TPU printing problem

[bazzy]

Hello, I can’t understand why I have not been able to print the TPU for some time.
The first layer is fine, but the following ones seem burnt, and the supports do not come off.
I tried to do various interventions but nothing changes:

• changed material (Z-FLKEX, 3Djack TPU …)
• done calibration of the plate
• changed thermocouple and temperature sensor
• changed nozzle
• Clean extruder gear

do you have any idea why?

(Zortrax M200plus, Z-suite 2.26.0.0, Z-suite Beta 3.0.0.0)

[Pawel_Zortrax]

Hello,

Do you have such problems with other materials as well?

Did you try changing the hotend, or changing the platform offset if it’s to close to the platform?

If possible please send me your zcodex file used to print.

Best Regards

[bazzy]

with Z-Ultra the prints are ok.
yes, i tried to change hotend
I have not tried to change the offset because until a few days ago the prints were fine even with the Z-Flex
send z.code in PM

[Pawel_Zortrax]

Hello @bazzy

Did you trie to change the platform offset, yet?

You can as well try performing the Platform Maintenance if the offset helps.

Your model printed at our side without issues.

Best Regards

[Norman]

I tried printing with Z-flex and part way through the raft the filament feed seemed to dry up. I checked the internet and there were articles with the same issue but they focused on the print settings and mechanical failures in the feed sprocket.
Flexible material needs a very smooth feed from the spool due to its high friction especially around any even shallow corners.
The following are all necessary to improve reliability of the filament feed.

1. Where the guide tube fits (m200+) into the filament out sensor and the print head it was being compressed
   a. Use a 9/64th drill bit (3.4mm) to relieve the inside of the tube simply twisting it with your fingers in about 10mm
2. The angle the filament as it comes off the spool is critical as it goes into the filament sensor.
   a. A 35mm spacer was fitted under the sensor to move the feed alignment to the centre of the reel. This halved the angle when the filament was coming from the outside edge of the reel.
3. There is a spool holder for Z-flex on the Zortrax site but
   a. It needs to be printed in nylon for very low friction, especially when the spool is full and at max weight.
   b. The vertical height should be extended by approx. 70mm (lower the spool) which again reduces the angle from the reel to the filament sensor.
4. The clips that hold the feed tube to the print head ribbon need to be minimal
   The result, a more reliable feed although it will never be as smooth as hard filaments.