What type of material do you guys use for picture frame glass or a clear guard on a table saw sled? I found some plasticy stuff at lowes that says it is 10x stronger than glass but I have no idea what it is. Acrylic maybe?

It was probably lexan or similar its usedsa lot in signs instead of plexiglass because it is stronger and more flexible. Also does not get brittle either.

Probably Lexan. It really is some tough stuff. It does scratch, though. I'm using it on a gun cabinet and I do fear for scratches. Besides, as far as I know, it's not made with anti glare. For that reason, glass is really a better alternative for pictures.
Incra Jig uses Lexan for guards on their I Box jig.

I'm assuming I can cut the stuff with my table saw? I would also guess that I should predrill with countersink bits to avoid cracking?

I would use glass for picture frames but lexan or plexiglass for safety equipment.

It's most likely an extruded acrylic. If it was a polycarbonate (like Lexan brand), it would be marked as a polycarbonate. Not likely a cast acrylic sheet either. Up to 3/16" thick material it can be scored and snapped.

It can be cut on a TS. I use a 60T, and cut with the blade high.

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If you are framing photographs, then don't use anything...no glass, lexan, nothing.....In my younger days, I worked for a studio, and we would never cover photos, no matter how big....humidity will get between the photo and the glass, and ruin the photo.....when paying $300 or more for a 24 X 30 of your wife, it is something you did not want to ruin.....

What's the reason for that?

Blade high makes the angle that the blade hits the thin sheeting closer to square. It is less likely to lift and tends to cut more smoothly.

I use Plexi in framed artwork that I will be shipping. Sure, glass is a better solution--but plexi or lexan definitely are better choices if you plan to let UPS or FEDEX play with it. . I just finished 4 30x36 frames this week and they have .1" plexi installed. I cut the sheeting with my regular 40T Onsrud TC.

+1. Just to add, that the more vertical angle provides less of a cutting thickness, which means less friction from blade contact, which means less heat, and less of a melting problem. I try to do all cutting with the brown masking paper on or the polyfilm protector that some sheets come with.

If I'm cutting thicker stock, like 1¼" polycarbonate to be used for bank drive thru's or teller windows, I might use a 32T.

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