Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?  

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

Yes, thank you. I have seen the M104,  G code to turn off heating. It just doens't fail, it also then crashes along the bed, I'm not sure if the C1 saw this too.  I'm not letting Prusa ignore the problem, so I have to go along with the process.

RE:

UPDATE: 
Got my micrometer, measured the precision method cube walls in the print i mentioned earlier:
Could not be much more accurate (6 measurements on each of the four walls: 0.451 average with 0.001 standard deviation)! 
So no adjustment needed for extrusion multiplier (it would be 0.9978, not sure what resolution is for that field, but that seems close enough to 1 for me!).

I did this time do a thorough water+dish-soap ONLY cleaning.

Next print was a single layer calibration layer:
Calibration Strip for simple Live Z/First Layer calibration
I printed the large one. Profile was using z=-0.04 still: I assume the live adjustments are on top of this???
Maybe I wasn't using big enough steps?
Anyways, results in photos below: not sure how to interpret, and in any event no obvious problem.
So NEXT I just tried again to print that benchy: same problem! (Although it seemed to print a couple more layers than the first three tries before adhesion failure, when the thing started to get moved around by continued printing).

So what next??? Ruebarb: I could try turning off fan, although seems very odd that would be required.
I do have the advanced filtration installed.
So HOW does one go about disabling the fan?
And preventing the printer from automatically opening the vent???

Live Z Test Results

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

If this is your bottom layer then it is definitely too high, so maybe detection if the bed jas some problems due to the filament buildup on the nozzle? I know that since introduction of the load cell in MK4/CoreOne it is extremely important to have a clean nozzle during bed calibration - which is especially annoying with the PETG which tends to ooze out.

Some people updated their start gcode to preheat the nozzle to the lower temps so that PETG is not oozing out,  then do bed calibration and then bump the nozzle temp higher.

Another option is to adjust z offset so that the first layer it more squished.

RE:

Interesting that you closed the vents. I have experimented with bumping first layer bed temp to 90c and chamber temp to 40c with vents 2/3 closed when fighting a warping print on the textured sheet. I did not think you would need that for a benchy but maybe it is worth trying.

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

This is a case where you can benefit from a nozzle wiper mod. I've seen in the past 1st layer issues caused by an uneven bed mesh probe, which in turn was caused by melted plastic accumulating on the nozzle.

RE:

I recommend using the Live Z file I posted, 5min file. There are many ways to make this adjustment, this is how I do it.

Do not proceed to next, unless yes, otherwise repeat with lower offset. Making adjsutments, don't bother with a 3rd digits, beyond .005, just start with 0.01, 0.02, 0.03...

• Print in one piece
• Remove in one piece
• Review the 5 squares,
  • Front, uniform appearance, all the layers attached
  • Backside, good appearance, layers hard to see, all blended
• Lastly hold the entire thing up to a light and look for any holes, even tiny ones,  you'll see the light come through. 

RE:

Since I've been chasing Nozzle cleaning issue, which at this point appears software releated and not hardware, in my instance.  I've done alot of testing with this filament on 3 nozzles.

Here is what I have if it is helpful to you. The file attached has all the filament settings and printer settings, turn off fan, g code....

Diamondback

• Galaxy PETG Filament
  • Ext Multi 0.98
  • Temp 240
• Printer Profile
  • Z Offset -0.02
  • Elephants Foot: 0.5

HF

• Galaxy PETG Filament
  • Ext Multi 1.0
  • Temp 250
• Printer Profile
  • Z Offset -0.02
  • Elephants Foot: 0.5

Hardened

• Galaxy PETG Filament
  • Ext Multi 1.0
  • Temp 250
• Printer Profile
  • Z Offset -0.01
  • Elephants Foot: 0.5

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

OK below is a significant update (based on printing done before the last few posts above had been made). I will thank everyone for the ideas so far, and appreciate the info and live z file above Ruebarb!

And can anyone share a link to a good wiper mode for core one L? I don't even know if that is just a part to add or if it also means added gcode (can you do that?).In other words, would need a link to something suitable for a newbie.

THE UPDATE: Although my 5th print also failed when I tried a larger Z offset (-0.058), I noticed it got twice as far as all the other failures.

