Request for advice about Adhesion for PETG to 3M 467 MP…
I’m printing at 255, .33 bottom layer, grid raft with 3mm spaces, 2 layers, 5mm extra raft rim using cura. I have dual extruders. I use e3dV5 heatsinks. Marlin firmware, OctoPi, cura 15.04.06 on mac.
It sticks well to the 3m film which is 0.46mm thick. (It is brand new and shiny. I haven’t scratched it up enough to make it REALLY stick.)
After about 0.97mm the edges begin to curl slightly. The second nozzle sees that and dutifully tries to pull the object off the bed (right side). After awhile it succeeds.
Meanwhile, using OctoPrint, I pause the print, raise the Z by 60 and let everything cool down. I then tape (with Blue tape) the object flat (2 corners were holding well.) I set back the Nozzle flow 10%. There are slight bubbles in the middle of the print where it isn’t sticking to the bed. I do G1X0Y0F3000, M84, push to carriage to [0,0],
G1X1Y1F3000,G1X0Y0,M119, make sure xmin,ymin are triggered, G back to point it stopped [x,y], raise nozzle temp, extrude and clean, G to print point and resume.
The warped spots cause constant creaking and eventually I pause again (layer 2.67).
I decide to heat the bed to 107 and started it up with normal nozzle flow. The raft laid flat on the bed. I paused, turned off all heat, placed a flat steel object and a brick on the print and blew a large fan at the bottom of the heat bed. The object was flat and adhered to the bed.
I started printing…
IS THIS NORMAL?
If I heat the bed to start, the PETG doesn’t adhere to bed very long. If I print on Blue tape the flow has to be perfect or it wads up into a ball of mess.
I’m thinking of using tie wraps (4 steel wires around the bed), stopping after a good raft base, tie it down and go.