Any ideas what could cause this?
Bambu P1P using Bambu PETG with all system preset settings… Bambu PETG Basic and 0.20mm Standard @BBL P1P.
Low humidity in room (30% RH)
Showing only to the right of embossed areas. Very smooth and glossy otherwise.
Most likely culprit is poorly calibrated filament profile. Don’t trust the default profiles as Bambu PETGs as well as others often are inconsistent in the formula. I’d take a close look at flow advance as the first area I’d calibrate. the best calibration tool can be found in Orca Slicer if you aren’t already using it.
Although PA tower is more advanced and will produce a more accurate calibration, it does require understanding of how to use the tool and it takes up to 25 minutes to run. I therefore recommend PA Pattern as a quicker method that should be good enough unless you still find the filament uncooperative.
Click here for help tips.
- Help Video 1 on how to use Orca
- Help video 2 that starts at 10:11 and discusses the use of the PA Pattern test
- Orca Slicer calibration tutorial
If you wouldn’t mind though. Please print a calibration cube first and upload a picture. Although any calibration cube will do. The Voron Cube has a series of lined patterns that really punish poor pressure advance calibrations thus making it a good test model.
By uploading pictures of that model, we can then have a reproducible model to compare your results to and give a better answer.
Note the three model examples here. The one on the left is a well-dialed-in Bambu PETG whereas the ones on the right are two experiments with the same PLA that I experimented with using a Bambu Default profile(B) and a fully calibrated profile(J). Calibration can make a big difference.
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Thanks so much for your reply Olias! I ran out of the blue filament, and am waiting on Amazon to deliver. I will definitely run the calibration! Would it be a safe assumption that “well established” filament makers adhere to reasonable QC standards? Therefore eliminating the need for calibration for every roll… or just calibrate when switching to another manufacturer?
As soon as I get the new batch (a few days) I’ll run the calibration and post some pics!
That… my friend… would be an unsafe assumption. 
I’ve had both good and bad experiences with filament. If you see some of my earlier posts, I buy on price-only and have posted proof of filaments that have wildly different pricing but obviously come out of the same factory. Among the poorest at quality control has been Bambu of late. I’ve criticize their Silk and Matte PLAs as being very inferior to the competition but at the same time they charge a 60% premium and have bad shipping and return policies.
Since you’re an Amazon customer, hopefully you are also a Prime member. Here’s an open secret I’ve shared here before… Amazon will take back any filament you are not satisfied with even if you’ve used a portion. I would say 10% of my first-time filaments are returned and checked off on my crude spreadsheet as “Blacklisted” while others have been great quality albeit inconsistent pricing. My quest is for the $10 spool which I have hit from time to time but not with any consistency.
Here is a couple of threads on that topic.
That… my friend… would be an unsafe assumption.
I’ve had both good and bad experiences with filament. If you see some of my earlier posts, I buy on price-only and have posted proof of filaments that have wildly different pricing but obviously come out of the same factory. Among the poorest at quality control has been Bambu of late. I’ve criticize their Silk and Matte PLAs as being very inferior to the competition but at the same time they charge a 60% premium and have bad shipping and return policies.
Since you’re an Amazon customer, hopefully you are also a Prime member. Here’s an open secret I’ve shared here before… Amazon will take back any filament you are not satisfied with even if you’ve used a portion. I would say 10% of my first-time filaments are returned and checked off on my crude spreadsheet as “Blacklisted” while others have been great quality albeit inconsistent pricing. My quest is for the $10 spool which I have hit from time to time but not with any consistency.
This is an example of a dirty plate that was deliberately touched with fingers although the textured build plate “looked” clean.
Here is an example of a smooth plate that shows finger prints more readily. You can see the fingerprints interfere with first layer adhesion.
Yes… I’m a Prime member! Used MANY returns, but no filament yet. Great suggestion and thanks for the tip!
Looking in Orca slicer for the Voron Cube model… any pointers where to find it?? 
Not sure what I’m looking for here? I’m guessing somewhere between 0 and +5 give the smoothest center area. Above that the edge gets very rough and “toothy”. 0 is starting to appear “thin” (a lighter shade) in the center. The negative numbers all appear to get thinner or lighter still.
P.S. I downloaded the cube from Printables… printing now.
I think those two pics should be stickied at the top of every printers sub categories.
That is the clearest example of why the plate must be cleaned and what happens when it’s not.
I’ll let you in on two tricks here.
- Don’t rely on the naked eyeball for smoothness test. Instead, close your eyes and rub the blocks with the back of your fingernail and listen to the raspiness. The one with the smoothest feel/noise is the best.
- If you do want to perform a visual test, let’s say like on a PA Pattern, a great trick I learned is to use your camera and use the macro mode to do a closeup. You will see a whole lot of greater detail that the naked eye cannot see.
If you want to have a useful tool that also helps. I’ve got a number of jewelers loupes but this one on Amazon is probably the best at doing inspections. It is meant for stamp collectors but works really well on flat prints too.
There are a dozen companies that make these and they are all the same, so buy on price. Just do a search for this image.
https://www.amazon.com/s?k=Handheld+Magnifier+Loupe+with+Measure+Scale
I’m retired from 40 years in the printing industry, so I’m used to looking at small details… registration marks, etc. I have several loupes I’ve collected over the years. I considered shooting pics with a magnifier app on my phone, but it still only showed a crosshatch pattern similar to the basic 1:1 camera. Thanks for the “fingernail tip”… and based on that scratch test, the +5 wins.
So looking at the cube… where to go from here?
I don’t want to pile on until you get the new extruder in place because there are too many issues which may be fixed with the new extruder and lets hope that’s all there is. But to cite just two of the cube faces and areas he needs to focus on once he gets his machine back into shape are here:
Contrast that with this PETG cube I showed above.
And please note that even that shape is not perfect. I tried to capture an angle and lighting in this photo to show the banding I have not been able to calibrate out.
The point here is that it is that calibration in my experience is a compromise. I’ve never been able to achieve absolute perfection on every aspect. The grey cube BTW is Bambu’s new PETG-HF, admittedly one of their best filaments I’ve used and I think I’ve gone on record enough times stating how inferior I consider their other filaments. The PETG-HF is a winner.
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Pick the sample with the largest, smoothest, central section. The edges and borders do not matter for these flow calibrations - that is mainly corrected by adjusting pressure advance (aka K value or dynamic flow).
I’ve done the Flow Rate and Flow Dynamics calibrations. I also believe I had the nozzle temp too high… I remember a while back cranking that up a little trying to achieve a more consistent gloss, not realizing (until now) the other issues that could cause.
I’ve lowered the nozzle from 260 to 245. But now realizing I maybe should have lowered the temperature FIRST before calibrations??
Incidentally, I’m using Creality PETG. I’ve also lowered the speed quite a bit…
Initial layer = 50 mm/s
Outer wall = 50 mm/s
Inner wall = 60 mm/s
Another cube presently printing… will post results.
Well, yes, that would be the logical choice. If your temperature is too far off then it will affect your calibrations. Some of the items seen in this areas as an example can be attributed to incorrect temps.
I tried various iterations… lowering the temperature each time. Very little change in sag in overhangs. So… after chasing this down a literal rabbit hole, I reverted back to my original settings and drastically slowed the print speed, especially on overhangs. This produced an acceptable result, although not perfect.
Outer wall = 40
Inner wall = 60
Overhang = 50 / 30 / 10
Small perimeters = 40%
I’ve heard some good things about PCTG as a PETG replacement in drastically improving sagging. So… taking a deep dive into investigating switching filaments.