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Superfly Cutter
- Thread starter ddickey
- Start date
Depending on your feeds/speeds and DOC/WOC, I think you're getting some vibration. I suspect the head is bouncing up and down, or the column is flexing - the marks that appear as a radial pattern in the upper part of the second photo look like the cutter is doing a 'bite-skip-bite-skip' routine. The fly cutter may simply be too much of a shock load for your mill frame.
The other thing is you didn't mention - or I missed it - what you're using for lubricant or coolant. The second photo appears to have some galling/smearing that could be an indicator of chips sticking to the cutter or the cutter getting hot.
About the only thing I can suggest - short of seriously reinforcing the column with triangulated braces - is to take another light cut after tightening everything up. Set the cutter to cut about 0.005-0.010 deep and tighten the Z-gibs until it won't move. Tighten the Y-gibs same way. Take a cut in X using plenty of lube (WD40 or kerosene if you're not running flood) and see if it's any better.
Do you have a big bullnose endmill? say, about 1/2"? If that surfaces better than the fly cutter (ignore pattern - just the surface finish/scratches) then I think I'm right about the frame simply being too floppy. What RPM and IPM for those cuts?
The other thing is you didn't mention - or I missed it - what you're using for lubricant or coolant. The second photo appears to have some galling/smearing that could be an indicator of chips sticking to the cutter or the cutter getting hot.
About the only thing I can suggest - short of seriously reinforcing the column with triangulated braces - is to take another light cut after tightening everything up. Set the cutter to cut about 0.005-0.010 deep and tighten the Z-gibs until it won't move. Tighten the Y-gibs same way. Take a cut in X using plenty of lube (WD40 or kerosene if you're not running flood) and see if it's any better.
Do you have a big bullnose endmill? say, about 1/2"? If that surfaces better than the fly cutter (ignore pattern - just the surface finish/scratches) then I think I'm right about the frame simply being too floppy. What RPM and IPM for those cuts?
Makes sense guys.
No coolant. 1400 rpm. I tried a slow medium and fast feed (manual). Quill locked. I just adjusted the gibs but will try locking everything down. The diameter is set to the smallest. I think it is 2". I do have a bullnose endmill.
I wonder if the body has anything to do with it. I believe I made it out of 12l14.
No coolant. 1400 rpm. I tried a slow medium and fast feed (manual). Quill locked. I just adjusted the gibs but will try locking everything down. The diameter is set to the smallest. I think it is 2". I do have a bullnose endmill.
I wonder if the body has anything to do with it. I believe I made it out of 12l14.
For aluminum, try 2500RPM and 15ipm at 0.01" DOC (superfly). Spray liberally with WD40 while cutting, at least for this round of testing.
If there's flex, the tool body is probably the last thing. You've got head movement, table movement, column flex, and so forth before you need to worry about the tool body. Maybe I missed it earlier, but what brand/model is the mill?
That looks like when I tried to mill with a drill press and a Chinese X/Y table. Yuck.