Rotary Table Chuck And Adapter Plate

My new ebay special, made in China (I'll never learn. LOL) , 8" 3 jaw chuck and adapter plate arrived today. I got it mounted on the 10" rotary table I picked up (used) this summer. Now to build a tail stock.

That looks perfect. I think if there's any place a Chi-com chuck is going to suffice, a rotab is it. As long as it squeezes the part right!

I have a couple of my extra chucks mounted to square plates. That way they can be bolted to the rotab or simply clamped in the mill vise for holding round stock.

This is what happened when I got a RT

Chuck centers on plug centered on 8" vertex RT mt3 center,3/8" dowell in it , 3 jaw dose same thing.
the fixture plate 1 1/4" mic-6 I think ,holes are for other things

I've had a few requests for muzzle brakes and flash hiders. I had this little tilting 4" table with a 3" chuck. It did work, but I had to take things so slow to avoid chatter or completely knocking the work loose. Stronger, bigger, heavier iron was the answer. Turning the key is a little stiff, but I haven't cleaned or lubed it yet. I don't see why this won't serve the purpose just fine. Will I be building Pratt & Witney rocket engine parts with it ? No. Will it get me within a couple of thou if I take my time setting everything up just right, and keep it there while I do my cuts ? No doubt. The chuck and adapter plate are $240 USD shipped within the US. All said and done, including import fees, a little more shipping (I suspect), currency exchange...the usual stuff they saddle us poor Canadian guys with....LOL.... all said and done, it was $341.07 Canadian pesos, delivered to my door step. Still cheaper than any 8" chuck that I can buy here by half.

I went with a chuck already mounted on a MT2 adapter from KMS... Since my table is 6" and the chuck I wanted was 4", it was very inexpensive - under $160 That said, I have to take light cuts (which is what I am inclined to do anyway...)

like idea of mounting chuck on square plates

Some nice ideas here. I'm just figuring out an adapter plate for a 5" chuck on a 6" RT with 4 slots. The chuck is a plain back with 4 M8 threaded holes in the rear, as opposed to front mount pass-through bolts from the front of chuck. Front mount bolts would have been dandy & negated need for plate by bolting chuck directly into RT tee-slots, but its not available in this particular chuck size. Anyway, got me thinking about a few aspects of the plate:

- I had not contemplated machining a male boss on the adapter plate to engage the chuck's rear female recess like you would normally see on a lathe adapter plate. I'm not clear if these posted examples have it? My understanding is the boss is required on a lathe to prevent the chuck from moving off axis with cutting forces. There could be similar lateral cutting forces on the RT from side milling, but hopefully not as much as lathe turning. OTOH, maybe interrupted (milling) cuts might be worse? This got me thinking about the upright mode with RT on its side with table & chuck axis pointing horizontal. Now the weight of the chuck would want to slide it downward. Plus any down cutting force like drilling would push it similar to lathe example. Without a boss, I guess you are relying on friction of the 4 M8 bolts. Thoughts?

- My plan was to be able to use this same plate on the mill. Unbolt from RT and use any 2 opposing bolts on the plate to mount to a common mill Tee, or I guess 2 different Tees at some orientation. Its not appreciably different than 2 clamp bolts holding a vise, at least for light duty milling. Any thoughts?

If you are going to use it on the mill, it might be handy to make a square boss that bolts to the adapter plate so you can hold it in the vise... Down the road, of course...

It's nice to see people bouncing ideas around! Great stuff.