I received a replacement unit yesterday and I’m up and running again. They said it would be a refurbished unit but it looks untouched so I’m very pleased. Besides sending a link to an incomplete repackaging instructions, Glowforge has been outstanding to work with and very fair. $200 for the repair an $200 for shipping seems more than fair to me. Not to mention they got the replacement unit out within a few days of the notification.
I use social media to promote companies with good customer service and to warn people about companies that aren’t good. Glowforge has been way above par in every aspect of this ordeal and I’m happy to share it.
EDIT: Turns out the problem is probably related to the ceramic magnet and not the Glowforge lid. Check out this video… https://youtu.be/QhlmKHbPFhU
Put tape around your magnets if you use them.
I accidentally dropped a 12 gram magnet from 18" above the lid and it annihilated my glass lid assembly. Just a little word of warning… don’t handle anything hard anywhere near the glass on your printer or you will have 5000 tempered glass beads for souvenirs to remember the occasion
Tempered glass is amazing in its strength. I had a sliding door insulated unit I needed to dispose of, so I put down a furniture pad, put the unit on it and folded the pad over it and hit it in the center with a hammer. The hammer bounced. Hit it 3 more times with increasing force. The third time the hammer bounced almost as high as I had swing it from - I was astounded!
After thinking about in disbelief for a minute, I tapped it on the edge and it exploded.
The magnet had to land exactly right/wrong. Probably would have a hard time replicating that unfortunate incident with a 12 gram weight.
I worked in auto assembly for more than two decades. I have dropped windshields and had them bounce and ring like a bell, and on the other side shatter from the slightest touch when near the edge. Sometimes technology can be amazing.
Tempered by definition means that the glass was heated to near sagging temps and then quickly cooled. As that outside cooled the glass on the inside gave way but as the inside cooled there was no give from the outside so the inside shrank more than the outside and set up huge forces so when hit with a hammer that is an even force as @PrintToLaser described it does not increase the forces but eases them a bit on the other side. However the slightest crack or deep scratch that unbalances those forces will cause the place adjacent to be unbalanced and give way and so forth so fast it will be like a bomb.
It was not the weight but likely a scratch that caused the break. You could drop a diamond ring on it and get the same effect.
The ceramic magnet is basically the same as hitting tempered glass with broken porcelain or spark plug insulators. It’s harder than the glass and can penetrate the surface on a microscopic scale and that’s all that’s needed to pop it, no high forces required.
Also popular with cyclists and motorcyclists to catch the attention of idiot drivers not paying attention to the road and causing near misses. Tossing a handful of steel ball bearings underneath a rolling vehicle makes quite a racket too.