Threads fail in the field when class, depth, and counterbore requirements are unclear. Specify thread standard (metric coarse/fine, UN/UNF, etc.) and whether threads are cut, milled, or formed.
Blind holes need a drill depth that supports tap lead and chip evacuation—your machinist will translate drawing notes into tool lists, but contradictory depth callouts cause scrap.
For cosmetic faces, note if thread relief grooves or burr-free edges are required for plating or assembly.
When in doubt, provide a section view or a detail callout for the first thread feature in a new design.
