Being a beginning machinist getting into this to make some fun stuff and maybe a little extra money I seem to have an endless well of questions. Heres this one. I was talking with a friend who is a machinist about why 2 flute endmill's are preferred over 4 flute or other. He had a variety of reasons, but none of them seemed particularly convincing. He also said that 3 flute endmills are much better and they leave a much better surface finish than 2 flute. So I bought a bunch of 3 flute endmills, the cheap ebay kind, and have now been having some problems, which Im concerned are due to my choice in number of flutes. The problem is the endmills will clog with aluminum and then of course, it all goes downhill from there. I am using a Sieg X3, at the max rpm, with a 1/4 3 flute endmill, with a koolmist system. The feedrate varies between 18-24 ipm. The feedrate was suggested by my friend as well and is much faster than what MasterCAM is suggesting. To be honest, I havent worked the feedrates for myself yet, but seeing how fast people like Hoss is running his it doesnt seem like it should be a problem. So... whats better and why, 3 flute or 2 flute, to work in aluminum