Warped Prints

[jimc]

yes you really need to measure every roll of filament in a few spots and take an average. this value must really be changed with every roll. your slicer will use this to mathematically figure out how much plastic needs to be extruded. if you have it set to say 1.75 but you filament is actually 1.78 then your printer will be extruding more plastic than it thinks it is. you end up with parts that are out of tolerance or too much plastic being pushed around on each layer which can cause the nozzle to drag, hit your part or just sloppy top surfaces and walls. its very similar to just turning your extrusion multiplier way up or down.

[Geoff]

yes you really need to measure every roll of filament in a few spots and take an average. this value must really be changed with every roll. your slicer will use this to mathematically figure out how much plastic needs to be extruded. if you have it set to say 1.75 but you filament is actually 1.78 then your printer will be extruding more plastic than it thinks it is. you end up with parts that are out of tolerance or too much plastic being pushed around on each layer which can cause the nozzle to drag, hit your part or just sloppy top surfaces and walls. its very similar to just turning your extrusion multiplier way up or down.

I leave mine set at 1.8, after nearly 2 years of trial and error I find with this particular machine it's a pretty safe bet. I also live in a humid environment where filament can tend to swell.

I dont measure my filament anymore, I go through that much unless it's giving me issues I just don't bother really. Nozzle drag shouldn't be happening anyway if they are levelled and the other hotend isnt actually in use, and if it use you can use dribble supports.