Looking at early gunmakers craft. They could forge weld iron , they had copper to braze things togather , they bought imported files , but early on , they made their own files , chisels , screws and screw drivers , scrapers , etc.. I've never read that there was any standardization of threading dies and taps. Musta been whatever the purpose of the threds were for , those taps and dies , were made by the smith , or some smith down the street. Early on in my quest to try and understand , where did the raw materials come from , that early gunsmiths used? No supply houses around. In the 1980's , I visited an 1780's plantation near Franklin , Tn. The house chimneys , and other parts of the roof used copper sheeting as an interface between roofing materials and chimneys to insure water tightness. I asked the guy in charge if the copper sheeting was a new application , and he said the building was restored using the same materials as origionally used. From this , there would have been scraps from the roof work when the house was built , and nothing being wasted , the copper scrap went to a local blacksmith for brazing. I'm really in the weeds , and need to stop surmising , but no historical record reveals what was happening back then. Materials had to either be imported , recovered and repurposed , or made from local raw materials. .........oldwood