When designing for screw holes in your 3D model, a little tolerance is usually required for a good fit. This parametric SCAD model allows you to dynamically generate test prints with different tolerances and orientations.

You can print the test block with your preferred printer settings and material to see how the screws fit in practice and select the best hole diameter value for your model.

Usage:

• Measure the (largest) thread diameter of your screw using calipers
• Generate test print, e.g.: ScrewholeTest(screwDia=2.8, label="M3");
• Render and export STL; print with your settings (layer height, perimeters etc.)
• See in which hole your screw fits best