I made an extended center drill holder
A center drill holder is a common enough project, usually using a scrapped taper drill bit or drill chuck adapter. The trouble with these is that my SB 10K only has 2" of quill travel and the typical holder just isn't long enough. So I read somewhere about an extended version and thought it would be a fun afternoon project.
The project started with a $5 JT33 to Morse Taper 2 Drill Chuck Arbor. The JT33 taper was cut-off at the bandsaw and then a MT3-MT2 sleeve was used to hold the work in the spindle. A hole was drilled and reamed for the shaft. That was removed and then the shaft was drilled and reamed 1/4" for a #3 center drill. The shaft was then turned down to fit inside the other part. The shaft was then removed from the lathe and a setscrew hole was drilled and tapped.
There was a beautiful sliding machinist fit between the shaft and MT2 taper part. Unfortunately, I wanted a press fit! :angry:
Red Loctite to the rescue! The silver-lining of this was that the taper was remounted in the headstock sleeve and using a dial gauge I was able to remove almost all the run-out by pressing on the shaft while the Loctite was setting-up.
You have to put a flat-spot on the center drill (I used a Dremel) so the setscrew will hold. Looks like it's gonna work pretty well.