Hey Neo, most of the tools I've seen in the above package are 2 flutes. I guess that due to the small size itself. I have never had any clogging issue, fiberglass doesn't tend to stick to anything when dry. The amount of copper is really minimal so no problems with that either. I have no experience with alloys coatings on PCB tools. However, plain carbide tools seem to last forever so that might not be even needed.
Adding a bit of my own 2 cents, I would be concerned with runout on the spindle to be use for this purpose. Not only precision is needed to make accurate cuts, it can also save the tool. I got lucky and my homegrown spindle turned out to have a very low runout. My Porter Cable, on the other hand, has .002" runout - simply unacceptable to work with these tiny tools. The other issue I've had is trying to get the PCB mounted flat on the mill table. Just a small variance in height and it could mean the difference between a great copper cut or no cut at all. I need to find time and make a jig to hold the PCB with 4 adjusting posts for precise leveling.
Give it a shot. Mount a flat-nose, center cut end-mill on your router, take a few minutes adjusting Z if needed and cut in at about .0028" deep
Regards,
JR  |