Stanchion Hardware Search - Please Help!

[CPseudonym]

If you'd like to put this whole mystery to bed once and for all take 2-3 of these screws to a local tool and die maker(master machinist). Walk in Monday morning and offer to pay him to precisely identity your fasteners. It'll take him about 5 minutes with thread micrometers, pitch gauges and a machinists bible to end the mystery once and for all. While there he will likely be willing to tell you what size to modify to. He can also order replacements for you for a fee.

 

[sdowney717]

OK, I am chasing the BSW lead....the literature even mentions that they used smaller heads. And India = England in terms of manufacturing, right? Give me some hope!

BSW is the same diameter and TPI as UNC thread, only difference is thread angle, and the web link says UNC thread easily pairs with BSW.

https://en.wikipedia.org/wiki/Unified_Thread_Standard
Basically standard US thread should have worked if it is BSW.