Inner wall marks outer wall and VFA

[Snow]

Hi! I had a few quality issues. First I found was issues with overhangs, that I slightly improved tensioning belts following your wiki instructions until achieve good overhangs up to 65º. Second one and my headache here is issues with inner walls marking outer walls and some VFA (attached in photos). I made tensioning and cleaning multiple times calibrating before and after doing hardware tesioning/cleaning/relocation, changed all wall generation parameters I could suspect to be the issue (line width on walls, wall generator classic to arachne, wall loops, disable thin walls, inner to outer to inner…), and put printer on the floor suspecting this could be due to vibrations on the table, but still having same issues. Sharing photos and 3mf. Could be an issue of the printer? Anyone of you had same issues? (all this test was with both testing filament that comes with printer, and my own eSun filament, and with standard preset of P1S and tuned preset)

My procedure for belt tension: loose 4 screws of belts with Y gantry pushed to the end, move carriage in Y axis for 3min going to start-end of Y axis, back again to end Y axis and screw again. (also followed this comment Print Quality Issue, Overhangs, X1 Carbon, PLA - #20 by ceaddl without success).

[Olias]

It sounds like you may have some experience with other printers prior to Bambu where one has had to tinker with every mechanical setting. I can say this, that’s a waste of time with Bambu unless there is a mechanical defect that shows up during filament calibration. If you’ve printed a Benchy and it looks fine, then your problem is likely not mechanical.

Based on your photos and your comments, I would wager that the problem is more likley with the model than with the appliance.

If I can judge by zooming in on your model, I would estimate that your wall thickness is only two layers deep. If that is true, it would be expected to produce the shadowing affect that you are experiencing. Essentially what is happening is that as the filament is shrinking on one side, there isn’t enough material thickness to counteract this.

Now you might try two things to remedy this. First, increase the wall thickness, although if your walls are already too thin, that likely won’t affect it.

Secondly, you could try slowing down the print by printing it in silent mode which will reduce all movements by 50%. This is only available after the print commences. It is available on both the control panel and inside the slicer. Mind you, it is tricky, you have to be patient as that setting only “Sticks” after the bed leveling is done and the print head starts moving. Even then, it can take a layer change mid-print to take affect so you have to watch it and ensure that the selecting stuck. It’s either a bug or bad design.

Two lesser alternatives would be you might also try increasing the fan speed to cool the filament faster but I highly doubt this will help but try it anyway. The other alternative is to change the wall order from the default of inner/outer to outer inner. Again, I doubt these will help.

The best solution is if you have access to the raw model, redesign the wall thickness.

And last troubleshooting tip. Using the cut tool, isolate a section of the model that can reproduce these errors so that you can quickly print smaller test subjects that print faster and use less filament thus allowing for quick experimentation.

[Snow]

Hi! First of all thank you for taking your time to reply

Already tried that changes (surprisingly silent mode makes it even worse), and it happens with another models, but in that model issues are more easy to see, even in standard calibration appears VFA on back side. Indeed I didnt try the default benchy, gonna try, thats will be a clear point to see where is the issue. Gonna try when I arrive at home and post an update.

(Sorry for my bad english)

Edit: also I created a ticket, waiting for some clues from Bambu Lab

-Frank

[Snow]

Default benchy gcode, fresh Bambu Lab PLA basic, opened doors, standard speed. Good overall, but has brightness issue and that mark in outer wall due to inner wall.

[Olias]

That change in texture is most often associated with a change in speed. In this case, this is exactly where the deck of the bench is.

This would be an indicator that your filament profile is not optimally tuned. If you’re not using Orca, I suggest you download it and try it. Use their Max volumetric flow utility to optimize flow. Click on the Tutorial option for tips on how to use that feature if you’re unsure.

Or you could trial and error your way by optimizing it by hand in the speed submenu but that is very difficult and so far I’ve had little success in getting great results.

Or last but not least, just set the printer to “silent mode” during print which will slow down all movements by 50%. That is probably the quickest way to verify that it is a filament profile issue but it will come at a cost of taking twice as long to print a model. But you can just set it and forget it and come back later as opposed to tinkering with settings at first.

[Snow]

Benchy gcode use to have that brightness issue due to accelerations were set when sliced (checked some videos about this default benchy, and all of them have same issue). After testing a lot (maybe too much) posibilities and even testing with software downgrades, I give up and will just wait to bambu lab to response the ticket.

[vladimir.minkov]

@Snow , i have been using the my printer X1C for over one year with no issues apart from the ones i had , but lately started small VFA ringing it is still tiny and almost invisible and is not related to bench as my bench is around 40KG rock solid literally on top of the bench and the VFA started showing lately
Hope support come back but they have been unreliable , please share what they come back

But started looking into forums and etc , and apparently belt tensions , belt aliment , in general alignments will cause that . Apart from lubing the last time i did belt tension and alignment was probably around 10Months ago

Please share which was the main reason for you , as soon have to go through the pain of fixing it again as slowly but surely the VFA starts to become more obvious even at slower speeds

For my other printer i had some VFAs and the vertical rods were not perfectly aligned and one of the belts was not aligned and the tension was wrong and that fixed it . But that is bed slinger and much easier to work on or may be we took it apart one too many times over the time and have build up some experience

[Snow]

I guess that tomorrow I will have some response (I hope so), as soon as have some news, I will notice you. Also I asked to a professional team that use to works with a lot of machines, looking for some experience like this.

[Snow]

Hi again. A few news, Bambu Lab asked me to do some hardware checks, cleaning and tensioning, and print a 3mf test made by themselves. Still having same issues, waiting for more responses. The response by professional team I mentioned, they suggested me to do some changes in my settings but didn’t work for me, waiting for more responses too. I will stay you informed of some another news.

[Snow]

Hi! Still waiting for responses from Bambu Lab ticket (Bambu Lab support it’s just a shame, is unacceptable wait 1 week for 1 response in a issue ticket on a recent order). I opened the P1S case trying to align all belts to the center of the idler and greased them (top, bottom and rear, never teeth), and VFA seems better now (not perfect, I think it could help buy new belts). In order to inner wall showing in outer wall I still working on it, I gave up and continued printing pieces for my projects, btw printing some pieces yesterday I looked that my k-factor could be tunned better, so in a few days I will test in again. If I have any news, I will notice you.

[MalcTheOracle]

I’m three weeks into a ticket with zero response.