MK4s Loadcell Trips with TPU Loaded
I am using ESun TPU 95A. When this filament is in the printer, the Z axis will lower a few MM, then stop, lower a few more, stop, eventually crashes the firmware and goes to red screen.
Loading a different filament will solve the problem.
Has anyone else experienced this?
Firmware 6.2.4 , first time printing with TPU on mk4s
Is there a increase sensitivity setting somewhere?
RE:
Which of the available TPU profiles did you use, as there is no exact profile with that name for PrusaSlicer?
I have a spool of black eSun TPU 95A. When I first tried it using it on my MK4S with the profile for SainSmart TPU (230 °C) the printer had a nozzle cleaning error, but no red screen error. Then I used the profile for "Fiberlogy FiberFlex 40D", which has the hotend at 220 °C and there was no error at z calibration and it printed successfully just the same as with the original Fiberlogy FiberFlex 40D filament, which I also have printed with before. So perhaps the nozzle temperature is important for this.
RE:
Hi,
Thank you for your reply.
I selected the Generic FLEX profile. It uses 230 / 50. I can get it to print if I lower the carriage enough for it to hit the bed before it decides to throw the red screen. For example, on a previous PLA print job that left the carriage around 100mm, change to FLEX, no way. If I lower the carriage to about 5mm send the print job, it will work.
Also, I have 2 MK4s printers, they do they exact same thing which led me to my conclusion even though I went through a ton of cleaning, resetting, and recalibrating on the first printer before I decided to try the second one. lol
For the record, when it does work, the print quality is really nice. MUCH better than when it was a MK3iS+ whatever.
Oh, I'm using obsidian .4 nozzle.
I'll try reslicing with one of the profiles you mention and see if there is a different.
RE: MK4s Loadcell Trips with TPU Loaded
I'm spitballing here, but maybe there is some resistance to the TPU being pulled off the spool as the extruder is moving down? I've had some TPUs that are a little sticky on the spool (especially if it got a bit too warm when drying it). Or maybe the TPU is dragging against something as it is being pulled down?
See my (limited) designs on:
Printables - https://www.printables.com/@Sembazuru
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RE: MK4s Loadcell Trips with TPU Loaded
This should be easy to check. When you load the filament and hit "Purge more" on the display, does the filament come out of the nozzle as usual or not?
RE: MK4s Loadcell Trips with TPU Loaded
I resliced using the "SainSmart TPU" filament profile. I screwed up and sent the job without moving the carriage up first so I didnt really get to check, but it seemed like it was better. Will try again on the next print job in 9 hours.
Purging filament is not a problem at all.
RE: MK4s Loadcell Trips with TPU Loaded
The problem that you describe that the extruder has to be at a certain height when you start a print is not normal behaviour of the printer. The height of the nozzle in z direction should not matter at all when you start a print. That is what homing is for. If that is not working, you should run a self-test on the printer.
And in my previous post I was recommending the profile "Fiberlogy FiberFlex 40D" for eSun TPU 95A, not the "SainSmart TPU" profile, as the latter gave me an error about nozzle cleaning. I printed two jobs yesterday with the "Fiberlogy FiberFlex 40D" profile and black eSun TPU 95A and both came out perfect.
RE: MK4s Loadcell Trips with TPU Loaded
Changing to "SainSmart TPU" filament profile seems to have fixed the problem!
I think there may be a bug in Generic FLEX profile.
Can you try printing with that profile and see what happens?
RE: MK4s Loadcell Trips with TPU Loaded
Which one do you mean? Generic FLEX or SainSmart TPU? I already wrote that the SainSmart profile did not work for me for eSun TPU 95A and the FiberFlex 40D profile was what I wanted for the prints that I did with it. I have printed SainSmart TPU 95A with the SainSmart TPU profile and it worked without a problem for the SainSmart filament, but not for the eSun TPU filament. I printed with an MK4S and the 0.4 mm standard (non-HF) brass nozzle in this case. I also have the ObXidian version, but in my experience there is no difference for "softer" materials. I am currently in the middle of a larger print project involving PLA and PCTG (for the first time), so I will not be able to try other stuff for a few days.
RE: MK4s Loadcell Trips with TPU Loaded
Hello, I was referring to the Generic FLEX profile. Slice something with it, load the filament, print. Don't actually need to print because the issue is homing.
RE: MK4s Loadcell Trips with TPU Loaded
Okay then. I printed a small TPU case foot with the Generic FLEX profile and eSun TPU 95A. Everything went smoothly and the same as with any other print job on this printer.
These are the settings in PrusaSlicer:
This is what the print looks like after printing on the build plate:
I have attached the project file to compare with your settings. If your printer has problems with homing, those must be specific to your printer.