Glass flaking/delamination when priting on bare glass

Some users have encountered flaking or delamination when removing parts when printing on bare glass. We recommend printing with either the stock PET surface, or with the new PEI print surface that some of our more advanced users are using with great success.

Thanks!

Claudio


I have this problem. I’m printing on whatever surface came on my TAZ4 Bed - not sure what that is on the glass - but it just started flaking. I’m attaching an image of the flaked spot.
Can you provide more help?
Is the PET surface you mentioned what I have on my glass? Is that what is flaking? Can it be replaced?
Where can I learn more about eh PEI surface?
THANKS

I just ordered my TAZ 4 today and joined this users group to learn fast. Please explain the “new” Material and where I can get it?

jrochelle. That is your PET tape. That amount of tearing isn’t really an issue.When it gets worse you can always replace the entire tape layer.

OK - good to know. I found the documentation to really lack in general descriptions of what I actually have - didn’t even know I had PET tape on top of the glass. That scar is only about 3mm square - and hasn’t caused any issues.
When I’ ready for new PET tape - where/how to I get replacement?
How is PET different than Kapton, that has been suggested by others?
THANKS!

PET film and instructions can be found here:
https://www.lulzbot.com/Pet-Tape-12x12-sheet-green-5-pack
https://www.lulzbot.com/support/installing-pet-your-glass-bed
https://ohai-kit.alephobjects.com/project/c5dc9083-39f5-442e-886e-c0200484e2d6/#step_4

In my opinion you don’t really need the pet tape. I mix scrap ABS with acetone and spread it on the surface of the bare glass before I start printing. Take a small bottle, fill it with scrap pieces of ABS (use white ABS) and after it turns to a gooey consistency, spread it on the table with a rag or cloth on the area the part will be printing. This will keep your print from warping when using ABS, and its also much easier to take off the table without having to pry at it for an hour.

PEI. Period.

I stuck some on my other printer and it made a believer out of me. All the struggles with kapton, glass, hairspray, glue stick, tape, squash… gone. Heat up the bed to recommended temps, print, cool and pop the print off.

Since the printers are in the basement office adjacent to the furnace… I never thought Acetone would be a good mix for the environment. Breathing the vapors as it evaporates to leave the thing layer of ABS can’t be good either.

My TAZ5 has the PEI bed from the factory… Great move, AO.

I second that PEI praise.

I had PET tape, and even with laying down ABS glue, I still had issues with parts warping at corners and edges.

I put a 1/16" thick PEI sheet down, now I haven’t had any warping since (at least not that I could notice) and I don’t have to mess with acetone.

I recently built a KITTAZ and with all the positive feedback on PEI, I never bothered with anything else. I installed a 1/16 inch (0.06") thick sheet of PEI using 468MP adhesive. For the most part the PEI lives up to it’s name but leveling has become problematic with what seems like a concave down bow in the middle of the bed. I am thinking that the PEI sheet may be a bit too thick to assume the flatness of the glass substrate. Of course, it could be an imperfection in the glass but I am going to try a thinner sheet of PEI, perhaps 0.03". The 468MP has bonded the PEI to the glass so well that I have to suffer the cost of new glass. Be warned, test before gluing :wink:

As an FYI, I removed the 0.06" PEI sheet and replaced it with 0.03". It worked like a charm. It would seem that the thicker PEI sheet has a bend in it that is not fully straightened even when glued to glass with 468MP adhesive.

BTW, I was able to remove the PEI from the glass fairly easily with WD-40. A tip a got from ‘gapdev’.

When I first got my printer I removed the PET tape and shattered the glass bed. I was not to impressed.

Here is an article I posted on how to reduce the damage to the bed after each print using a brim that reduces the surface tension of the part on the bed.

https://forum.lulzbot.com/t/spineless-brim-makes-removing-3d-part-easy/1682/1

Hope this helps,

Spineless

Had no luck getting parts to stick to the glass plate. Tried some painters tape (a trick used on one of our other 3d printers) and have had better results. One can find the blue painters tape anywhere.

I have mostly used our Taz with the PET tape with great success, but at one point when the tape was getting badly torn up, I used the Taz for a while without the tape. I used the factory recommended ABS/Acetone slurry with moderate success. However when we were demoing the Taz at the Maker Faire, we ran out of acetone and the slurry got thicker due to evaporation. At the end of the day the last demo print was left on the build plate. The next day when I tried to remove it, it was stuck really hard. I tried prying it off and when it did release there were several places on the bed where the glass had chipped off in thin chunks that were stuck to the bottom of the part. The build plate and the heater had to be replaced.

the lessons learned:

  1. Don’t let your ABS/Acetone slurry get too thick!
  2. Use the PET tape (or the new PEI) and not bare glass
  3. the Aquanet hairspray method works fairly well for getting prints to stick without risking chipping, but not as well as PET tape and slurry for large difficult to print parts.
    4)If you are having difficulty releasing a print, heat up the build plate to soften the plastic and the bond to the glass. Don’t keep trying it cold if it is hard to remove, or you might have to replace your glass build plate AND the heating element too.

speaking from experience,

Dan