# Electronic – PCB enclosure tolerances

alignmentenclosurepcbtolerance

I can imagine problems of PCBs not fitting into their enclosures or misaligned screw/hole pairs. Are these type of problems common, especially with the dirt cheap enclosures?
I am planning to use one that has a "0.8 mm tolerance". It does not specify where exactly this tolerance comes in though.

Similarly, allow generous hole sizes for mounting holes- use at least the "loose fit" diameter in mechanical engineering sources$$\^1\$$. As well as linear shrinkage, bosses can bend a bit (the part is a bit soft coming out of the mold) if it is not handled perfectly.
$$\^1\$$You can find that information online- look for "tap drill" tables, but the real bible, in North America anyway, is Machinery's Handbook.