It was CCTree white PLA. I don’t think it really warped; it’s still flat even after removal. What I think is that it shrunk, as all filaments do when they cool. Now, to be fair, it was a large, flat, relatively thin print. In fact, it was the top for the ImpossiTable I previously linked to on Thingiverse. The top is about 7 inches in diameter and 1/8" thick. And the plate is just ordinary glass, less than 1/8" thick. I suspect the shrinkage was just too much pressure for the glass. That said, the adhesion using UHU was impressive to say the least. That’s why I diluted the next print’s UHU layer with water. We’ll see.
It is still quite amazing that it cracked.
#Ender5r You mentioned that you were using “picture glass” in another thread. Was it this glass that cracked or a factory supplied glass bed?
Oh, the picture glass for sure. I would be surprised if a factory glass bed cracked, exept if it was badly abused. The picture glass has 2 issues: [LIST=1]
Good points! I have seen many other materials, from PEI sheets, spring steel, etc. I can’t say any are good or bad, but the Creality glass has worked well for me. The only reason I purchased new ones was because of my mistakes, and wanted to have spares. It always scares me when I wash them in the kitchen sink, that one will get broken
re: sink washing: just be sure the temp of the glass & water is reasonably the same to avoid thermal shock. Borosilicate glass should be relatively immune to thermal shock (think Pyrex) but why take chances for nothing?
Thanks for the tip. I have never had a problem, but I usually wash all three of mine at the same time, the two Ender 5s and the Ender 5 Plus. I’m more worried about the transport from the basement where the printers are to the kitchen, then drying and back again. I am almost finished with my workbench build, so hopefully tomorrow back to printing.
This is the so called glass bed that stuck to my Ender 3 pro like sh*t to a blanket as the Texans say. https://www.amazon.com/gp/product/B07NVFSQGN/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1. I’ve decided that washing the Ender 3 pro is probably not a ghood idea and I will swear that I cannot separate it for anything. It will have to break.
#Ender5r There it is. I would definately not recommend any glass less than 3mm.
A few folks have used mirror tiles as they are quite thick (must be very handy to see how your bridging is performing too).
When I started useing higher temperatures, I swapped out my original Ender5 mag bed for an Amazon-sourced coated glass one. Installation required stripping away the mag surface and glue layer and cleaning up the bare aluminium bed. Some glass beds come with adhesive, which does away with clips, but means you have to take care of the bed in situ and let it cool down to pop the prints. When it does fail I will have to chisel it off, I guess. Interestingly the glass still flexes slightly as the bed heats up so you have to auto level with bed at the printing temperature.
Recently have added a mains-powered bed heater which works a treat and saves a lot of time.
Where I have experimented with adhesive, I found the cheapest PVA white glue to be effective, as is painter’s blue tape with super sticky TPU (to stop it sticking to the bed!). Have not had much luck with hairspray (not having much hair) so my machine is not covered in that either.
MrD
#Roon4880
Before you reach for that hammer, consider softening the adhesive with solvent.
Try introducing a little acetone along the seam between the glass and the bed: if it wicks in quickly, add more. Put paper under the lower edge to catch any runoff. Acetone is flammable. Do this in a well ventilated place away from ignition sources. Unplug the printer to prevent any accidental spark.
Do this right and you will save the glass and the aluminium bed from distortion and damage. Worst case you will end up cleaning off the glue residues and have to use clips to clamp the glass. Hope this helps.
MrD
I have absolutely no intention of unfastening it yet. I will wait til it’s a problem.
#Maximo101 Both the alu base plate and the glass will flex when heated, which makes ABL an attractive option. If the bed is warped at ambient room temperature, you can take the bed off the printer and lay it top down between two lengths of 2x1 and gently ease the dip out by pressing down in the middle. Too little is better than too much. Flip it over and test with a straight edge (i use a steel ruler). Rinse and repeat as needed!
If the glass is warped at ambient temps, I would be inclined to replace it. Bending as above will almost certainly break it!
MrD
I don’t have an Ender but maybe this video by DRVAX will help. https://www.youtube.com/watch?v=y_xCtxcwDrQ Someone in the comments used aluminum foil instead of a Post It note.
Cheers
CR-10 Mini Semi Auto Leveling G-Code by EdGoodson - Thingiverse This gcode works for leveling any printer manually. I just use a piece of E4 paper.
Thanks for referencing Dr. Vax’s video. That would be a good way to find any low spot and foil or a postit note should help and work well on a glass bed since you won’t be removing it as often. I do think you should go through the manual leveling with the bed at the temp you want to print, as they do warp when heated.
Thanks for the responses. The Dr Vac video is perfect except I’ll use apiece of aluminium foil.
I have had a few prints fail lately 3/4 through as the print must have came dislodged from the surface, using a larger raft fixes the issue, but now I believe the dip / warp in the build plate was partly to blame.
Have you tried a different filament? Is the area that it is separating where the dip is? Maybe try moving the placement in your slicer and see if it happens in the same location, but a different part of the print. Your bed temp should be OK, but you can experiment.
This is a puzzler. In addition to moving the placement of the part on the bed (good idea!), I’d get back to basics. Do your first layer prints look good and adhere well? Check extrusion: maybe the filament is thinner now than before and the printer is under extruding. Try printing the raft slower (fans off if they aren’t already) at 20 mm/s or less so the plastic has more time to relieve stresses. What is the first layer thickness and height of the raft?
Let us know how you fix it!
Cheers
Welcome to the world of 3D printing.
With the aluminium over packed under the glass I’ve had a few successful prints without issue, to be safe I put some tape on the raft though but after the prints finished the raft was still firmly stuck to the bed until it cooled.
I’ve also decreased the raft line spacing on the bottom of the raft for more surface area.
Always learning something 