Sorry about lack of clarity: referring specifically to a "Precision Universal Tool Head" (boring head) by the Precision Tool Co/Brooklyn, NY. IOW, Universal "brand"
Ray- That is what I was afeared of: removing the collar might only reveal more gubbins....
Ken,I did not realize there was also a "Universal Engineering" Company boring head that is slightly different. Lower profile, not fully universal. Might yours be one of that brand? If indeed yours is a Brooklyn made unit, it would be great to hear the correct procedure to remove the shank.
On account of shanks are damn hard (Rc); and in fact it is easier for me to set up on grinder than for carbide on my small lathes. The swivel table alone on the grinder is easier and more accurate to set for making machine tapers. Though come down to it, i might rough on lathe. A universal (type) boring head can be advanced or retracted in any increment by operator input (usually a crank) while it is running. You can lower it to a given height in a bore, crank until the tool cuts (say) an O-ring land a given depth, and then retract the tool, all while it is running. This is under precise dial control, not gripping a friction ring. Contrary to your comments, on a Universal (type and brand) the shank needs to be perfectly centered so the stationary center ring is not doing the hula while the operator is trying to crank the spindle to advance it in or out while it is running. Being a facing head, it also requires to be dead square to the axis of rotation to get flat facing.
Thanks for the input, Ray and JR: The MT4 has enough meat to just make an R8 taper, which would vastly increase the resale value. My SB mill has a NMBT30 taper which would be the most convenient machine for me to use it on. Maybe 1" straight should be the default.
Problem being the extension of holding it in an ER40 collet chuck, adding almost 3" to the stack height down from the spindle face.
I'll probably end up doing #30 taper, but if the shank was easily removable, I'd feel better about just making a replacement shank & turning the MT4 into R8 for "if I ever sell it".
Here's the type I have, Universal Tool Company:
Precision Universal Boring Head Boring Bar Milling Tool w Holder Set MT4 | eBay
Here's a Universal Engineering:
Universal Engineering NMTB 5 with 4 5 8" Boring Head STK 4324 | eBay
smt