XY-Calibration global vs. local

Hello everybody,

recently we got some issues with our refurbished Form2.
we are using a scaling print (see picture below) to measure and calibrate the scaling of the printjob.

we are using the “Fine Tuning” option for the calibration.
Recently we can’t calibrate good enough across the build area.
The 4 cubes, for example, have in cured state (grey) a x-dimension of 19.82 mm / 20.03 mm / 19.87 mm / 20.01 mm. So in the same print, there is a cube with -0.9% x-dimension (rel. to 20 mm / stl-file) and also one with +0.2%. Since we use the printed parts as a master form, this variance is critical for us.
The XY-calibration of the previous Form2 showed better and uniform results (19.99 mm / 20.01 mm / 20.00 mm / 19.99 mm).

So the question is, is the scaling variance across the build area usually as bad as we got right now?
Can it correlate with the refurbishing process of the second printer?
Did anybody experienced similar situation with his printer?

Thanks for your help

Best regards

Hi there,

I’m starting to look into the dimensional stability of my 3D prints and came across your post.
I was using a Form 2 with High Temp V1 resin to print molds for plastic injection molding. The molds are 60x60x5mm (X, Y, Z) in size.
Since the Form 2 broke, I switched to our Form 3 with High Temp V2 resin.
I felt free to copy and alter your design to (excessively) test how the parts come out and warp or shrink or do whatever can happen during printing, washing, curing, and baking:

image
(probably an overkill right now but it’s a start :slight_smile: )

I noticed, that my molds always came out bigger than the stl-part. And not only that: The cavity for the plastic injected part came out smaller than the stl-file. So I concluded, that the printed part swells. -It’s not off as far as your prints, only 0,07 - 0,22% (0,04 - 0,13mm) bigger in X and Y direction, but printed with 0,4mm support touchpoints and 1,5 support density, the molds came out 9,9 - 12,2% (0,51 - 0,55mm) bigger in Z direction. Nothing some sanding can’t fix but still frustrating when the molds only hold up for about 10 good shots.

Did you or anybody else also notice swelling on their parts, or does it only occur with High Temp resin?

Are you referring to the “Scale” option in Preform?
And are your parts’ dimensions off uniformly in X and Y direction or is there also a difference?
And are your parts printed correctly in height?

Sorry for posting more questions than answers. I’ll get some answers soon, hopefully.

Cheers,
C