Shattered bed (ABS Juice)

[pmeyer]

So: ABS Juice definitely works amazingly well.

Removing a print last night (maybe a 3" circle flat base) actually pulled a shard of glass off of the bed, maybe half the thickness of the bed, 1"x1/2". No big deal, I thought, I'd planned to put a PEI sheet on top of it anyway.

The next piece I reprinted away from the chip. Tapping that piece off this morning (much more carefully, slowly!) the whole bed just broke into two pieces.

Good sources for replacement glass?
If I'm going with PEI as the work surface anyway, can I dispense with the glass and go with a flat metal bed? Steel? Aluminum?

[Xenocrates]

I'm using plain aluminum (well, not quite) as a bed material with PEI overlaid. The potential problem is flatness. You may want to either face it flat, if you have access to sufficiently large mills, or else attempt to sand it flat as best you can. I recommend starting with something like MIC-6, which is more expensive (and 1/4 inch is the thinnest I think), but starts out pretty close to flat, which means less effort for you. I wouldn't use steel, as it's got worse heat transfer properties.

As far as the glass goes though, SeemeCNC is probably the easiest source, although if you know a glass cutting shop, or a stained glass shop (such as Delphi Glass), you can ask them to cut you a disk. Although most of those places don't have borosilicate in sufficient sizes, so the bed will be even more likely to shatter, due to thermal cycling.

[hubrigant]

When using such thick aluminum, did you need to use a 24v power supply for the bed to get it to heat up in a reasonable period of time?

[Xenocrates]

I find that it currently takes ~30 minutes to reach temperature, if it reaches it on it's own. A large part of that could be hostile conditions. Ambient temperatures in the workshop where it lives aren't controlled, and the chamber on my Max isn't heated (yet. Few more days I hope), so the bed and hotend together need to heat up the air enough to make the temperature gradient workable. Note that that's first print of the day. Later prints take less time to heat up, as the air in the chamber is already warm. I've also bagged the printer with a plastic painters tarp (Don't do this unless you have confidence in the solidness of your chamber, if that thin plastic gets to the hotend, it may cause a fire), which also increases speed. I haven't yet gone to a 24V bed, but I plan to soon. Especially with up to 5 more inches of snow coming, every bit of extra heat I can get on the printer is nice.