Scale and accuracy issues...

[jsapp1970]

I use Anycubic Standard Resin V2 with an Elegoo Mars 5 Ultra printer. I have designed several objects in 3ds max (2024) which have elements like nuts/bolts, or guide pins, for some examples. These elements fit together in 3ds max (2024), and all objects have their x-forms reset and pivots are set to 0/0/0 before exporting. I have tried exporting as .obj and .stl files. My Chitubox Pro slicer settings are 0.02 layer height with a 2.7 s exposure.The problem I am having is that, once printed, nothing fits together anymore. Bolts don't screw into the nuts (always too big), and guide pins don't fit the corresponding holes (always too big). What is the trick to get things to fit together after printing the same way they do in the design phase? Is there a setting that I am missing in the slicer (if anything is scaled in the slicer, I use uniform scale settings)? Or is this an export setting from 3ds max? Any help would be appreciated. Thank you in advance.

[airscapes]

Never used a resin printer but have been printing FFF for years. my holes are always .4mm smaller than the designed model.. So when I design anything I make that adjustment to sizes. I do not believe there is a fix.. you just have to design your items for 3d printing and that means knowing now much bigger or smaller to make things (trial and error testing) so they work. If I am making a object that interfaces with a machine part I do test prints for the interface piece before I design the rest so I don't waste a lot of time with printing an object that does not fit. You also have to take into account material shrinkage and I guess in the resin world you have to think about the resolution of your display device that is illuminating you resin layer with UV or however it works. Pixels are square so making something round will either be bigger or smaller. Display a small solid circle on your monitor and look at it with jeweler loop to see what I mean..