(Usiing 0.8mm nozzle, with 0.35mm layer heights, everything printing at 40mm/s. Flow rate at 95%.
But an unacceptable number result in air print, totally fustrating after 5 hours our of 24 and wasted plastic.
IN all cases, the filament is ground down in the extruder. Its not deformed below the extruder drive, which makes me think I do not have problems with heat coming back up the hot end; rather the hot end is not melting plastic fast enough and the extruder is grinding?
This occurs with two manufacturers of filament, and same Gcode, but it must mean my system is close to some limit (even when successful).
Assuming feed rate too high for hot end to melt plastic, I have reduced rate to 40mm/s and increased temperature to 250 and was getting some success.
Always prints raft, first 25mm worth of layers no problem but then something happend.
So the three explainations I can conceive are:
- 1) still pushing too fast, maybe slow down or increase hot end temp even further
2)I think there is a correlation with some blobs on surface; sure blobs can cause problems but can they stop extrusion long enough to cause grinding
3)I wonder, if there is a small amount of warping (I've not noticed any), but if its extruding along a long line of plastic, and if there has been sufficient warping so that the nozzle is not .35 above the last layer, but the last layer has warped up against the extruder, coudl this cause the problem?