I’m printing TPU with .8 mm nozzle and having troubles with the first layer. There are gaps between the layer lines and it looks pretty bumpy.
I’m printing with .3 mm layer height and my print speeds are at 20 mm/s.
Any idea what I could do to improve the first layer?
Hm, not sure if it’s (just) the grainy photos, but the skirt line looks pretty uneven. Is that a fresh roll of TPU, or if not, how did you store it? TPU is hygroscopic (attracts moisture), so if you left it outside a drybox it probably got wet. A quick test to confirm that would be to just extrude some in thin air. If you see/hear any sizzling/bubbling, that’s the trapped water turning into steam.
General tips for printing TPU: print it slow and with as little retractions as possible (if you’re on a bowden setup). You could also try slightly increasing the extrusion multiplier.