Are there reliable scale adjustment formulas for different plastics

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I’ve searched online and not found something that explains a good scaling ratio for different plastics. Do you have one that you use, that works?

For instance, I have an item that needs to pressure fit onto a non-3D printed item. I got everything dialed in so it will work in PETG.

What percentage should I enlarge the object in the slicer to make it likely to work with ASA?

When I looked online I saw info such as, “PETG shrinks .03-.05%, and ASA shrinks by .03-.07%” (or something like that). Well, it’s working in PETG, so I have no idea how to figure out the math on that. I’m hoping for something like, "Try enlarging it “(Some amount)” percentage and that should get you in the ball park for ASA, and when it’s PLA, shrink it by (This amount).

I’m hoping someone knows the answer to save me possibly hours of experimental prints to figure this out.

Thanks!

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I don’t think there is a proper answer to your question.
With the PETG brands I´m using, and well dry, the shrinkage is negligible if the printer is tuned and the filament is adequately calibrated. However, the calibration values differ from filaments and even within different lots of the same brand and model.
Is the print volume significant? What brand and filament model are you using?

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Well that is understandable because each type can have differences in actual shrink back even within the same group of filament materials. Some ASA filaments are blends with other polymer ingredients to reduce warping for example and those tend to have less shrink back than “pure” ASA filament.
As a beginning guide I resize objects printed with my ASA to 100.6% on both X and Y directions while Z remains at 100%

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Orca has a parameter in the filament profile for shrinkage, in percent and defaulting to 100. If I were you I’d print a calibration block (eg. 100x100x3 mm), measure it after cooling and use that. Make sure you don’t measure any elephant foot. It might be clever to use similar print settings as the part you’re going to produce, in terms of infill type and density for example.

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Thanks for the suggestions.

I thought about printing a calibration cube, but was hoping there was a standard that was already known. But, it makes sense that the most reliable is the cube.