Due to technological limitations, 3D printing does not allow to obtain standard threads for immediate use as for CNC machining technology
We therefore offer you 3 solutions to be able to overcome this problem:
1) Draw the hole with the dimensions of the diameter as per ISO standards so that it acts as a pre-hole so that you can subsequently use a suitable tool to make the thread. We advise you to draw the hole 0.1-0.2mm narrower than the diameter in order to compensate for any printing tolerance of + -0.3mm so that you can pick up the hole with a drill bit before proceeding optimally with the threading.
2) Draw the hole already threaded on a 3D model; the recommended solution is for threads from a size starting from M5-M6, and then pick it up again with a suitable tool for threading following the trace of the printed thread. Also in this case it is recommended to keep a negative tolerance of at least 0.1mm on the drawing with respect to the ISO dimensions.
3) Finally, a further solution may be to exploit solution to create a suitable hole where you can insert Helicoil-type inserts; the service is not offered by us but only suggested among the possible solutions.