TLDR:
Trying to print a 2U rackmount faceplate (19" x 3.5" x 0.25") in 2 pieces and the edges are curling up, making registration of the two pieces impossible.
The Story:
Just for context, I’m relatively new to 3D printing and have rapidly learned it’s not a plug and play application. Be nice to me and explain your answers.
The problem is that the prints are curling up at the corners. Not just a little, but lifting > 2mm off the plate. This only happens after about 4-6 hours, and then the print head starts carving troughs along the outer edge as it works to deposit filament in new layers.
The design is not just a faceplate, it’s got other stuff on the back to hold various equipment, but I’m printing it face down. The plate is split into two pieces, the larger of which is about 11" long. I rotate it about 60 degrees to keep it more centered in the print bed. The two pieces need to print accurately in order to register to each other.
As near as I can understand it, the source of the problem is uneven heating/cooling of the model as filament is deposited, which creates an internal tension across the upper layer causing the piece to curl inward. I can reproduce it on some small pieces in high-quality print mode, but it does seem that faster and smaller prints suffer the phenomenon less.
I’ve tried:
- keeping the enclosure sealed up, and opened up for full airflow
- adjusting the nozzle temperatures up and down
- adjusting the nozzle fan speed down (this is NOT a good idea FWIW)
- changing the bed temperature up and down (initial layer and other layers)
- I meticulously clean the print bed for adhesion
- I’ve messed with print speeds a lot, but I want a high quality result…
- I’ve messed with infill some, and the thickness of the top and bottom layers.
The only thing I haven’t tried from all the various troubleshooting lists I’ve looked at is spreading glue on the build plate. That feels like a last resort and not a viable long-term solution.
I’m about at wits-end. I’ve tried many many prints and have a trash can full of bad starts. I have gotten one usable piece, but even that one was still… poor.
What advice can you give to get a good result on a big piece like this?