Top arm and leg printing sharp

[holyloktar]

I've printed this new design a few times and it comes out really sharp on the top arm and leg, not like the bottom ones. I've adjusted a few settings, slowed the print etc. but it continues. Have you run into this issue?

[DrLex0]

Those parts haven't changed compared to the original models, so this is not an issue specific to this remix.
This is caused by the fact that extruded plastic has a tendency to curl upwards on sharp overhanging corners. Some plastics are worse in this regard than others, for instance PETG is much worse than PLA. Things that may help to reduce this issue:

• Add more cooling: either enable the extrusion cooling fan or increase its speed.
• Print in thicker layers. This issue usually gets worse with thinner layers.
• Change extrusion temperature. It depends on the material whether a lower or higher temperature will improve things. For PETG in my case, it helped to print hotter.
• Get a pointier nozzle. Nozzles with a large flat underside dump more heat into the surrounding material, which makes this issue worse.