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Prokop
08-10-2015, 01:47 PM
At the route 11 yard crawl I scored a small chuck, just the right size for my mill.

I plan to mount it to a plate to be able to mount it on the milling table. Anything specific to look for or anybody done it and can share a picture.

I am past the stage of exploring explored :)

Thanks!

Toolguy
08-10-2015, 02:20 PM
I have mounted 4 jaw scroll chucks on plates for milling, I use them fairly often. The plates have slots to bolt them to the table, but I usually just put them in the mill vise. I milled a circular depression in the plate for a light press fit of the chuck body, then bolted the chuck to the plate.

Paul Alciatore
08-10-2015, 03:11 PM
I have a four jaw (6") that I use on a rotary table (10"). I drilled three holes in the outer 1/2" of the main casting, at 120 degree spacing and I use three long cap screws with tee nuts to fasten it to the radial tee slots. Since it is a four jaw, precise centering is only done on the work it is holding. But most three jaw chucks do not have enough meat in that casting to use this technique: the screws would interfere with the scroll plate.

My Unimat, which can be used as a lathe or a milling machine, came with an adapter that screws into the chucks using the lathe's spindle threads and has a tee configuration on the other end which fits in the milling table tee slots. Mounting the chucks is simply a matter of screwing the adapter in the chuck and then sliding it into the tee slot and tightening it down on the adapter. This works well for the 3" chucks on that machine. But I rarely use it to mount the three or four chuck for milling. I always use the milling vise. I do use it for mounting a lathe faceplate on the cross slide for use as a drill press table. But, as I said, this is only a 3" chuck. I do not know if this would be strong enough for a larger chuck on a larger machine.

Frankly, I see no alternative to using some kind of plate.

I do not see any advantage in mounting a three jaw on a milling table. They are inaccurate as far as positioning the work. So you will always have a few thousandths of slop if you are doing identical parts so your zero position will have to be reacquired for each part. A vise with a vertical tee slot would be a better way of holding cylindrical parts for milling. It would be more repeatable on round parts and even the vertical positioning would be easier with spacers on the vise bed. Oh, and using the chuck key may be awkward.

If you are trying to initially set up for milling, I would think that even an inexpensive vise would be a better option.

wierdscience
08-10-2015, 03:28 PM
I have a four jaw scroll chuck that I bolted to a 1/2 thick 8x12" plate.It's offset to one end and there is a through hole bored through the plate the same size as the hole in the chuck.Normal operation with round stock I just stick a 3/4 dowel pin in the mill quill,clamp the chuck on it,dog the plate to the mill table and zero the DRO.

Square stock I have the chuck setup so the jaws are parallel to the long axis of the plate.That way I can just clamp it to the table using an 8" machinists square for alignment.

With the chuck offset on the long plate I can work the ends of long bars by hanging the chuck bore over the edge of the table and swinging the ram around to reach.

J.Ramsey
08-10-2015, 04:46 PM
I have a 6" mounted to a 1" thick Aluminum plate.

http://i1200.photobucket.com/albums/bb324/buellx1rider/3jawmill_zpsgenkihpn.jpg (http://s1200.photobucket.com/user/buellx1rider/media/3jawmill_zpsgenkihpn.jpg.html)


Have several hole patterns so I can hang over the edge of the table if needed for longer pieces like redrilling auto axle bolt patterns.
http://i1200.photobucket.com/albums/bb324/buellx1rider/3jawoverhang_zpsixnugiey.jpg (http://s1200.photobucket.com/user/buellx1rider/media/3jawoverhang_zpsixnugiey.jpg.html)

Doozer
08-10-2015, 05:27 PM
The overhang thing does look handy.
I have done that with a 5C collet closer also.

Mounting a chuck to the mill table can be as simple as
2 hold down clamps and threaded studs.
No need to complicate things, especially for one job.

-Doozer

boslab
08-10-2015, 06:04 PM
Looking at the chuck it sort of suggests a sine table sort of thing, sine chuck if you will, you could tilt the thing as required if you see what I mean
Nice job making it btw!
Mark

Prokop
08-11-2015, 06:41 AM
Thank you, gents, will put the shared info to good use.