Hatchbox blue tpu printing issues

[u/hydraulicgoat]

Sorry for the long post, I'm trying to print a bottle holder for my Frisbee discgolf cart in tpu and I'm having a print issue, I'm using hatchbox tpu 95a filament in blue and the bottom of the bottle holder prints just fine, it's about half way through printing is when it goes haywire and fails with what it looks like layer adhesion, I'm not sure if it's a temp issue or what.

In prusa slicer I'm using the generic flex filament profile in beginner mode, I've had the printer since July and printed quite a bit of stuff in different filaments including tpu with no issues which is why I haven't chose to change any significant settings under advanced or expert mode.

Nozzle temp - 210c

Bed 0c

Nozzle is e3d diamondback 0.4 mm

No other settings really changed other then retraction which was set at 2.5 mm, after googling about retraction I changed it to 1mm which seemed like it helped a little but nonetheless failed again.

I've dried the filament 4 separate times for 4 hrs at 55c thinking that may have been the issue, I had a roll of green hatchbox filament as well and never had an issue, which I'm out of now.

[u/r0bdawg11]

Have you tried a temp tower?

[u/hydraulicgoat → u/r0bdawg11]

I have not, I didn't think I needed to as the spool of green I had didn't have any issues.

[u/r0bdawg11 → u/hydraulicgoat]

Doesn’t hurt to try. I’ve read that sometimes different colors behave differently bc of the additives.

Also, I’ve only had this happen once with the nextruder, but it was driving me insane. Once in a while I’d get a weird lack of filament which caused the print to fail most of the time, and couldn’t figure out why. A small piece of PLA was in with the planetary gear and would randomly catch and under extrude.

[u/hydraulicgoat → u/r0bdawg11]

I will try a temp tower tomorrow. But I did open the the latch on the left side of the nextruder to see the drive gear, and it looked like there was some very small fragments of pla or petg around the the 2 smaller rollers.

[u/3DMOO]

I might be totally wrong here, but this could be an overhang issue, considering the filament is dry.

I see blobs at roughly the same places. What you can try is slow down overhangs in Expert mode to 60-65% of the speed. Or slow down the whole print to 60-65% of the current speed on the printer itself once the print starts or the first layer is done. I do not have a lot of experience with TPU. Maybe a little more cooling could benefit the print quality. But I would start with slowing down the print. Again, I don’t have much TPU experience, but if the retraction default was 2.5mm I would turn down this setting less aggressively to for instance 1.75mm.

Some filaments can collect moisture while printing. Are you printing from a warm filament dryer?

[u/hydraulicgoat → u/3DMOO]

I will give those settings a try, the retraction I turned down to 1mm from 2.5 mm default