TPU - Issues

The manufacturer recommended that I increase the temperature to a higher temperature than recommended. Currently my tpu93A is printing at 248 degrees

I too am in the exact same position. I wonder if a recent update caused this? Very frustrating for sure.

Bonjour
C est ma premiĆØre impression en TPU, j ai l imprimante depuis 3 mois.
J ai lu pas mal sur le sujet, j ai donc change les vitesses d impression.
Max 20mm/s c est parfait.
Mais de temps en temps l imprimante se bloque . j ai eu un message trop de couple pour le moteur.
L AMS tire trop sur le filament (il me semble) donc je dĆ©roule un peu moi mĆŖme quand je vois cela.

Are there any solutions in the meantime or have all attempts failed?

Iā€™m asking because Iā€™m currently also trying to do large TPU prints on the X1C with the printer open.

In the past, I have only ever made smaller prints that turned out pretty well. In addition, the hotend was always completely cooled down before printing (obviously important because of heat creep). When I have larger prints, the first 10 to 15 layers are usually good, after that the filament is no longer fed properly and the print becomes unstable. I have the same problem with Bambulab HS-TPU. This is particularly unfortunate because the roll cost ā‚¬40. I always unwind the filament so that it doesnā€™t have to be pulled off the roll externally. It doesnā€™t work in the AMS. If I set the speed too low, around 15mm/s, this also seems to cause a problem. It works best around 18mm/s to 22mm/s. Higher temperatures, around 250Ā°C, seem to work better, but are obviously not the solution to the TPU problem. During printing, the extrusion continues to decrease so that the printed part is far too unstable, even if the print can be completed.

exactly the same issue with my bambu p1s tried 2 different makes of tpu
filament hardly extrudes at all the most it printed is 3 layers of a shoe sole im trying to make as i have one leg shorter than the other
frustrating gonna give it a go on good old ender 3 pro

I had this problem with a certain 95A filament. Exact issue.
Even tried a larger nozzle. Ended up drying filament over night, maybe half the next day and I havenā€™t had that reappear. Also used Bambu HF TPU and no issues.

I have a Sunlu S4 and feed the filament directy from it.

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Iā€™m having the same issue. I used the TPU preset from printable in the pas with great success. I printed several dozen parts without issue.

Then someday it started doing the under extrusion every one is describing. I tried drying the filament for several day without success. Ran cleaning filament in the nozzle to clean it. Still doing it.

I disassembled the extruder tonight and the gears lookā€™s fine. I have about 2500 hours on the printer. Iā€™m thinking of replacing the extruder assembly but after reading previous post Iā€™m not sure.

It almost feel like a update issue that everyone is experiencing.

In my case, the PTFE from the AMS to the printer has worn through. Now Iā€™m wondering whether this could also be the cause of poor extrusion with TPU. Especially when some people write here that it worked initially and then stopped working after several hours of operation. It may help to replace all the PTFE tubes.

on ne doit pas mettre de TPU dans lā€™AMS

What could also be the cause is running it through the AMS. BL does not recommend it.

Replace the PTFE tube, and take a look at all the rest. Good chance theyā€™ll all need replacing if you havenā€™t.

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We never put TPU in the AMS as it cannot pull TPU back and deforms it too much. However, it is very likely that the PTFE to the print head is subject to the same wear as the PTFE from the AMS to the printer, which could possibly correlate with poorer TPU transport if the PTFE is worn or abraded on the inside.

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I also had the same problem. The TPU filament flow would stop in the middle of the print. I also believe the problem is because of the extra force needed to pull the TPU filament. Because the external spool does not turn easily, the flexible TPU filament becomes thin when there is too much force, and the thin filament causes problems when it enters the extruder .
To resolve this, I used a combination of two models from Makerworld to improve the external spool holder so the filament feed to the extruder would be easier, and so far it seems to work very well.

The name of the two Makerworld models I used are below:
1 - Spool roller for Bambu external spool holder (you need to use bearing for this one)
2 - External spool holder / Externer Spulenhalter

Had this problem recently. Do not print out of heated dry box. Printing off external spool holder now. Also had to cut off nearly 10 yards of filament because my TPU got so jammed up in the dryerā€¦. I compared the diameter of the filament and was surprised how much thinner it was in the stretched out portion of it. No joke i threw away nearly 3 actual yards of filament to get to full diameter.

Not denying your experience but I print mine directly from S4. With the Siraya Tech tpu almost forced to.

S4 may let the filament out with less drag that the Eibos Easdry.

The rollers in my S4 are not really good. Filament rolls off with difficulty when I want to print directly from the dryer. That is not usable. I still have to work on a solution, which I will probably print. When I have time.

I have purchased new bearings for mine. I havenā€™t gotten to installing them on the rollers yet, Iā€™ve toyed with looking at the rollers in the back of the AMS but havenā€™t tried to fit them yet. I have extras, just have had a few more things pop up to take care of.

I had similar issues, but I always dry my filament to under 30% and run it out of Sunlu S2 dryer with a Boden tube to a Y splitter, howā€™ve I keep the temp at 62C so it doesnā€™t get to soft after itā€™s been dryed. Iā€™ve had great results using Overture HS(flow ratio 0.97, Vol Speed 9mm^3/s) and Priline(.96, 10mm3/s).
Any non high speed filament Iā€™ve been having slight issues with though, even when I lower my Vol speed down to 3.2mm3/s.
Id suggest also trying to maybe adjust the flow values. And try keeping the door closed but open the top slight

This was futile. I have the wrong bearings. Lubricated the ones it came with, no real difference. The AMS rollers would work but too short. Not giving up though.

thatā€™s strange because all the TPU stunt weapons Iā€™ve been making for this movie, Iā€™ve put it into the dryer box and left it running and itā€™s given me really clean mace head prints so far, but I will keep an eyes on this.