Issues with my mill
I have spent the past couple of years converting my round column mill / drill to cnc. Did all the good things, lapped the ways, geckos, ballscrews, etc. X and y went great, but z .... The machine had sat for 2 years and the quill had rusted to the point where it seized up. I disassembled it completely, removed the rust from the quill with fine sand paper, honed the inside of the head stock casting and reassembled everything. I finished the z axis and am now cutting under full 3 axis cnc control. But......
This thing cuts horribly. Vibrates like crazy when I cut. Never did this before when manual milling.
For example a 2 or 4 flute 1/2" endmill (HSS or Carbide) at 2000 rpm .030 DOC and 8 to 10 inches a minute chatters very badly. To the point that I need to wear ear plugs it is so loud. Faster or slower feed and rpms do not seem to help. Even light .010 DOC and 25% stepover does not improve it. It seems worse climb milling then conventionally cutting. This is a R8 spindle with a 2 hp motor and I am only cutting 6061 aluminum. I should be able to plow through this stuff. So what did I do?
I checked the spindle and made sure the thing was tight. Snugged it up a bit more, but it's tight. I can't feel any play. Did i bend something removing the spindle? I could put and indicator on it and check for runout, how much should I see typically? Other things to look for? It does not feel as though it is in the table or base, but the head itself and then radiates throughout.
Driving me crazy. I spend alot of time and money on this to be disappointed.
Thanks for the help.
Dan
Check out what I am working on at www.routerbitz.com!