Had I known the printer would be like this, I could have just bought the P1P and saved a lot of money.
Donāt dismiss the Lidar. I found that it has vastly improved over time. I use it mostly for determining PA factor, because it seems to be more consistent than all three of the tests in Orca. Of course it could also be my inability to interpret the test results 
But I tried all three tests and the Lidar result usually gives the best corners.
If I print a material that I havenāt calibrated yet, it is great to still have PA at hand.
And it seems that it can now handle the structured plate as well.
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I found manual calibration is better than the lidar calibrationā¦ The lidar auto calibration always fails for some reason too, so I just stopped using it.
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When did you try last time?
Just to be clear, by ālidar auto calibrationā, are we referring to the one that can be enabled to happen just prior to the print occurring, but which never tells you what it measured, or 2. the one in orca slicer where you have the choice between manual (you do it) or automatic, where the slicer does it and reports the pa result for you to enter into your filament profile? In theory they should arrive at the same number, butā¦ maybe itās actually different code that does it depending on where it was invoked? Iām probably overthinking it, but itās not obvious how to confirm if the first way never tells you. Then again, maybe itās written in a log somewhere.
Couple months ago maybe? I really dont remember. I put the engineering/cool plate in and tried to calibrate some filament and it kept saying it failed. I cant remember if it failed on the the flow dynamics or the flow rate calibration, but it did over and over with several different filaments.
For the cost of the hardware that Bambu used, itās actually a really impressive feature. The problem is it only works in certain conditions, and unless youāre looking at log data every 5 seconds, thereās no way to tell when it has failed to determine an optimal PA value.
And that is in part due to the way the calibration sequence works. It prints several lines with varied flow conditions and then images those lines to make sort of depth maps. It tests a fixed number of exposures, and if it canāt find an exposure setting that lets it image anything clearly, it gives up and tells the printer to use a PA of 0.02.
It also does not work well for nylon or TPU, I guess because of the differences in reflectivity of those materials
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The lidar and camera is used when it calibrates the flow rate and the pressure advance in the auto calibration section in BambuStudio.
Since it already uses the camera and the lidar to measure the width of the filament path, it should be possible to measure a print and compare that dat data to the current position of the toolhead. Iām not a software engineer, so I dont know what all it would take to do that, but I assume it would be possible based on how the lidar and camera is already being usedā¦ If they cant give us that, they should give us more options in the slicer to combat the inaccuracies.
Ah yes, that one. The orca slicer one is manual mode only.
Itās easy enough to test. Iāll print out the pass 2 flow rate calibration pattern using what I last manually calibrated to. Then Iāll get the number that the auto lidar recommends, use that number and print the same pattern. Then compare. If it photographs well enough, Iāll post the results here. Same for PA.
I did a comparison to OrcaSlicer printed on different machine as well:
While the Bambu X1C Prints pretty nice, it is really far off from 20mm in my opinion. This is fully auto calibrated filament too, which made no difference in size (I tested before and after to confirm)ā¦ If anything, it made it worse as you can see some slight ghosting in the inner square.
My CoreXY doesnāt print as beautiful as the X1C, but I can print accurate at roughly the same speed which is more important for meā¦ I can get it even closer to 20mm if I want, but this is close enough for my testing. the 98.5% shrinkage compensation is set for the filament where I never have to manually adjust models in the future.
If you used shrinkage compensation for the X1C, do you not get the same result?
19.68Ć·20
=0.984
His post sound like he used the shrinkage compensation for the other printer, but no shrinkage compensation for the X1C.
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Yes thatās a great point. Rate of heat transfer differs by hotend type, by manufacturer, and of course slicer settings. This alone is an astounding number of variables that are hard to test unless you own multiple devices that are each calibrated and ready to print.
I honestly havent used OrcaSlicer with my X1C in a long timeā¦ I got tired of going back and forth as updates and improvements came out with BambuStudio so I just stuck with it since they released the auto calibrationā¦ When I get more time, I can try to adjusting the old profile I had in OrcaSlicer and try a test.
So in the two images above, you have applied shrinkage compensation to the Klipper device but not the Bambu? Also Iāve noticed Orca does some weird stuff with movement commands compared to Bambu Studio, so it may be best practice to use the same slicer for comparisons (easy for me to sit here and complain about, just thought it was worth noting since Orca and Bambu Studio do have their differences)
I have done hundreds of tests between my printers, I just dont share them all on here. The pictures you saw, I printed out around 25 test prints per machine with many different settings in this one test alone. My CoreXY settings and print time is almost identical to the X1C, but none of that matters since they are completely different hardware.
The main focus in my results is that OrcaSlicer allows a setting that will automatically adjust the model to compensate for filament shrinkage where as BambuStudio will not.
You can still use Bambu Studio, the only annoying thing is that you have to remember to set it every print because you canāt save it to the filament profile like in Orca. I donāt understand why Bambu hasnāt added that to their slicer yet.
In Orca, the calculation for shrinkage for your test model is
19.68Ć·20
=0.984 = 98.4%
In Bambu, you use the scale tool with the percentage below.
20Ć·19.68
=1.016260162602 = 101.626%
If you want to calculate the scale directly from the Orca percentage, use:
1Ć·0.984
=1.016260162602 = 101.626
Thatās the problem though. I dont want to have to scale or manually manipulate a model once it is in the slicer. I create it in Fusion360 to proper measurements, then drop it into the slicer and then slice it. I dont want to print a part to test measurements then another and another and another till I get the proper measurements. Many hours are wasted before I can confidently start a print, and thats not working for me.
With OrcaSlicer, I dont have to do that since the shrinkage compensation settings automatically scale the model for me, and that % is set and saved for next useā¦ Why is this not in BambuStudio? It requires too much effort and time when I try to use my X1C compared to my crappy printers.
You make it sound like the other printer is better, but it has absolutely nothing to do with the printer, it is just a slicer option. you are just using an OrcaSlicer feature that can be used with the X1C as well. Just use OrcaSlicer and if you canāt wait for Orca to get the newest Bambu features, use BambuStudio when you need those features. I mostly use Orca, but sometimes use BambuStudio.
You donāt have to make many test prints, you do a calibration print once, then record the result for the specific filament.