Print quality / filament quality

[joma77 0]

Is it possible to evaluate the quality of the the filament (PLA) based on the print? What should I pay attention?

[jhertzberg 19]

Only to a limited extent, since often the optimal settings for a different brand, or even a different color of the same brand, will vary slightly. Some things are obvious, like color inconsistencies, debris, and pocking, but things like underextrusion may be your printer settings.

If I am not happy with a print the first time I use a new filament, I'll do some debugging. I'll print a small calibration object ~50mm high, and raise the temperature about 5C every 10mm, starting at 10C below the stated temp for the filament. Or, I might slow the printer down to 50% speed, and increase it by 10% every few mm of layer height to see if/when underextrusion begins.

This all assumes that you are inspecting the filament before use. You should check the filament diameter at several spots with digital calipers. A variance much greater than +/- 0.05mm from stated diameter will leave you with overextrusion at the high end and underextrusion at the low end. You should also check that it does not snap too easily when bent. I have received filament that was so brittle that the last quarter of the spool was unusable because the filament continually broke as it went from tightly wound on the spool to straight entering the feeder.

Concerning that benchy, it's pretty good, but without seeing the nozzle while it printed I can't be sure why you got that cluster of blobs right above the slight underextrusion, or the unevenness above the door. You should probably remove any obvious material from the outside of your nozzle, perform an atomic pull to clean the inside of the nozzle, and try it again.

Edited December 9, 2016 by Guest