[Feature Request] Automatic shrink factor calculation (Two Options)

Bambu Lab H2 Series
1

Calibrating the shrink factor is always PIA. The Calibration Plate is nice but often the shrinking is more than the accuracy of the motion system.

Proposal for a Bambu Studio Integration.

  1. Option
    Print a shape with “known” size ( like a 20x20x2 block) in bambu studio without any compensation on normal print plate.
    install calibration plate
    put printed part on calibration plate
    scan plate and there should be a “blind” spot where the block is on the plate.
    Due to the fact that we know the distance between the markers on the calibration plate we can now calculate the blind spot and then the shrink

Theoretically even when you lay the printed part not perfect on the plate you could extract the shape of it to compensate

  1. Option
    Use the same camera for calibration of the precise offset to calculate shrink :slight_smile:
2 Likes
2

unfortunately this wont work

3

Why would not? Please elaborate

4

shrinkage is not even and it’s very dependent on temperature, cooling, filament, additives, geometry…

too many variables so non of the approaches you described above would work. Even classic shrinkage calibrations (by measuring target parts like Fleur de Cali / Calistar) would not provide a consistently reliable result.

5

I think this is an excellent idea and should be well possible.
@hotellonely, how do you come to the claim that shrinking is not even? In my opinion it is a material property that some manufacturers even state in their datasheets. Of course it would have to be done for each filament individually as part of a filament profile. Like, when you determine K-value and flow factor. Those are too valid only for a specific material, temperature and other settings. then another test that goes into the profile would be automatic shrinkage determination.

Maybe you refer to warping and the size of small holes? Those are caused by shrinking but they are secondary problems, that will stay, but it still makes sense to correct the dimensional deviation if that is possible.

@PCR , just because you mentioned a 20x20x2 block for calibration: That sounds very similar to the ubiquitous calibration cube. In case that is what you use now, I want to encourage you to watch this excellent video:

Maybe you want to switch then to this calibration model and guide instead:

2 Likes
6

Great idea. Its like the last thing they would need to automate and seem to have all the tools needed.

7

Was just a quick idea. Sure there are better geometries for it. Other industrial printer manufacturers doing it too.

XY shrink are normally pretty homogeneous. I calibrated dozens of filaments in my 13 year 3d printer journey. Once calibrated it does not shrink so different each time.

Again I am for option 2 to print and then measure on the plate like with the precise nozzle offset as this is the simpel approach.

Best

1 Like