> So the "normal" fabrics we use (i.e. silnylon, spinnaker, cuban, and etc) will ALL work with a hot knife?
Yep. I have cut all of those.
If your hot knife has a variable temperature you should do some tests on scraps before you start on the real cutting to see what temperature is best for the fabric you are cutting. I need a different temperature for 30 gsm parachute cloth compared to 1000 denier Cordura! Cutting speed also factors in.
I cut on some cheap 3-ply. It ends up with many slight burn marks. Don't do it on carpet, polished floors, concrete, ...