Blobs and Zits on Highest Point of Print

Finally finished the first part for my AMS riser, however I noticed that the print quality went down hill when the printer got to the final apex of the print.

I’m reading that this the zits are being caused by insufficient print cooling. So, I’m trying to adjust the cooling settings, but I noticed that my part fan is set to always be 100% for all parts of the print, and yet while I’m actively printing part 2, I see that the part fan is not on at all.

Am I missing something?



I’ve had a similar problem when trying to print a set square with point up. I think the cause is the fact that at the top, there is a lot of heat build up in the object, and because the filament path is not as long as lower down, the filament does not have time to cool between layers. Also, (if you have a p1s) the aux fan will be blowing warm air from above the build plate, as the plate is lower than the fan intake.

I think i am having a similar issue when trying to print a 0.5mm edge. I havent had the issue on my prusa so it must be settings that i need to change

The Prusa, i guess, is without an enclosure. The other thing to consider is the ambient temperature. Some can not print pla in the summer, its softening temperature is too low.

It’s as debonr suggests, a cooling problem. I found two ways to address this problem for anyone curious. :

  1. Go to the GCode and adjust the height bar on the right to the appropriate height, and add a gcode command of [M220 S50]. The S stands for speed, but I’m not sure what the M stands for. I think melt temp?
  2. There is an option to adjust a height range in the Process > Objects area of the Preview pane. From there, you can adjust toggles to whatever speed you want. There is no overarching toggle for all print speeds, but since this seems like a problem with the walls, I think you can adjust those two settings? I’m not sure if the infill has to be changed as well.

Hope this helps someone else. Haven’t had a chance to test it yet as I’m still in the middle of a 12 hour print, but will try to report back on my next print if anyone is interested.

One thing I’m still curious about is why my Part fan won’t stay on when I toggle it on. It autoshuts down within a couple seconds of being toggled during a print, so I imagine the OS is telling it to shutdown based on some sort of higher commands. Not sure what the rationale is there?

Fortunately turns out i just neeeded to use arachne