Posted by Ron V on September 21, 2016 at 17:17:47:
In Reply to: Tos F06 chatter posted by Kyle on September 21, 2016 at 09:23:00:
To me, 400rpm seems way too fast.
For a 100mm diameter hob, 45-55rpm would be the max I'd be running a HSS cutter through something like K1045 carbon steel.
I use a constant that has always seemed to work for me, if using HSS cutters; divide 4500 by the hob diameter (in mm) and the result gives a suggested rpm.
If it's a carbide cutter, then that would of course allow a much higher speed.
If your machine is built for it (has a hydraulic ram to take-up the backlash in hobbing head's lead screw); climb hobbing can actually help to reduce cutting-induced vibration/harmonics. Climb hobbing generates less stress/load on the drive train than conventional hobbing.