Material buildup at edges (direction reversals)  

RE: Material buildup at edges (direction reversals)

Do other slicers do the same thing with the same settings? Posting your settings would help. However, it might not be a slicer issue. Printer settings like speed, jerk, acceleration, temp. It is more pronounced on shorter runs, so i am thinking acceleration and jerk settings in the software. You might want to post those also.

RE: Material buildup at edges (direction reversals)

I only use PrusaSlicer, and I am running the current version 2.9.4.  I am running FW 6.2.6 because of known issues with 6.4.0.  I am using the Prusa 0.2mm SPEED profile with a 0.4mm nozzle.  I have not tweaked any speed, jerk or accel settings.

I played around with the Pressure Advance last night.  When I set it very high (0.100), the buildup was significantly improved, but now I see pin holes around the junction of the inner perimiter and the infill.

I had previously run the Pressure Advance Calibration (the one that generates gcode of parallel lines with speed changes) and it looked like 0.055 was the best choice.  That is the setting I had used to generate the print in the original picture.

RE:

To me, this looks like overextrusion.

I'd try to calibrate the extrusion multiplier as described in this Prusa help article:

https://help.prusa3d.com/article/extrusion-multiplier-calibration_2257

RE: Material buildup at edges (direction reversals)

@jgeiger2024

I 100% agree with @lw36, once calculated you may adjust your volumetric flow rate, and if done correctly for the specific filament your using, you should see a great improvement. Also this is the key to great seams, although there is more to that. 

Note: that I mentioned the specific filament, this can be different for all filaments. (No one size fits all)

I would simply have "liked" @lw36 suggestion. However the Prusa forums has removed the impotence that a persons reputation has here, by taking the names away from the liked area and only allowing the number of likes, as well as banning those that have shown information that is not desired by them. some people are "waaay" more knowledgeable then Other's, Prusa has gone out of their way to try and remove this from the community further diluting there worth. But all they care about is their bottom line $$$, They are a corp that uses the community to make money, so it's what we have to deal with instead of just being able to like someones suggestion. Just mentioning, this is a manipulation that I hope people recognize. It should also be noted since I'm forced to do this, since I can't just "like" someones comment and have you understand that I'm extremely knowledgeable, and agree with the poster referenced, that simply making many posts here does not make you more able or intelligent, however the way Prusa assigns labels like "Honorable Member" and "Illustrious Member" would appear to imply this.

Do not be fooled by this! look at what is real, their are persons here that are legit, however not everyone here with the designation of "Honorable" or "Illustrious"are what they attempt to be, so watch carefully (pay attention). 

If your intelligent you will see the truth.

RE: Material buildup at edges (direction reversals)

I have recalibrated the extrusion multiplier and the pressure advance. The results are slightly better, but still not what I would expect. I have attached the 3mf file I am using.

RE: Material buildup at edges (direction reversals)

Trying again to attach the print file

RE: Material buildup at edges (direction reversals)

Third time is a charm??  Not sure why I cannot see my attachment (Flat_Star.3mf)

RE:

Known issue of these forums for those of us who have been around the block a few times. This forum will silently remove any "unapproved" attached filetypes, and unfortunately for this audience .3mf is one of the unapproved. Zip it up and post the resulting .zip file.

RE: Material buildup at edges (direction reversals)

I have recalibrated the extrusion multiplier and the pressure advance. The results are slightly better, but still not what I would expect. I have attached a zipped copy of the 3mf file I am using.

RE: Material buildup at edges (direction reversals)

Has anyone tried printing my file to see if your results are similar?

RE: Material buildup at edges (direction reversals)

Just a quick FYI, always best to zip .3mf files as those ones tend to upload with the least amount of issues. 

RE: Material buildup at edges (direction reversals)

You changed the filament diameter from 1.75mm to 1.72mm but left the extrusion multiplier at 1.00.

Did you maybe adjust the wrong field? This would lead to the inverse result (lower diameter -> more filament must be extruded to get the same volume -> Overextrusion)

When printing with your settings, I too see some overextrusion, with generic PLA settings, it prints perfect (MK4S with HF nozzle)

RE: Material buildup at edges (direction reversals)

When I had started my repeat tuning, my multiplier was 0.95.  I kept that as a starting point but changed the filament to .172 after measuring it.  I then performed extrusion calibration and came back to 1.0 after measuring the calibration cube wall thicknesses (vase mode).  The wall thickness was 0.042 instead of 0.045, s0 roughly 7 percent under extruded.  The calculated multiplier would have been 1.017, but I chose 1.0 as my next test.  This should have resulted in slight under extrusion of the star, but the results appeared to still show over-extrusion.

scratching my head…

RE: Material buildup at edges (direction reversals)

Anyone have any other ideas or have experienced similar issues?

RE: Material buildup at edges (direction reversals)

The only idea I have left is to try printing it with the Generic PLA setting and unmodified Print(er) settings.

Atleast I already "miscalibrated" filaments and the easiest is to just start fresh.

If you have other filament, maybe also print the model with that to determine if the issue is the filament or the printer.

Thats all I have, sorry