Skeinforge Quicktip: Cool

Running out of things I know about Skeinforge– once I get the other post on the Raft dialog I think I’ll switch gears and do some scripting tutorials.  (Anyone who’s got useful tutorials for Skeinforge, Blender, or other digital fabrication design tools, let me know in comments and I’ll see about putting it up some Tuesday.)

But about the Cool dialog.  Checking enable cool and setting the minimum layer time will cause the print head to “orbit” around the printed area rather than immediately printing the next layer.   Skeinforge has M-codes for turning a 3D printer’s cooling fan on and off, so if you’ve installed one on your printer, clicking both “turn fan on” and “turn fan off” run the fan only during orbit times, which is good because constantly running a fan pointed at the extruder head can freeze the plastic, leading to failed builds and stripped-filament-related swearing.

Without a fan, this setting can cause trouble if the printed area of a given layer is very small.  The purpose of orbiting is to get that hot extruder nozzle away from a new layer for a while, but if the area in which the head is orbiting is tiny, the nozzle actually never gets far enough away for the plastic to freeze, and meanwhile is twisting the plastic into a crunchy helix.  (Anyone have a setting that makes the orbit the same size as, say, the raft?  That’d really help…)