So next I tried with Z offset of -0.06 (I know: just very slightly more than above attempt), BUT IT WORKED - Benchy cam out nice: see photo below. That was Monday. Then I tried the same again Tuesday to be sure: 2nd one came out just as nice (no photos of that one).

OK, now to try something practical - here is the printables.com link: "Samsung Galaxy Tab A9+ Wall-Mount Case - home assistant use"
Base part printed fine: see photo below.

But the top part, which is admittedly more challenging, has failed twice in a row: photo below.

I am wondering on next steps to remedy the top part failure: I will wait to see ideas here, but my first thought was to clean the plate again and bump Z offset down another .002 to -0.062.(Since it was a very small Z update that allowed the Benchy to go from failed print to good print!)

Thoughts?

3D BENCHY SUCCESS

BASE PLATE OK

TWO FAILED TOP PARTS

RE:

Just wanted to add this about the failed top part for that Samsung tablet mount:
It seems like the model is trying to print it the wrong way (upside down).
The more I look at the model, I am wondering how it can work.
Below is what the slicer shows AFTER I flip that part upside down in the model:
shouldn't I be printing it like it is shown below, where I've flipped it?

EDIT: Just not sure with a 3D printer how much of an open-air overhanging surface you can have!?

Failed Part Model, Flipped Upside Down

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

Sometimes models are placed differently for getting specific print quality, such as top layer. Personally I would keep it with the wider area downwards. Otherwise you want to enable brim to improve adhesion

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

Posted by: @_kaszpir_

Sometimes models are placed differently for getting specific print quality, such as top layer. Personally I would keep it with the wider area downwards. Otherwise you want to enable brim to improve adhesion

Thanks - That makes sense to me, thanks for confirming.
I will try it flipped tomorrow (barring any other more interesting ideas in the meantime!).

RE:

My experience with the textured sheet at this time and Prusa PETG, is that they are not a great combo. I have been able to improve adhesion, but ultimately through all testing, it is not possible to get 100% reliable bed adhesion & no warmping for all types of prints. I have gone to the Satin sheet, 100% success so far. I'll come back to the textured sheet when I go back to Sunlu PETG, which is sticky.  The reason for the textured sheet was for using the texture as the face of the part for what I am printing and also we didn't have satin sheet back in the day, the top layer finish quality of the Galaxy PETG is amazingly better than the textured sheet. So for Galaxy PETG I will make prints face up.

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

OK, before I tried any of your other ideas, for the failed Samsung table frame top part, I tried to print the design after flipping it upside down in the slicer.

The result is below: can  anyone advise from the appearance what the issue could be and how to fix this particular issue?

(Reminder: the Samsung tablet frame design is from printables.com, located here.)

Top Frame Reprint after Flipping Upside Down in Slicer

RE:

This looks like a layer separation/delamination. The filament starts to shrink when cooled - the shrinking tension generates a force that pulls the filament and if the binding to the previous layers is too weak then it will start to rip away whole lines from the previously layed layers.

Some suggested fixes:

- bump nozzle temperature for about 10C, for example 250C is standard now on fast printers

- slow down the print speed to for example 50%, can be done while printing using a Tune in the menu

If that does not help then we can suggest other things to check, but usually those are adjustments for fine tuning the print settings for the specific filament brands:

- use Prusament preset as a base for the given filament - so if younhave some PETG then try using Prusament PETG profile

- increase cooling and set the fan to 100% except the first layer

- increase extrusion percentage a bit or increase the perimeter overlaps to increase layer bonding....

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

Posted by: @_kaszpir_

This looks like a layer separation/delamination. The filament starts to shrink when cooled - the shrinking tension generates a force that pulls the filament and if the binding to the previous layers is too weak then it will start to rip away whole lines from the previously layed layers.

Some suggested fixes:

- bump nozzle temperature for about 10C, for example 250C is standard now on fast printers

- slow down the print speed to for example 50%, can be done while printing using a Tune in the menu

Thanks! I will try those first two points first to see if it helps, stay tuned.

RE:

Open this 3mf, drop your file on the build plate, turn off supports if not needed and hit print. If you don't see any improvement with this, then you have other issues. The printer is called HF Satin C1l, works with textured plate also.

RE: Failed First Print - Fix for PETG Benchy that shifted after a couple layers on textured sheet?

Use this one instead, extrusion wasn't corrected for the HF nozzle.