Wet filament test

Print it, dry the spool, print it again. Whatever changed is water.

Print it
Check print 1
Dry, print again
Check print 2

The print

64 × 26 × 27 mm, about 4.6 g of PLA or PETG, 17 to 42 min on the makers' standard profiles. Made for a 0.4 mm nozzle: the ring is one line wide (0.45 mm). No file for your printer? The STL is the whole test.

Print 1 in grey PETG: the left post wrapped in a band of hairs and blobs, rows of small zits on the ring, a long whisker on the right post and a thin string from the ring to it. — Print 1: Trček PETG from the open spool, on a P2S. Hairs, blobs and rows of zits.

Print 2, the same file after drying: posts and ring almost clean, two or three fine hairs and a few tiny specks left. — Print 2: same spool and file after 6 hours at 65°C. Zits gone, strings down to a few hairs. (Both printed before the ring got its thicker root.)

What you saw

Look for	Print 1	Print 2
Popping or hissingAt the nozzle while it prints
StringsBetween the posts and the ring
Zits and blobsThe ring, the posts, the end of the base
PinholesThe ring, held up to a light
Craters or fuzzThe flat top of the base

Dry the spool to its brand's own spec. eSUN publishes 50°C for PLA and 60 to 65°C for PETG, without hours; the other brands are in our drying table.

Fill in print 1

One print can already clear the spool: if print 1 shows none of these, it is not wet.