I wanted an ER-32 collet chuck for my Atlas 6in lathe. I have one for my sherline lathe from Mr. Beal and love it. But to use it on my Atlas I had to stick an MT2-3/4-16 adapter in it and that cut down on feeding rod through the spindle. I have the later edition of the lathe and they changed the spindle thread from 1-8 tpi to 1-10 tpi. Now I can find er32 collet chucks all over the place for 1-8 but in order to use one on my lathe I would have to make or buy an adapter or recut the threads on the one I have for the Sherline. None of which I wanted to do. I bought one off ebay I thought I could turn down and re thread to fit but I ruined 4 or 5 of Mike Roux's carbide inserts trying the thing was so hard.
I belong to a taig owners club forum that has a member that really really know his stuff. He has a tutorial on how to build a collet chuck and its link is here.
Atlas 618 ER Collet Chuck
I pretty much followed his tutorial step by step with the exception I cut the collet taper before I cut the threads. I also had the Beal collet I could mount and match the angle with my compound which took all the guess work out of it.
I had to make an mt2 adapter that would pass through the inside of the collet chuck and into the spindle so I could grip the spindle to manually turn it to make the threads. Here's a picture of the collet chuck I made. I knurled the back end to aid in gripping it. THe nut is from the one I couldnt get turned down and ruined. I did order the 12l14 steel to make it off ebay.
After cutting the inside taper I did run the dial indicator on the taper and it had .0015 run out. When I finished the threads for the nut I put a piece of .375 brass in the collet and made some sample cuts and put the D/I back on it to check run out on the actual cut. It measures less than .001run out. It does come off zero but only about 1/2 way to the first mark. If i need to test it any closer I will have to get a dial indicator that can measure smaller than .001. In reality im calling this one good enough for pen parts.
Take the time to browse around in Dean's site he is a very talented man.
I belong to a taig owners club forum that has a member that really really know his stuff. He has a tutorial on how to build a collet chuck and its link is here.
Atlas 618 ER Collet Chuck
I pretty much followed his tutorial step by step with the exception I cut the collet taper before I cut the threads. I also had the Beal collet I could mount and match the angle with my compound which took all the guess work out of it.
I had to make an mt2 adapter that would pass through the inside of the collet chuck and into the spindle so I could grip the spindle to manually turn it to make the threads. Here's a picture of the collet chuck I made. I knurled the back end to aid in gripping it. THe nut is from the one I couldnt get turned down and ruined. I did order the 12l14 steel to make it off ebay.
After cutting the inside taper I did run the dial indicator on the taper and it had .0015 run out. When I finished the threads for the nut I put a piece of .375 brass in the collet and made some sample cuts and put the D/I back on it to check run out on the actual cut. It measures less than .001run out. It does come off zero but only about 1/2 way to the first mark. If i need to test it any closer I will have to get a dial indicator that can measure smaller than .001. In reality im calling this one good enough for pen parts.
Take the time to browse around in Dean's site he is a very talented man.
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