Making A Boring Bar

I realized this morning I need to get this done or Christmas would consume all my shop time.
I first rough cut it on the bandsaw and belt grinder. I mounted the bar in the mill with the vise at a 45 deg angle and cut the pocket all the way across. Then I changed out the 3/8" end mill for a drill and drilled the hole for the screw in the middle of that tool path. That way I know the distance from the back wall of the pocket is perfect.

31707715821_01035fb60f_h.jpg

31014565173_aed805d90d_h.jpg

Works great on test cuts!

30983544204_8dcccb3b76_h.jpg

Question: If my insert is a tCmt (C=7 deg relief angle) what is the minimum diameter I can turn with this? Should I get a tPmt or will the .750" bar drag first?
Robert
 
Last edited:
Back
Top