Wanting to Vgroove mill some low cost material that will be painted - rosettes for door/window frames. The commercial ones are out of pine I think. Have a small desktop cnc mill and tried it with a cheap HF Vgroove router bit. The wood was so-so and the result was horrible. Looking at the bits edge it has a slight reverse taper so no cutting edge at all. Think the bit came that way - haven't used it much that I recall.
Forget where I read it but apparently this is how some bits are made. Seems like I should have a sharp edge for a smooth finish. What speeds and feeds should I be using? I used about 8000 because that's the highest speed I can in low speed range and was concerned with torque in the high speed although in soft wood it should be fine for torque. Have cut aluminum in low speed range with no issues (with end mills).
If I double the RPM and double the feed rate with the finish improve? I had slowed the feed rate so thought that compensated for the lower RPM but could be wrong.
I am including a few pics of the bit. In third one you can see the slight reverse slope area on the leading edge of the cutter.
This is not production - just a small project to do about 6 pcs for my own use. I know I probably need to buy a better cutter but don't want to spend $70 for a tool with replaceable edges so something like that if it was a production job.
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