Why do my prints have warts??
Printing on a newly upgraded MK4S with MMU3. Newly as in several weeks. Was running a 3S for a few months prior to that. I have only been printing for maybe 4 months now so I have much to learn. I appreciate these forums as I have already learned a lot.
I mostly print in PETG and I live in a fairly dry climate (Boise) so moisture has not been a worry for me thus far. However, that being said, we have had some foggy winter days as of late and I have noticed that some of my prints have turned out with leprosy or warts or whatever you want to call them. You will see on the temperature tower picture they seem to be happening consistently at all those termperatures. My theory is that my filament has absorbed enough moisture now that as it's moving thru the hot end it's forming little tiny pockets of steam that "pop" when released from the nozzle, thus causing these lumps and bumps. This is Overture light grey and it seems to be the worst offender. Printed some Overture yellow today in the PETG-TPU test (you see in the bumblebee bullet at the bottom) and all went well there. No bumpies in the yellow but I do see them in the TPU which have read is also fairly thirsty. Would you agree that these bumps are a result of wet filament? Does moisture cause such things?
RE: Why do my prints have warts??
Bumping this post. No ideas out there about why my prints have these bumps all over them? Anyone seen this as a result of humidity or other reasons?
RE: Why do my prints have warts??
I haven't yet had moisture issues with my PETG, but my brother in law gave me an incredibly wet spool of TPU that printed in almost a foam texture. Really bubbly. A new spool of black overture TPU prints beautifully smooth though, and after repeated drying sessions of the inherited spool, its appearance has improved greatly, with only occasional bubbles. I expect that foggy and/or rainy conditions would absolutely cause your filament to absorb moisture, so if I were you I would find a way to dry your filament just in case. I also live in a dry climate, so I've been able to avoid buying my own dryer so far, but I eventually will need to, especially for the rare wet spells we have. I always keep my filament in zipped bags to improve my chances, but I know eventually it won't be enough since they are exposed while printing.
-J
RE: Why do my prints have warts??
Check the seam position setting. You have the position set to Random. Set it to Aligned. Print settings -> Extended -> Seam position.
RE: Why do my prints have warts??
Moisture in filament can cause these warts, even in PETG. I received an incredibly damp spool of PETG (it was my first try of PETG!) and I couldn't get it to print well at all. Warts, bumps, blobs, you name it. After drying the filament at 65C for 6 hours, the same spool printed fine. FYI that spool was Prusament. I was astonished that it was so soggy. Yes it was sealed, and had a tiny silica gel pack in it. While printing it would hiss and pop - a sure sign of moisture in the filament. After drying - no sounds, no warts, no crazy behavior.
RE: Why do my prints have warts??
Very good to know, thank you. Not only that moisture will cause this, but also that new spools of filament can show up wet. Looks like I need to get more serious about drying and keeping dry. Thanks all for your input here. I appreciate it.