PLA won't stick to PEI build surface
I don't know what happened. I was printing just fine until just now PLA does not want to stick to my smooth PEI build surface. What I am encountering is the brim of a fairly large set of parts comes unstuck before the brim completes. I did the first layer calibration and that seems good. I washed the build surface with isopropanol. Then I tried washing with soap and warm water. Then I tried washing it with acetone. Then I tried applying a layer of hair spray. Then I washed again. Next I might need to try painters tape. Nothing I do seems to work. I am wondering if I managed to wear out or otherwise destroy the PEI surface or if something else is going on that I don't understand. Would someone please give me some clues on what I can try next? Thank you.
RE: PLA won't stick to PEI build surface
This you need to do:
1. Clean bed with dish soap, use a lot of hot water, do this several times. More clean then this you won't get.
2. First layer calibration needs to be 100%. If you are confused about this( I often am), print a few cubes, and start with a to high z live adjustment, then lower it by steps, then you will see the good setting.
Try a different roll of filament to be certain that it is not bad filament.
Make a picture for the forum, of your first layer.
RE: PLA won't stick to PEI build surface
Thank you. That helped a lot. I washed with dish soap and hot water several times and directly printed nine 50mm^2 single layer test squares. I didn't even bother wiping with isopropanol. Everything stuck very well although I could tell the center and front right was less firmly adhered than the other areas. The test squares on the left were very well stuck to the build plate. Also the test squares in the center and front right could be pulled apart while the test squares in the other areas were firmly melted into a single cohesive sheet. One other thing I could tell was that the front left test square had a slightly more bumpy surface while the other test squares were very smooth and flat.
RE: PLA won't stick to PEI build surface
Bumpy or waves, then you are to low.
Make pictures of your first layer, then forum users can give info about your first layer.
Do z-calibration, then try again. You can start to high and lower it , a little at a time. To low or to high sticking will get bad.
If bed is not flat, if you have octoprint there is a plugin to measure the bed.
To get bed more flat I did heat up bed to 60 degrees, then turn all bolts loose on the bed(a little), then tighten them down again.(do not tighten to hard the small bolts will get damage). With octoprint you can check the flatness again, or do a first layer calibration.