Q1 - I have a set of Borite cobalt/Hss tools for my boring head. I managed to chip the cutting point (dropped it on vise). Figuring I didn't have much to lose, I slightly ground back the flat & the diameter relief angle just enough to restore a new cutting edge. That part looks good now, but just wondering - is there a big deal about the flat no longer being 1/2 the shank? (Maybe I'm getting mixed up with D-bits & such). Can I just compensate the slightly different tool angle (rake) relative to bore ID?
Q2 - now that I think about it, I always kind of tried to set these tools with neutral rake & had good results. But I'm not exactly sure where I got that from. Maybe positive rake can cut better but can deflect & cut larger diameter based on depth of cut or something? Negative rake... dunno!
Q3 - I've seen insert boring bars like pic for lathe toolpost boring, in fact I use some with CCMT inserts & more flat faced shanks, but still of round stock profile. I see some with totally round shanks too. Doing the price math, its actually cheaper to buy an insert type 0.500" shank boring bar & cut to length & use the variety of inserts I have. Is there any difference cutting action wise between how a boring head would hold the tool vs in a lathe? (Ie. both boring ID's).
Q2 - now that I think about it, I always kind of tried to set these tools with neutral rake & had good results. But I'm not exactly sure where I got that from. Maybe positive rake can cut better but can deflect & cut larger diameter based on depth of cut or something? Negative rake... dunno!
Q3 - I've seen insert boring bars like pic for lathe toolpost boring, in fact I use some with CCMT inserts & more flat faced shanks, but still of round stock profile. I see some with totally round shanks too. Doing the price math, its actually cheaper to buy an insert type 0.500" shank boring bar & cut to length & use the variety of inserts I have. Is there any difference cutting action wise between how a boring head would hold the tool vs in a lathe? (Ie. both boring ID's).