Help, Generic TPU prints keep failing. I need a good

Bambu Lab P Series Troubleshooting
1

I need to print the gaskets for AMS riser vs.

As I do not have BL TPU, i had to use a locally manufactured brand. With my Ender 3 S1 Pro i always had great quality prints with this brand TPU. The spool was freshly opened. Despite, I have put it in dryer for almost 48 hrs. Final readings were 9-10%.

Before start printing the gasket I wanted to tested with an STL i had been printing almost every month With my S1 Pro.
TupperTPU.3mf (709.8 KB)
It turned out as hot mess every time. I tried different speed setting etc. Ask Chat GPT to create a Generic TPU profile for me. Every attempt fail.
Then i found a video pointing to a profile in printables. I saved its profile as my user profile. It contains a custom gcode.
3DBenchyTPU-original.3mf (2.4 MB)
and printed the cap with this
Tupper BL-3mf.3mf (433.6 KB)
The supports were hard to remove but it printed very well.
Then i tried to print gasket with this profile.
AMS Riser V2 - Gasket - TPU(2).3mf (1.5 MB)
I could not take photos while printing as it was too dark inside but starting form the first layer some sections were perfect and some sections were somewhat fuzzy and or under extruded. I waited until the end to see if it would turned out usable. Spoiler no.
Although majority of the top surface looked ok the section with fuzzy texture remained.

gasket Close up1
gasket Close up11152×2048 326 KB

gasket Close up2
gasket Close up21152×2048 485 KB

![gasket|281x500]
(upload://sH7XwTPxIPl9JA4t328nIhLiKFA.jpeg)
gasket
gasket1152×2048 353 KB

Small part of the thin flap just torn itself. The mounting peg were looking problematic and even with a soft touch they got broken. They were hard and not soft like the rest. The timelapse does not reveal much. There was a video which system does not allow me to upload and i could not find the photos.

I decide to make calibration with orcaslicer. The PA test could not print much. When i tried to Flow test it failed to adhere to bed instead of pushing out a regular line they were looking like P1S was trying to print with only stringing.

This one is with Generic TPU as filament and generic print profile.
Flowrate Test - Pass1.3mf (66.5 KB)

Generic TPU-default
Generic TPU-default1152×2048 688 KB

Generic TPU-default
Generic TPU-default1152×2048 688 KB

Custom filament and custom profile I used for Tupper did not work either

Porima TPU + Custom print Profile
Porima TPU + Custom print Profile1152×2048 629 KB

The default bed temp was set to 35c. tried 40C and 45 C. nope. Lowered Z during the first layer. Nope.

As prints creating a lots of stringy mess i brushed and sponged with soap under hot water everytime.

I packed my S1 Pro. If only I had a room to install it again i would happily print TPU with it after.

The TPU I am using is A98. Not even soft. Can you please check and recommend some solutions and Share your External spool TPU print profiles.

2

TPU is hygroscopic, it will suck up moisture from the air. It generally must be properly dried before use. Have you done that?

3

@Lenyo

It has to be dry atm.

The default 35C bed temperature with Textured PEI is not working. When the bed is 45C. It somehow stick to bed. This was suppose to be Flowrate 1 test. I assumed the default flowrate of 1 was also way off and thats why only -10 looked better.

custom45c1
custom45c11152×2048 262 KB

custom45c2
custom45c21152×2048 185 KB

custom45c3
custom45c31152×2048 244 KB

custom45c5
custom45c51152×2048 549 KB

With the same settings after adjusting the flow rate i rerun the test and again nothing stick to bed at all. After every print i clean the bed with soap and sponge crazy.

PLA sticks and prints great but not TPU.

4

Hmm, my bad, I didn’t read well enough. It sounds like it should be dry.

Did you do a quick test for partial clog (that -5 looks terrible)? Manually extrude filament at your print temp and make sure it comes out straight down. Make sure the nozzle is clean and the filament path is unobstructed and feeds smoothly and easily.

What is causing this pattern?
5

I might have found the root cause of the problem.

guilty
guilty1152×2048 464 KB

As nothing was coming out of the nozzle i suspected a clog. I performed a few cold pulls with PLA. When I try to put TPU back into the extruder it did not want to come out. I removed the Y splitter. When i ran PLA through it there was a clear grinding feel. Probably the splints in it were catching TPU and do not let extruder feed. Without it extruder had no difficulty loading and extruding TPU.

I restarted the flowrate 1 test. First layers look much better so far.

2 Likes
6

I think we posted at the same time

7

My search for better preset continues. I do not want to double post. Please check some additional details in the following post.