Originally Posted by FEandGoingBroke
cut slower or lighter. u are melting the aluminum
That's the real answer, and the lube answers are an attempt to keep it cooler. I (usually) don't use any coolant or lube with my carbide cutters on cast aluminum and my cutters stay clean, but my RPM are never "maximum", and my cuts are deep.
I had no issues with buildup using an air die grinder, but the air exhaust was forward at the work. When I used electric for some jobs, I had issues (even with lube) until I built a speed controller from a dimmer switch, outlet, gang box and cord. You quickly find a speed that is high enough to not chatter, but allows a smooth deliberate cut. Between the slightly slower speed and aggressive cuts, the bit gets hot, but the aluminum doesn't heat as much, avoiding galling and buildup. HIgh-speed light cuts tend to heat both the bit and the aluminum
If you can't control the speed, you might try clamping or banding a small compressed air hose or tube on your tool, aimed directly at your cutting area with generous flow. That may keep the temperatures low enough. Lubricants can help, but holy cow - what a mess if you can avoid it. Also, once it starts, it's hard to stop as aluminum sticks to the cutter (micro) even after cleaning, and it wants to stick more to itself when hot again. A vicious cycle. HTH