This metric screw fit/tolerance guide features horizontal bore holes for M3-M6 screws (3.00mm-6.00mm) with clearance to interference fits, designed to help you find the right dimensions for screw holes in CAD. With this guide in particular, you can test your printer's tolerances for horizontal bores, as they may be very different from vertical bores. Additionally, the layer lines in vertical holes run perpendicular to screw threads, further affecting results.

Finding the right hole size for a screw is difficult without testing first - in the best case you're looking for self-tapping holes with a fit tight enough so that the screw can live up to its highest potential, but without significant warping to the 3D-printed material. With this guide it's made easy for a variety of screws you might have on hand.