Does somebody knows why this happen?
Some help please! May it happen because of bad filament quality?
Looks like filament is popping. Do you have a different brand to try??? I had that happen with my first roll which was very cheap Chinese stuff
Perhaps a bit of over extrusion
My knee-jerk thought was that it could be due to lack of retraction, but I also saw similar issues before when I had filament that had apparently absorbed too much moisture. And you’d get these bursts, but I didn’t have it as much as you’ve got.
You have “Randomize Start Points” turned on. Turn it off.
Is that option on slic3r? I couldnt find it.
And i use to find those spikes on the same layer, usually on non linear movements.
It looks like it’s just moisture but @ThantiK could be right. Try baking your filament.
I had some old filament that started printing out like that, figured it was due to moisture. I turned down the extrusion temperature about 10 degrees and it seemed to help.
Looks like pause zits from poor acceleration planning. Are you using a delta with marlin and lcd?
I agree with ThantiK, randomizing starting points will cause this exact problem. You can also run a temperature calibration for your filament to see where it looks the best.
would guess moisture but this is the first time I heard about randomize starting points… is this setting exist in Cura?
What firmware are you using??? I got this problem with my delta. I’m agree with @adam_paul
Possibly the PID for your hotend is not tuned correctly. Do you see temp fluctuations on the hotend thermistor?
The plot of the temp should be nearly flat. If it looks like a sine wave you need to tune the PID.
Possibly moisture. Try and bake your filament in the oven. I usually do it with filament that I don’t use for a long time. ABS at 80C for 2-3 hours. PLA at 60-70C about 2-3 hours
It’s almost definitely the start to each layer that’s causing the pock mark and ‘randomise start points’ is causing them to appear all over the place. If you turn it off randomisation, you’ll just end up with the seam in a line up the print instead. You also need to do something to make the start point a bit smoother. Retraction seems most likely. You might also have an option to make the start point internal rather than on an external wall?
Solved, decreasing the speed and the retraction
@adam_paul Bingo, marlin+delta+lcd, and 32 microstepping
Marlin often can’t keep up with delta math, LCD, and 32 microstepping. Try switching to Repetier.
Or switch to a 32bit controller. You might also try a lower layerheigth, or is your part quite small/large magnification?