We use an ordinary 1/8" carbide tipped blade, and cut everything with it, even aluminum and bronze. If I want to cut plexi, I grab one that has been sharpened (a virgin, in other words) because the aluminum buildup on the sides of the blade, however small, tears up the finish when cutting plastic an rubs "dirt" into it, making for more sanding later to "clean" it. The bottom line is that it doesn't matter so much what type, or grind, of blade you use, what counts is how
sharp it is.
My saw is a 17 horsepower monster (Delta Industrial, awsome saw) and turns a 20" blade, but that doesn't really matter, the feed rate on a manual table saw is established by feel anyway. The coarser (less teeth) blade you use, the slower the feed rate, and the easier it is to manually control. Another thing I didn't get into is that you want to raise the blade above the table only enough to cut through the part, plus 1/8"-1/4". (1/4" stock, raise the blade 1/2"). This aligns the cutting force as much as possible with the long dimension of your part, and makes for less chipping. In the same light, don't let the part vibrate (jump) on then table, hold it down against the surface for smooth cutting. This is true with any machining operation on plexi.
Sanding the edges before flame polishing is good practice, I forgot to mention it, (I can't remember everything when I'm typing fast).
The tiny "hairs" of plastic standing up on the surface melt into the scratches and actually give a better fnish than a smooth surface does when flame polishing, so sanding with coarse paper is fine. Clean any surface you want to flame polish beforehand, or you'll melt any dirt (including fingerprints) into the surface. Use windex.
Heat gun bending works just fine, it takes manual technique to heat the part uniformly so the bend is consistent, which gets us back to practice, practice, practice.
