crush depth

Eryone PETG (Part 2)

See Part 1 first!

I realized I never checked to see if the extruder was actually consuming 10mm of filament each time it asked for 10mm. In other words, I never calibrated the extrusion multiplier for the material.

I printed a simple vase mode box with a 0.5mm wall width, and the extrusion multiplier set to the default value of 1:

Box

I then measured the thicknesses of each wall of the resulting print with calipers. This gave me the following measurements:

0.52mm, 0.6mm, 0.52mm, 0.48mm

Averaging those numbers gave me 0.53mm. Dividing 0.53mm by the original target width of 0.5mm gives 0.53 / 0.5 = 1.06. In other words, for every unit of filament the extruder is trying to consume, it's actually pushing out around 1.06 units. This is likely down to the compressive nature of PETG; PETG is more elastic than PLA, and compresses when forced through an extruder. Effectively, I'm slightly over-extruding. I then set the extrusion multiplier to 0.5 / 0.53 ≈ 0.9433962264150942 and printed again. This time, measuring the thickness of the walls gave me:

(0.52mm + 0.48mm + 0.5mm + 0.48mm) / 4 = 0.495mm

That is, the average thickness of the walls is off by 0.005mm, which is likely within the margin of error for these digital calipers. Hopefully, this should increase the quality of prints with the Eryone PETG as I continue to try to determine the right settings for reliable, durable prints that don't look like someone took a blowtorch to them.

Continued in Part 3...