Hi,
.
I have a big model with small holes (m4 thread) and thin long elements.
After calibration, I found that the best value for X-Y hole compensation is 0.4mm.
At the same time, I’d like to use X-Y hole compensation only for the m4 holes and ignore big ones, otherwise the thin connectors become thiner that it’s needed for 0.8 mm.
You can use modifiers in Bambu studio and place them just where you want the compensation and change settings in that modifier. I think there is a tutorial somewhere around here
Thank you! I’m sorry, I just tried, but it seems the compensation settings are only global and can’t be applied to a modifier or even per-object.
May you please share the tutorial, maybe I do something in a wrong way 
?
If you upload the .3mf file here it will be easier to explain how to add modifiers to do this to your specific model.
Thank you, of course, nothing secret, please find it attached.
That’s the SkyWatcher 130 PDS retrofit taken from Thingiverse.
224.retro-tele-ppa-rc1.3mf (520,7 КБ)
After looking at the model I see that the threading features are actually in the model. This isn’t going to be something a modifier can replicate/enlarge easily.
That being said, why not leave the model as is and run a tap through the threads as a post process? That will clean them up and size them correctly.
I don’t know of any slicer that implements hole compensation in a useful way. In my experience, any concave wall is printed with a slightly too small radius. The amount depends on the curvature. So very big concave curves only are too small a little bit, while very narrow curves are far too small.
All slicers implement hole compensation for closed holes only while it affects open concave shapes as well. And there is also no adaption for different curvatures. So in my opinion, hole compensation is quite useless.
If it is your own design, you could make a small series of test prints for each hole size and choose the one for your actual model that fits best.
For high accuracy at low effort, I fully support the suggestion by @JonRaymond .
FDM printing is never going to be able to print fine threads (M4 and smaller) accurately. As Jon says just run a tap through to cut the threads correctly. I’d also suggest increasing the wall count a little to ensure you have enough material to keep a thread strong.
For parts that need regular assembly and de-assembly, using a threaded brass insert nut is the best solution.
XY hole compensation can help printing small holes accurately, but in my experience needs to be adjusted for each filament and setting, so only useful if you’re printing multiple copies of something with the same filament.
