This was my first shot at aluminum. I have to cut four slots .125" deep in a .250" thick piece of 5052 aluminum. The tool is a 1/4" 3-flute carbide ZrN coated end mill (equivalent to Carbide’s 201Z). The slot width isn’t critical so I bumped it up to .260" in the hopes of using adaptive clearing to spiral though each slot. Fusion wouldn’t do that - it kept giving me an “empty toolpath” (I assume .010" isn’t enough to let adaptive clearing work). So I used Fusion’s Slot instead and stepped down through .010" at a time at 60ipm, 17500 RPM (settings based on what I found here.
The first slot cut okay. I’m new at this so I’m not sure yet what it should sound like. It lifted out of the first slot & started into the second slot, went about an inch & froze because (I think) it melted the aluminum. I shut it down & sure enough, the cutter was full of aluminum.
Am I right in thinking that the melting started in the first slot; then when it lifted into air to move to the second slot, it cooled and hardened which caused the jam in the second slot?
Afterwards I plugged this all into GWizard & it’s telling me that with 3 flutes & 17500 RPM I should be going about 105ipm! If I reduce to 2 or 1 flutes the feedrate drops into more practical territory. Seeing all of this seems to explain what happened.
My original thought was to use the 1/4" end mill because it’s the biggest I could ‘fit’ in the slots, and for rigidity. I have a 3/16" single flute carbide end mill - for that, GWizard says about 38ipm at 17500RPM, .010 doc. Is using that and a different cutting strategy a better way to do this?