From my limited expirience, temperature of the extruded material must be in some narrow window, too cold or too hot and it will clump. Even within the window, t

From my limited expirience, temperature of the extruded material must be in some narrow window, too cold or too hot and it will clump. Even within the window, the production of sticky hairs (what one would aim for in this case) varies a lot with temperature. I can also imagine that the material plays a huge role, but I cannot say because I've only really used PLA.