Threaded Screw Hole

Threaded Screw Hole is a tapped hole with the head seat already done: pick a metric size and a head type, drop it on a face, and it bores the tap-drill diameter, cuts a real ISO 60-degree internal thread on the wall, and recesses the head so the screw finishes flush or just below the surface. A matching screw threads straight in — no tapping, no insert, no separate counterbore feature to line up by hand. The thread is a genuine ISO metric thread at the size's coarse pitch, not a cosmetic groove: 60-degree profile, tooth depth around 0.6 of the pitch, and it carries through to the exported and printed mesh. The head recess follows the standard for the head you choose — a cylindrical counterbore for socket cap (ISO 4762), a 90-degree cone out to the flat-head diameter for countersunk (ISO 10642), and a shallow counterbore for button (ISO 7380) or pan heads. Thread depth sets the engagement, and Head seat clearance sinks the head slightly below flush, or as deep as you want it buried. For a printed thread, keep the axis vertical and prefer M3 or larger; the very fine pitches of M2 and M2.5 print marginally on FDM. As engagement, 1.5 to 2 times the nominal diameter is a sound rule for full strength in plastic — below that the thread strips before the screw does.