Michaels has front open frames with rounded edge glass for $5. It is no borosilicate, and can be dangerous after a few heat cycles, but the price and convenience is great. The 8x8 fits my Prusa kit perfectly.
I bought regular window glass from ace hardware. I’ve had it upwards 100c and no problems yet other than I stepped on a couple hah. I got 3 pieces for like 10 bucks or so cut
I sat on one a while back…
My $5 glass bed exploded when I tried to bring it up to ABS temp (it gave out at about 90c). For PLA you should be fine.
I have not had a problem around 110, but my bed is weak and it takes a long time to reach that temp.
Mirrors seem tougher and can be cheap from Michaels/IKEA. I bought a fancy boro glass and it chipped in a couple of months. Not worth it at all.
I had a mirror crack at 90c as well. Not really tougher.
I’ve gone through about 4 mirrors, none of them have fully cracked (except one that I dropped the pliers on!). Mostly what happens is cooling ABS with glue stick under pulls a chip out of the surface. Depending on where the chip is, they tend to be toward the outer edge of larger prints where the stress is highest, I can keep using it for quite some time even chipped. I would like to investigate chemically hardened glass, I guess this would be like cheaper gorilla glsss.
Also picked up a couple of mic6 cast aluminum plates, but I’m just not sure how it works as a printing surface adhesion wise.
Great, well I’m already a glue stick convert. Good to know it works with Al too.
I’ve been using the glass from dollar store picture frames. It’s on the thin side, so not very tough, but I’ve had it to 110C many times without a problem.