very nice Ellis dividing head that way, for about the cost of a cheap import.

As far as doing most divisions: tabulate the divisions you need, and go from there. A commercial dividing head with the 3 more-or-less standard index plates can do a huge number of different divisions. See Feb 1991 Projects in Metal for a rather long-winded explanation of how to figure out that stuff. Or Machinery's Handbook can help you out. Briefly, to do N divisions, you need an index plate that will let you get the fraction M/N where M is the gear ratio of the dividing head. For example, to get 74 divisions on a dividing head with a 40:1 gear ratio, you need an index plate that will let you get the fraction 40/74, or 20/37, so you'll need an index plate with 37 holes (or some multiple of 37 holes) in it.

It is REALLY handy if you can get a dividing head that matches the spindle nose of your lathe, so you can interchange chucks/collets.


[This message has been edited by SGW (edited 12-06-2003).]

jim davies
12-08-2003, 01:36 AM
Just recieved a nice LW Chuck Co. dividing
head I bought on Ebay. They seem to be relatively common there, and prices seem good. Anyway, it was alot cheaper than any of the offshore stuff available new, and the size is perfect for a small knee mill.