What bit should I use for cnc routing/milling blue insulation foam with my dremel?

I'm making a desktop cnc mill using my dremel as the milling tool...what bits should I use to mill foam? How about for cutting thin(3/32 or so) plywood?

My woodwork and engineering tool making experience, tells me you chose your cutter by the ability to dispose of waste chips. Very soft foam, you take out large chips, for wood, smaller, for metal, smallest, finest teeth, and going finer as in a grinding cutter. Then you decide on sharpness, with soft foam, you need razer sharp cutters, otherwise you just tear off hunks, leaving roughness. So on soft foam, if your cutting teeth are too small, they can get clogged up, then rather than cut, they just rub, and your cutter overheats. I do a lot of such shaping in MDF, which is considered very abrasive due to the glue used to make it, for that always use TCT. Back to the foam, in metal working, soft alloys, you always need a kind of lubricant to stop the metal chips sticking to the cutter teeth and then WELDING on. I wonder if you might want to use non-stick spray used in cooking and baking, on your cutter? Just a spray on the cutter now and then, to make it non stick, as in non-stick-frypan. If it is the foam I am thinking of, why cut? Maybe instead of the Demrel, maybe a very hot rod, or disk attached to a heating element, but insure you dont get affected by the fumes. Then, if you use the suggested cutter above, could you get one machined up to the same profile but smooth? Seeing its cnc, you just run that around afterwards, it rubbing, will heat it up, then it will sort of polish your work. PS, be aware that if the shank of such a cutter expands from the heat, it may do something to the collet of your Dremel.
slider388 (author) 7 years ago
hmm, that actually is probably a bit more suited for my purposes since I'm using the black and decker dremel in my mill...also they look like their size is great. Thanks a lot!