I’m working on a print which has a lot of fine lines using the Aerostruder, which tends to cool off the print head pretty quickly. I’m getting some tiny gaps while printing that I want to get rid of, but I already have the temp at 255, and I’m not sure if I should go any higher. Should I try for 260 or is my problem possibly with something completely different?
Where are the gaps? If its where infill meets perimeters, that can usually be resolved by increasing the “infill overlap” parameter slightly. Cura2 calls that “Skin overlap percentage”, under “Infill”. If the gaps are between infill lines, then it may be under-extrusion – which could benefit from calibrating E-steps, increasing the extrusion multiplier, or slowing down a bit. If the gaps only occur in one direction (i.e., skin meets perimeter on right/left but not top/bottom), then it may be a mechanical issue like a loose belt.
Can you post a photo that shows the problem?
The gaps seems to be randomly distributed along long sides. I think that that it may be due to the extruder temp being high and making the filament too weak to hold a line. I have it at 255, since the Aerostruder cools the head off by around 10-15 degrees. If I put it at 240, I start to have adhesion issues between the layers. Assuming that’s the problem, I’ve been trying to find the sweet spot between 240 and 255.
Those look like the kind of “holes” I get when retraction is too high, or (on slicers that support it) when coasting is set too high.
For a quick test, try turning off retraction (and coasting, if your slicer has that). That may cause blobs or other defects, but if the holes disappear you’ll know retraction/coasting was the cause and can fine-tune the values.
But it doesn’t seem to happen when the nozzle is moving over a non-printed area. It will be laying down a long line and I’ll hear a “pop”, and there will be a small gap. Online resources suggested that means moisture in the filament, but it only happens with some prints and not others. I’m still leaning towards a temperature problem, has anyone experimented with trying to over-heat HIPS to see what happens, and what the ideal temp might be?
I’ve always understood HIPS to be one of the least affected by moisture, and moisture usually presents more widespread problems than your photos indicate. But the popping noise could be moisture or it could be voids in the filament. What brand filament? As a test, you could pull off a length of filament and bake it at about 60C for 3-4 hours, then try another print. That would confirm or rule out moisture as the cause.