I’ve since switched over to a 0.4mm nozzle (was using 0.6mm previously) and ran the print with identical settings other than extrusion width and layer height. I think all of the same problems are still evident here, albeit less noticeable with the smaller extrusion width and layer height. My main concern is the underextrusion that is happening in areas where retractions happen very close to each other.
PETG doesn’t seem to retract very well to begin with. Wiping probably pulls some of the filament from the hotend. There is a setting in Slic3r that allows you to extrude a little extra when restarting after a retraction that could help.
@Greg_Nutt , the thing is that the problem only occurs in specific areas of the print – when I change a setting like that it just causes issues in the areas that are printing well.
I realize this isn’t an ideal part for FDM 3D printing, but that’s part of the reason I’ve been using it to get things tuned in. I’m starting to think that I should do what @NathanielStenzel said in my last post and create a folding version that would print really nicely and be substantially stronger.
What slicer are you using?
Also I suggest changing your acceleration and jerk settings. The default on the printrbot is too high. I had good luck with 16 jerk and 800 acceleration.
I second @Stephanie_A --I think I was running around 500mm/s2 for acceleration; I also ran a retract speed of 45mm/s and retract distance of 2mm when printing PETG on my Simple
@Stephanie_A , @Ishaan_Gov , @Alan_Thomason : I used Simplify 3D for those prints. Currently experimenting with Slic3r as an alternative. Interestingly it does seem to be eliminating some of the issues I was seeing.
Those were the acceleration and jerk you were using for the X/Y axis? My print bed is fairly large/heavy so I’ve had to dial the X/Y axis acceleration way down. honestly haven’t played with jerk much at all.
@Stephanie_A , ah – I’ve apparently already dropped the jerk down to 10mm/s^3 from the default of 20mm/s^3. My massive Matrix Precision bed clearly isn’t doing me any favors here.
@Matthew_Kelch I think that somewhere in Slic3r you can select “random” for layer starting point. This will prevent any starting/stopping defects from lining up and being so visible. Regarding the weight of the bed - the lighter weight the better.
