Flow Rate and Pressure Advance Calibration Data on Multiple Filaments

I calibrated these filaments on the cool plate and the high temp plate, depending on the filament type. The purpose was just to see the variation across colors and brands.

Bambu X1C using automatic LIDAR calibrations first for Flow Rate and then for Pressure Advance using the calibrated flow rate.

Here are the results I got.

Wasn’t too surprised to see a big difference between FlashForge ASA and Polymaker ASA. But I was a little surprised on how much difference the color makes. Didn’t matter if it was eSUN, Polymaker, or Bambu.

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I would not trust these results unless you repeat it 3 times for each color, According to Bambu the auto calibration has 10% error from test to test , and from my testing i printed now over 300h on the X1C the autocalibration is good for nothing at best acceptable results. Use manual calibration with visual and caliper measurement i think Bambu studio allows that now, but i am using orca slicer. I did play with different colors and usually is very close result and stopped testing the colors for PLA and PETG and ABS, unless see issue or some special colors like silver and yellow. If dry and same print temp and same size nozzle and same manufacture, the same settings works, on ABS intentionally do a bit over extrusion and higher temperature for better layer adhesion, measured 0.97 and using 0.98

my esun eASA black and tested different ASA and ABS materials mostly

Manual esun black PETG

This is incorrect two different results from autocalibration for the same esun black PETG above

If you add a +/-10% to these numbers, you get some really outrageous values. The entire spread across the eSUN PLA+ color variation from min to max is 6% across my 15 samples.

But a gage R&R study is probably worth doing along with some manual calibrations.

Yeah good point, what i noticed that the flow can tolerate up to 1% change then is noticeable for ABS i am increasing it by 0.5% to 1% most times from measured to get better layer adhesion, For PETG i reduce it for some small prints by 0.5% , the K factor is a bit more forgiving for PLA 0.025 to 0.02 to 0.03 almost no difference especially at lower speeds which is around 8%. For ABS, ASA K factor difference 10% almost invisible for most prints.
In the Lidar auto flow calibration i am getting differences in the flow easy >5% same color/material the same you are getting which is a big problem especially for PETG look mostly and ABS less look, but layer adhesion problems and shrinkage percent changes . Still will print acceptable for most people

I did a manual flow rate calibration of the eSUN Peak Green since the automatic FRC had it as the lowest flow outlier. Turns out it 100% spot on. I was surprised – I thought the value would tend towards the rest of the results.


I was also surprised by the automatic calibration values.
@vladimir.minkov I repeated the test more than three times for some filaments.
I tried different plates, redried the filament, and even changed the name and brand of the material, as I was worried that the machine was memorising the values. In each case, the results were identical or with minor differences (the number of significant figures is higher than manual calibration). I was even more surprised as the values work.
I am unsure and still assessing the reason for such differences and the flow ratio colour dependence, but I am glad to read that I was not the only one.
I only had difficulties with a couple of filaments. I tested PLA, PLA-CF, PETG, ASA, ABS, TPU, PC from many brands, colours and properties (e.g. luminescent, transparent). I couldn’t extend the test to the abrasive ones (0.6mm nozzle not included in the automatic calibration).

@schmitzna I stored my values online just as a backup. But after seeing yours, I think an online database is more interesting; if you are interested, please PM me.

Although we are both getting very repeatable results on a single machine, a database would only be helpful if we quantified the machine-to-machine variation and found it to be a minor source of variation.

I have only one X1 so I cannot take that data.

I’d be happy to send you my spreadsheet if that would help.

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I only tried the dynamic flow calibration briefly and was left with a lot of questions.

  • I primarily use the 0.6 nozzle: what am I supped to do?
  • I generally use orca slicer, can I convert the K factors to the PA values in Orca?
  • The first filament I tried was TPU 'cause I can’t make sense out of what I get from the orca flow calibration but TPU is not supported by the automatic calibration (and the manual version didn’t show any useful difference from top to bottom).

This is from Orca Slicer the procedure is the same for any nozzle size
for TPU you may need to increase the test above 0.1 especially for 0.6mm nozzle
For all materials i use default test setting apart from TPU Where i use start from 0 end 0.2 and step 0.005 instead 0.002 but then the calculation of PA(K) changes K¶= 0.005xMesured best result height

In general K new values and PA is the same for Bambu and Orca Slicer tests
For Prusa there were two types of K¶ values , but after the latest FW upgrade, is using the same type . It is just two methods to calculate but i do not think you need to warry about it as K and PA are identical now . and mean the same K is the g-code command for PA
Use the PA tower method especially for TPU

You need both flow and PA(k) calibration for TPU or any other material



First chance to look at Flow Rate / Pressure Advance variation from spool to spool with same vendor, same color, and same X1C

eSUN PLA+ Cool White 0.949/0.026 on first spool, 0.955/0.028 on the second
eSUN PLA+ Silver 0.969/0.027 on first spool, 0.996/0.020 on the second.

This is interesting , i got variations for eSUN eASA black for flow 4%, but that was two different batches
Just curios did you dry both filaments before you do the calibration tests ?

From testing variations of flow +/-0.5%( some filaments up to 1%) and for PA variation +/-4% (most up to 5%) does not affect .
You are getting on the silver almost 3% on the flow and for PA 26%( really bad)
for the Cool white is not as bad for flow 0.63% and for PA 7% ( which is quite close just ok not ideal)

The new spools were right out of the package. The older, now used up spools were dried and kept in sealed containers with desiccants with hygrometers for less than three months.

New Right out of package is very often Wet. I just opened a new TPU 95 this morning and was wet.

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Didn’t even open this one yet. To be fair, I had it sitting on top of my dryer while two spools of ASA were drying at 75C. So the bottom of the spool and the desiccant package were probably warm and the plastic wrap on the top where the moisture condensed was cold.

Glad I have been drying everything I open before I use it after seeing this.