How do you attach a 3-jaw chuck to a mill's table?

news:6c4001e0-9ad8-4f2d-a69f- I use lathe chucks on a rotary table, table has a large hole in the center extending past the T-slots. I just made a replica spindle
nose, slotted the bottom for a bar that fits the T-slot and use a bolt through the center of the spindle nose clone to clamp the bar to the table. I can spin any chuck I want onto the table, with or without workpiece from lathe operations. Stan =================I have a BS-0 dividing head that doesn't yet have a chuck fitted:
http://www.taiwantrade.com.tw/resources/member/94764/productcatalog/fe561200-0e5a-4f1f-b48a-b826b7c4d13d_67_201100004996_L.jpg
The spindle thread is 1-1/2 - 8.
How careful do you have to be of the cutting force direction to keep the chuck from unscrewing?
jsw
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On Thu, 11 Oct 2012 17:40:00 -0400, "Jim Wilkins"

In my experience Jim I have found that if the chuck is spun on smartly it will be tight enough to stay threaded on when milling. When milling on the OD of a part in the chuck the cutting forces will tend to unscrew the chuck but it has not happened to me. And I've used screw on chucks a lot when milling parts using the dividing head. In fact, the problem I have is getting the chuck back off if I screw it on too smartly. When I machine adapters to use chucks with threads I do all the work in one chucking so that the shoulder that the chuck tightens against is square with a line through the pitch diameter. This helps greatly keeping the chuck on. Eric
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wrote in message

Usually I drill and tap for a setscrew in the hub area of the back plate, a short piece of brass rod placed underneath the setscrew will keep it from galling the spindle threads.
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I've done that to fix the dials on an Enco milling machine. The separate plug didn't work so well for things that come apart. Even if I don't lose it, it doesn't go back in the same way.
I had better results with a piece of hard solder under the setscrew, which squishes out and locks itself into the threads so it stays in place, but it doesn't completely release and the assembly is somewhat difficult to unscrew.
jsw
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On Thu, 11 Oct 2012 17:40:00 -0400, "Jim Wilkins"

Pretty careful. Tighten it up too loosely..and it will start to spin. Tighten it up too much and it gets to be a pain in the ass to get it off.
Now..if if you can find a 4degree Camlock chuck..thats very easy to set up. Which is what Ive done. So I can use the chucks from the Hardinge lathe on the mill. But then..I do have a half dozen 5C vises..that hold a 5 C collet and allow you to put in the work and open and close it with a lever.
This works Great for stuff under 1 1/16" inch or with expanded 5cs for some bigger flat stuff
http://www.ebay.com/itm/5C-ANGLE-COLLET-FIXTURE-HORIZONTAL-VERTICAL-MILLING-NEW-/260366999475
http://www.ebay.com/itm/5C-HEAVY-DUTY-COLLET-FIXTURE-VERTICAL-HORIZONTAL-MILL-/350462906533
etc etc. That stuff goes for very very little money if one finds it used. http://www.ebay.com/itm/PHASE-2-ll-TWO-5c-COLLET-FIXTURE-/170922840326
Hell..Ill bet Iggy has a number of them already, he could sell cheaply.
Then too...if anyone can live with 5" of height...one can use one of these to hold a chuck..the necks are threaded
http://www.ebay.com/itm/Horizontal-Vertical-5C-Collet-Index-Fixture-new-/310357238089
See the black ring at the left end of the fixture..where the collet goes? That spins off and it will screw into many chuck backs.. I cant remember the thread pitch..shrug
Gunner
Gunner
"The best government is a benevolent tyranny tempered by an occasional assassination." --Voltaire
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On 10/11/2012 12:02 PM, Paul C. Schiller wrote: >

Au contraire mon ami---clever, bright, intelligent people get the answer to a problem the easiest way possible.
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On Tue, 9 Oct 2012 09:40:31 -0700 (PDT), "Paul C. Schiller"

Mount it to a bit of steel..then mount the backing plate to the t slots
this assumes that you are mounting it face up....
Gunner
"The best government is a benevolent tyranny tempered by an occasional assassination." --Voltaire
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