New milling motor Proxxon FBS 240/E upgrade to Kress 1050 FME-1

[JAZZCNC]

Agreed but generally this is good advice. I use 3 flute 8mm corn cob to rough. The rest are 2 flute.

Certainly anything higher than 3 in alu generally is a problem for most.

No it's not generally good advise because depends on the type of cut and machine, along with several other factors like cooling etc.
Slot cutting is worst case for most because chip clearence is less so people use less flutes to give more clearence. But if the machine is strong enough and cutting parameters are correct then 3 flute will work just fine and give higher MRR. It's generaly only good advise to those that don't know there machines capabiltys.!
Like wise for finishing or cutting with plenty of chip clearence like profiling then multi flute cutters work great provided the machine can handle the higher feed rates. People go wrong by using multiflute cutters is wrong situations or more often much too low feedrate. If run correctly in right places multiflute cutters give a much better finish.