Hi all, running into an issue here I just can't seem to solve.
I'm printing a hollow model in PLA using 3 perimeters/outline shells, no infill at all. No matter what I seem to do, the outline shells just won't bond to each other, such that you can easily take an xacto knife (or maybe even by hand) and pull the outline shells apart. This completely decreases the durability to the point that even applying slightly pressure to most parts of the print cause it to bend as if it were just a single wall thick. I've searched for awhile on the forums with no luck (either they never solved the issue, or their solutions don't seem to work for me).
Some background info and what I've tried: I'm printing at 120 mm/s with an FLSun Delta QQ-S. Thinking it was an underextrusion issue at such a high speed with the shells not bonding to each other, I raised the temperature from 190 C to 200 and 210 C without any success. I upped the extrusion multiplier from 0.9 to 1 and then 1.1. It certainly extruded more, because the print was covered with tons of blons and zits, yet the outline shells still didn't bond together. I wanted to continue printing at high speeds, but afraid that it just wasn't going to work, I lowered the print speed to 80 mm/s and lowered the outline shell speed to 48 mm/s. Absolutely no improvement whatsoever. I changed the outline overlap percentage from 15% up to 50% and higher, but I assumed it wouldn't make a difference since it seems to be only for infill (and the print confirmed that). I even tried manually adjusting the extrusion width just to see.
So between making a dozen test prints or so adjusting temperature, speeds, extrusion multiplier, and extrusion width with varying results on surface quality but 100% the same no-adhesion between just the perimeter shells, I'm at a complete loss.
I was able to get a pretty beautiful print, nice surface detail, very, very few deformities, etc., with the only significant issue still being the outline shells not bonding to each other. No matter what settings I tinker with, nothing seems to help. I tried slicing and printing in Cura instead just to see, trying to use the same exact settings from S3D (temp, speeds, flowrate, layer height, etc.), and the shells bonded wonderfully and I ended up with a solid, durable print through and through. So what could I possibly be doing wrong in Simplify3D?
Any suggestions are greatly appreciated, thanks!!