Tearing the PEI right off the Bed

Putting this under hardware since its mostly about the adhesion of the PEI to the bed.

I use PC MAX since it produces parts that I can use in production rather than just for prototypes. It is very strong.

The problem is that it pulls the PEI right off the bed. This is a problem I have been struggling with for a while. I am now on my third piece of PEI and second bed.

In the picture below the Bed and PEI are brand new from Lulzbot. You can see what happens. The 468 MP is not strong enough.

In another post on this issue, Mikronano suggested using thicker PEI. I have a piece of 1/16th inch PEI and a sheet of 468 MP, but haven’t had time to clean up the other bed. And I have my doubts that it is going to work. Seems like the 468 MP is the weak link…

486mp is the weak link. no one has come up with a high temperature capable replacement that performs better though. Specifically one that will stick to PEI. if you find one, please let us know.

If your prints are sticking that firmly, can you bump up the Z offset a bit?

I would try to control the curling more, then it might not pull the plastic off while the bed is hot and weakened the 3M transfer sheets adhesive properties.

How would you go about controlling the curling more?

You will have to keep the air around the polycarbonate warmer while printing, then cool it evenly&slowly when you lower the air temp for removal. Also make sure you are using the PVA glue stick, you want it to give and not the adhesive on the PEI.

The printer has an enclosure and heater. Running it at 42C. Polymaker recommends 50C. The thermostat on the heater is preventing me from going above 42, but I have wondered if I changed out the thermostat, and run the temp up to 50C whether that will help.

I am using PVA.

The photo was taken about half way through a 30 hour print - so the warping is occurring during the print job.

Changed out the PEI to a thicker piece and this has gone a long way towards resolving this problem.

Go to the end of the following post for more info and a picture. https://forum.lulzbot.com/t/pc-max-problems/4458/1