Since it's a CNC router, the bit will be turning at a VERY high speed. Probably too high for teh aluminum laminate you are cutting. if you only want to use air, you MIGHT consider using a vortex tube, but i think the real issue is that you need to get the cutting tool turning at the correct speed for the job you are trying to do. It's likely turning WAY too fast. I'm not sure where you might find a vortex tube, "Airtools" MIGHT have them. If not, you can likely build one pretty easily if you have a lathe.

Good luck.