Yea that's the one Tony! I guess we'll see what happens!You mean this, right? https://www.pennstateind.com/store/PKMBCM2.html
I have not used this, but it seems popular. When available, I prefer the TBC bushings with the 60 degree centers - just a personal preference. The 60 degree centers (dead and live centers) will also work with the non-TBC bushings (bushings with the hole in the middle).
Well this is called a Turn Between Centers mandrel. I'm not sure how this will flex when the mandrel ends are only about 1 1/2" long.TBC and a mandrel are two different things.
When using TBC, there is no mandrel used.
Mandrel's will flex almost always. That will create off-center barrels.
I admire your enthusiasm, but this thing only cost me $30. Lol If it don't work, then I'll look to using or making something else. My mandrel still works great but thought I'd change up a little. I appreciate all the info. It may be a project for one day. Thanks dogcatcher!!You can make one of these out of 3/4" piece of round aluminum. Take a 4" length of 3/4 round stock aluminum, using your collet chuck drill through the center with a drill bit that is the same diameter as the pen mandrel.
Then cut the 4 inch long piece in to a 3 and 1 pieces. Drill and tap from the top a hole in both for 1/4-20 set screw. Cut a 3.5" piece on an old mandrel and mount it in the 3" piece. Then cut a 1.5 inch piece of mandrel and mount it in the short piece of aluminum. Put the short piece in your collet chuck and ream a 60 degree center using a started bit.
To use, the long piece goes in a collet chuck, this is your driver, add appropriate bushing, the short piece is a little trickier to handle, place blank up against the driver, and the short piece along with bushing and slide up the tailstock with your live center.
The small piece of the mandrel i=is there only to hold the bushing, and inmy opinion it is TBC.
This method works real good with pepper mills, duck calls, all wood deer grunts etc. Just need to create a stub of the correct diameter on bothe ends of the driver plug and the live center plug.