Yeah, the chips can re-weld. I've had them weld so hard on my scroll saw that the sheet actually cracked somewhere else when I tried to break it off at the cut. The trick here is to use a larger tooth blade for things like scroll saws, band saws, and jigsaws and keep the speed down as much as possible. The bits of acrylic that are carried out of the cut help to carry off excess heat as well. When cutting effectively, you should get warm chips, not melting.