Dry boxes sound like great idea given the humidity numbers you shared. Am using some Rubbermaid cereal sized ones. But could have CNC’d something to hold multiple spools…
Bought the same clear 3mm ID, 4mm OD from amzn. Definitely less drag on the filament, also feels more flimsy than regular PTFE. The flimsy PTFE might help reduce twisting forces on the carriage too?
If/when fittings bite through the thin walled PTFE, and/or something else kinks/compromises, then, I plan on upgrading to 4mm ID 6mm OD. But will need to ensure the PTFE doesn’t impact carriage motion. Back when figuring this stuff out, I noticed larger hole thick wall PTFE seems to be used on Pantheon and other pricier machines.
Related post…
For “reverse Bowden”, I don’t know if Capricorn is worth the extra $$, it’s blue, so there’s that…
Edit:
For direct, 3mm+ ID feels way better than 2mm ID for reducing filament drag, so that’ll help reduce friction the extruder has to overcome (feeding and fast retractions).
For “Bowden” on my Ender 3 max, am happy with the 2mm ID Capricorn I use there.