@dave r said:

What version of SketchUp are you using? Your profile only indicates Free/Make and the Solid Tools aren't available for that version.

One thing that will help in your model is to make the cutter volume larger. Don't be stingy with the geometry.

Where did you get the component? It appears to be very poorly modeled with a lot of excess geometry and problems with misaligned circles that will result in very tiny faces even at the larger scale.

I would suggest first remodeling the component so you don't have all this bad geometry.
[attachment=0:1evq9zzp]<!-- ia0 -->Screenshot - 7_31_2022 , 10_45_39 AM.png<!-- ia0 -->[/attachment:1evq9zzp]

Do you still have the original .stl file? Will you share it?

Dear Dave,
Thank you very much for your response,
I'm helping remotely for a partner, the partner have a license and they are using is SU 2021.

The STL file is imported directly from the OpenFlexture science project : https://openflexure.org/projects/microscope/build
Here is the direct link to it : https://build.openflexure.org/openflexure-microscope/v6.1.5/optics_picamera_2_rms_f50d13.stl

Since it made using OpenSCAD by other team that's skilled in SCAD, I have no skill about OpenSCAD and don't know how to remodeling it. Is there any easier way to workaround?

I'm trying to use the Solid tool > Subtract to subtract 2 solid object (first object is the rectangular in the attachment). But the result is a non solid object.

Unfortunately, Solid Inspector can't help to fix it. I found this topic say that SU does not work good with small units (https://sketchucation.com/forums/viewtopic.php?f=15&t=31629) so try to scale the model bigger 100 or even 1000 times but still no lucky.

Is this a bug from SketchUp and is there any way to workaround?

2 solid object big scaled.skp