Started moving some of our parts over to our newly acquired SQT15M and so far it's been a real treat to program and operate.
The part is 6" OD, 3.125 ID and 1.2" thick 6061-T6 from Sapa. The issue were having is with the surface finish on the ID bore, 2-3 parts will have a great finish and gage perfectly then the next part looks like dog shit and and is undersized due to chip marring.
Using a C style (don't recall the designation at the moment but we have been using them for years with fabulous results) kenn 5410 polished high positive inserts .032" nose radius, coolant is at 9% directly at the cutting tip.
Roughing at 2000 SFM, .100" DOC, .020 IPR, Finishing at 2500 SFM, .012" IPR and have tried everything from .005" to .075" finish amount with the same result. Spindle is clamped at 4000 RPM.
My son is running the same part from the same batch of material using the same inserts and cutting parameters on a QT8 and not having any issues. :confused:
Now that I've had diner and put my feet up for a bit I'm thinking that the problem maybe in the "windmill effect" of running a larger chuck 8" as opposed to 6" and taller soft jaws 2" as opposed to 1" could be blowing the coolant stream away from the cutting tip although looking thru the window it's hard to tell.
Tomorrow I think I'll cut the jaws down to 1" and clamp the RPM at 3000 and give it another go.
Any other suggestions or tips?
The part is 6" OD, 3.125 ID and 1.2" thick 6061-T6 from Sapa. The issue were having is with the surface finish on the ID bore, 2-3 parts will have a great finish and gage perfectly then the next part looks like dog shit and and is undersized due to chip marring.
Using a C style (don't recall the designation at the moment but we have been using them for years with fabulous results) kenn 5410 polished high positive inserts .032" nose radius, coolant is at 9% directly at the cutting tip.
Roughing at 2000 SFM, .100" DOC, .020 IPR, Finishing at 2500 SFM, .012" IPR and have tried everything from .005" to .075" finish amount with the same result. Spindle is clamped at 4000 RPM.
My son is running the same part from the same batch of material using the same inserts and cutting parameters on a QT8 and not having any issues. :confused:
Now that I've had diner and put my feet up for a bit I'm thinking that the problem maybe in the "windmill effect" of running a larger chuck 8" as opposed to 6" and taller soft jaws 2" as opposed to 1" could be blowing the coolant stream away from the cutting tip although looking thru the window it's hard to tell.
Tomorrow I think I'll cut the jaws down to 1" and clamp the RPM at 3000 and give it another go.
Any other suggestions or tips?