Rotary table chuck mounting

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Dale Grice
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Rotary table chuck mounting

Post by Dale Grice »

I have come to the point where I need to make the dive into mounting a chuck on my 10" rotary table. And I am getting mixed thoughts on how to proceed. My table has a Morse taper in the center.

I have a lathe with a D1-3 spindle and a 3 jaw, 4 jaw and face plate. Would be nice to just use those to mount using a scheme such as this: ... p?th=90112

Then there is the option of maybe getting a 8" 6 jaw 2 piece jaw set tru plain back chuck. And getting a d1-6 adapter to use in the lathe as well. But moving that with a part in it from the lathe to the rotary may not have a center reference like a D1-3 nose. I do not know if the back plates on these plain backs have an index ring. Any info? And buying the above referenced chuck looks quite expensive. Searching ebay, craigslist, and here yields one or two possible flat back chucks. Buck chucks do not seem to have and adapter plate for an 8" chuck to D1-3 mount. So, is 8" going to be too big?

I'd rather not take time off my current need to make the D1-3 adapter referenced in the link above.

Anyway, thoughts or suggestions to add to my confusion?

Dale Grice

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Re: Rotary table chuck mounting

Post by arborist »

I do not understand the reference to a D1-6 adaptor. Is that a typo.?

A full depth body 8" three jaw scroll chuck plus backplate is a little big for D1-3. A slim body, integral mount 4 jaw chuck in that diameter is OK.

It is not clear what you want. Do you need to move things between lathe and mill? Do you simply want an economic workholding solution for the rotary table?

An option would be a simple setup on the mill and then use a chuck-within-a-chuck on the lathe (see Chris Maj Youtube as well as Edge Precision).

An alternative to making a D1-3 nose is to find a scrap machine with a D1-3 spindle, pull the spindle and cut it down.

You can utilise the Morse taper in the RT to help you align a chuck. Buy a Morse taper test bar (also known as lathe alignment bar). Poke it it the RT's taper and then clamp your chosen chuck onto the parallel portion of the test bar. Secure the chuck to the RT. Standard top clamps can be used or if you need to clamp below the front (top) face of the chuck, use toe clamps in a slot in the chuck or pin clamps in a hole (see Fig. 8.21 here: ... rap-clamps). Release the chuck. Remove the test bar.

The advantage of pin clamps is that you can use the holes in the chuck backplate for indexing/ dividing when it is back on the lathe.
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Bill Shields
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Re: Rotary table chuck mounting

Post by Bill Shields »

I bought a cheapie chuck with removable backplate.

From a flat piece of metal about 3/8 thick, I made a disc that mates with the pilot on the back of the chuck and has an id bore that agrees with the rotary table. This allows the disc to be centered on the rotary table.

Metal disc bolts to rotary table, chuck to the disc with appropriate hardware.
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Re: Rotary table chuck mounting

Post by GlennW »

I don't know what you have for a milling machine, but by the time you stack all of that stuff up, (rotary table, camlock adapter, and chuck) by the time you put a part in the chuck you won't have any room left under the mill spindle for much other than an end mill in a collet. Not much chance of a drill chuck and drill.

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Re: Rotary table chuck mounting

Post by RSG »

Here's my solution!

A chuck body mounted to a 1/2" steel disk with slots, then a ring. I found using the morse taper for chuck alignment still not accurate enough so I added a ring with four 1/4-20 bolts for micro alignment. Works awesome. The nice thing is with that chuck is a I have three of them so the chuck body stays on the rotab and only the jaws (soft jaws and base jaws move from lathe to mill.

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Re: Rotary table chuck mounting

Post by liveaboard »

I made an adaptor to mimic my threaded lathe spindle, so I can use all my lathe chucks.
I started by cutting a small indexing groove into the rotary table top plate, and a matching insert ring.
I spaced the bolt holes so that the adaptor can also bolt directly into the table slots.
The assembly is pretty high. Centering is good but I'm ashamed to admit it has a tiny little wobble in it.
rotary table adaptor 1.jpg
rotary table adaptor 1.jpg (83.41 KiB) Viewed 527 times
rotary table adaptor3.jpg
rotary table adaptor3.jpg (125.59 KiB) Viewed 527 times
rotary table adaptor4.jpg
rotary table adaptor4.jpg (118.73 KiB) Viewed 527 times
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