# Jacobs Collet Chuck



## LJP (Nov 12, 2013)

This past weekend I spent both days in the shop and got a lot accomplished. 2 weeks ago I bought a Jacobs Spindle Nose Collet Chuck with a full set of collets (1/16" to 1-3/8" capacity) for $300. From what I have seen, this is a good price. I bought a 2-1/4"x 8tpi backplate from Jeff at Tools4cheap.
I started by trueing up the backplate, and drilling a 3/8" hole in the edge to help with removal from the spindle. Next, I used Ray's method of turning the shoulder .010" under a tight fit. 
I then needed to locate the three mounting holes on the back of the chuck, to drill clearance holes in the backplace. 
So, now I needed to use the 15" Troyke rotary table I had bought from CL 6 months ago and never used. Of course it needed some clean up first.
I used Tom's method of centering the rotary table, so I made a 2" diameter "bushing" with a .010" taper. Pressed in a 3/4" drill rod shaft. Bored the hole 1" deep, .749" diameter, put the shaft in the freezer for 15 minutes, heated the 2" bushing with a torch and pounded it home. It took 5 or 6 good whacks but it seated very nicely.
Now I could center the rotary table on the mill. I mounted the collet chuck with a 3/4" collet to locate the 3 backplate holes. 
Three hole bolt pattern, 120° apart, 4-1/8" diameter, piece of cake!
Took a piece of 3/4" mdf, and routed a recess to fit the shoulder and used double stick tape to hold it on the backplate. Mounted the backplate on the spindle, drilled a 3/4" hole in the mdf. Next used that hole to center the backplate on the already set up rotary table and drilled three 5/8" holes.
With everything put together, on the lathe. I dialed it in by tapping the collet, just like a 4 jaw. This was the easiest part! it only took 5 minutes or less to snug up the bolts, until tight with less than a half thou TIR. Very pleased!
So, I got the new collet chuck good to go, and dialed in. The rotary table cleaned up and a shaft made to center it on the mill. Very productive weekend! 
Thanks for looking, Larry


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## Tony Wells (Nov 12, 2013)

Nice job, Larry. And for $300, you did well.


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