Hi All,
I'm fairly new to this group but I've had a CNC Shoptask for about 6 years.

I'm having a bad time parting off 6061 on the lathe. I'm using a very solid tool mount, a sharp HSS 1/8 X 1" blade. The problem is chatter. I get the cuts made but the chatter is fierce. The diameter is 2" down to 3/4".

I've tried top rake angles from +7 to -7 degrees, tool positions from center to .015" above center, speeds from 60 t0 1100 RPM and amazingly none of this seems to make much difference. The chatter is the same under all these conditions which leads me to think I'm way off in something I'm doing.

Facing, turning, and drilling are no problem. I do get some chatter Boring.

Appreciate any suggestions.

Jerry