Print Temp

I’m having trouble printing Benchy. I’ve researched and experimented, but for the life of me I can’t seem to correct it. I assume it’s temperature related, but nothing I do works. Here’s my latest attempt.

I’ve watched it print, and have noticed that overhanging areas, like the lower hull section, or the the tops of the arches over the doors, curl up as it’s printing. Even the top stack was soft and moving around as the nozzle moved. The best I can tell from my research is that this is a temperature related issue, but I’ve tried high and low extruder temps (215-240), bed temps (100-110), and fan speeds (40/50-80/90), and no matter what combination I use I keep getting the same result.

This attempt was printed with Lulzbot HIPS, nozzle @ 240, bed started at 110 and dropped to 100 after .5 mm, fan speed @ 40-50%. It’s also worth mentioning that I’m having trouble with bubbles in my PEI sheet (pictures on this thread:, but since it seems to print the wheel-house walls well enough but still has the same issue at the top of the arches I don’t think it’s related.

Any suggestions?

You’re printing the stack and the thin housing walls fine, with maybe a little overheating. Those are the pieces that would indicate a temperature issue. It looks like overextrusion to me.

I actually thought that at first and tried dropping the flow rate to 90%, but still had the same problem on the perimeters with had under-extrusion on the infill.

Here’s an example I stopped short when I saw the corners starting to curl the same way. If you look close you can see that it’s having the same issue on the perimeters, and the infill is a bit wispy.

I had similar issues with the HIPS and kept trying until I got a good print. Try this…
Reset your profile by switching back to the HIPS quickprint (standard) then go back to advanced settings mode again…

Change these settings:

Print Temp to 230
Bed Temp to 100
Filament Diameter to 3.05
Flow (%) to 100.0
Layer Height (mm) to 0.2

Let me know how that turns out for you. This is black HIPS printed that way on my Mini

I may have changed the initial layer thickness and width as well, can’t remember on this one (and not in my notes).

I’ll give that a try. Thanks!