Not sure why this keeps happening but I keep getting gaps on my bottom and top layers. My flow calibration looks really good but when I use .98 it has gaps. Ive already upped my flow to 1 on a real print and I still have gaps. Not only that the top layers are rough. What else can I do? Bambu told me to do a flow rate calibration but I’ve already have with undesirable results.
Overture pla, generic profile default everything
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These teeth marks on your patch are a sign of over-extrusion.
The gaps in the top layer a sign of under-extrusion…
I assume you did the k-factor calibration as well ?
Print the standard cube after scaling to just 3mm high.
2 or 3 bottom layers 4 top layers, infill to your liking…
Crank the infill overlap down to 10%.
IF the flow ratio is good there should be no teeth marks on the top.
If they are still present then lower the flow rate in tiny steps until these teeth disappear.
You can still feel them but they should be visible to the naked eye.
Assuming after a few prints it comes out fine try with those setting on a larger cube, like 50 by 75mm - 3mm tall will do but observe how the top layers print.
Your surface looks a bit rough and it might help to increase the nozzle temp by 5 or 8 degrees.
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I just let the flow rate compensation do its thing, not sure how it works really. Ive calibrated manually but i get a flow of 1 and a k in the range of .30-.34 which seems really high for regular pla. Its only rough at a flow of 1 but im still underextruding at 1.
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The k-factor can only be properly done AFTER the flow rate is honed in.
Do it the other way around and you fix one issue by making another one far worse 
I try to explain:
If your flow ratio is too low than the k-factor that looks good will be WAY off target because the filament has to fill the gaps caused by under-extrusion.
Same story the other way around…
Flow rate too high and you get impossibly low k-factors, resulting in gaps and bad seams, plus more.
The cube test makes sure the flow ratio is calibrated to produce a solid, gap free infill on the top that also has no signs of over-extrusion.
Since you k-factor might be way off set it the default 0.02 to get going.
Once the flow ration prudes a perfect op calibrate the k-factor and Bob’s your aunty.
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Ive done it in studio and orca and i get the same range no matter what way its done
None of those patches look acceptable to me…
Something is off…
Where the infill is smooth there is still those teeth on the walls.
And they are in all patches…
Let me print a simple 30 by 30 with plain defaults for comparison…
Will be back…
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Ive used studio and orca to calibrate. Looks identical, im using the .4 hardened nozzle (set in printer parts) and using overture and sunlu pla. All comes out this way. Thanks for the help, been trying to figure this out since the 19th. When i run orca i make sure to turn off flow dynamics as well. In orca i just hit the pass 1 under calibration under the top. To add ive taken apart the heat stone and tightened the screws too per the wiki.
That’s with just the default 0.2mm profile and white PLA…
30 by 30mm and 3mm high.
The calipers were placed flat right on the edge where those teeth are…
Here’s a video of the last bit of the print to give an idea of the print speeds.
No ironing or such, just the defaults and well calibrated filament…
last bit of the print…
Looks really good but its an entirely different machine. Im using the a1. P1s or x1c doesnt have flow rate compensation, thats where im getting confused. Its marketed to not have this issue but here I am…
My P1 does not have a flow rate compensation either, just the k-factor setting for the filament.
And the A1 has the same, k-factor and flow rate…
One of my previous printers was a dual head running only on the provided slicer and there was only a flow rate adjustment, no k-factor, no flow rate compensation and top speed was about 60mm/s - still my top surfaces looked like this…
Out of the box my P1 produces quality prints on par with your images
If you have flow rate compensation turn it off and calibrate
Its been turned off and left on while calibrating in orca. You cant turn it off or on in studio. Idk why these bambu printers are so confusing. My enders worked flawlessly. I sent back my x1 and sold my p1s. Nothing but issues, I waste more filament calibrating then actually print. Ive already used a quarter of this roll of grey and im still getting nowhere.
Flow compensation should manually adjust my flow per the eddy sensor. Doesnt look like that happens here automatically or is there any change of me doing the calibrations myself.
Like you said these calibration squares arent acceptable so I cant even get past the first step to fix whatever issue this. How does it underextrude and overextrude at the same time within bambus own calibration? Even using orca im getting extreme values. Support has me running in circles, i do what they say, send proof with pictures and videos just for them to tell me do the exact same thing ive already done countless times already. This hobby is really starting to be lame.
I think we are running in a circle here as either I was not clear or you misunderstood me…
Let me try again from scratch…
I ASSUME your goal is to get this filament working as advertised.
I also assume that you are not shy of wasting a little bit more…
Less than 3g per cube…
Set all filament and print setting related things to their defaults.
For PLA use a print temp of 220 degrees Celsius for the start.
Resize the standard cube to 3mm thickness.
Print it using all defaults and mark it for later comparison.
Now pick the cylinder or cube again but in vase mode and about 5 to 8cm tall.
Set the outer wall thickness to 0.6mm.
MEASURE with callipers how thick the resulting wall of the print is.
The calculate the required flow ratio to match the 0.6mm.
E.g.: If the wall is measured at 0.52mm while the flow ratio is at the default 0.98:
0.98 divided by 0.52, then multiplies by 0.6.
Gives a flow ratio of 1.13 - roughly.
This value however ONLY works for single extrusion lines.
But this value is most noteable in order to do vase mode prints or thin walled objects.
Print the 3mm cube again with these flow ratio settings and if you had to increase them you should see clear signs of over-extrusion.
THAT IS NORMAL AND EXPECTED.
Now for the fun part…
You have two test subjects to compare…
They should give you a clear indication to the direction of the flow ratio…
Let’s say 0.98 looks half decent and the vase mode result totally over-extruded.
Lower the flow ratio until you see fine gaps between the lines - note the previous value.
Now to it again the other way until you start to see signs of over-extrusion - note the previous value.
The two values you now have are your goldy-zone.
The middle should work fine…
If you want even better results create a 3mm thick model with a long but slim stretch, a circular patch on one end and a square on the other.
The stretch should be only wide enough to result in short infill lines.
Turn the flow ration down until both the stretch and the two patches come out with even quality.
After the flow ration is done do the k-factor calibration and you print should come out as it should.
Those test patches are great - if you know how to use them and the results are consistent, which they are not in your pics.
I know it sounds like a lot of work but can done in less than an hour and the same filament with a different colour some manufacturer) should work close enough with these settings.
To calibrate a new roll you only have to make minor adjustments if any.
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