The BSA A7-A10 Forum

Bikes, Pictures, Stories & more => Chat, Offtopic, Meetings & Everything Else => Topic started by: jachenbach on 06.06. 2015 03:36

Title: Whitworth nomenclature and good USA supplier of hardware
Post by: jachenbach on 06.06. 2015 03:36
I finally bought a set of Whitworth thread pitch gauges from British Tools and Fasteners (www.britishfasteners.com). I've bought a few things from these folks and have been very pleased with quality and service, so USA britbike owners may want to check out their catalog. They have tools, including taps and dies, lots of hardware, both singly and in sets, e.g. I got a complete engine/trans mounting bolt set. Good prices.
   Anyway, I got a set of thread gauges and measured the pitch as best I could for the front axle that I need for the RGSS. The gauge that seems to fit is marked 18g 5/16. I assume that's 18 threads per inch and 5/16" diameter (obviously way too small) per my reading of Whitworth nomenclature on Wikipedia. I'm wondering what the "g" means? Figure I can use a caliper to make sure of the diameter.
Title: Re: Whitworth nomenclature and good USA supplier of hardware
Post by: duTch on 06.06. 2015 09:42

 Hiya Jacho; RGS is out of my league, so I'm only guessing, but will suggest that maybe it should be a coarse cycle thread (20tpi BSC/CEI) *dunno*, simply because as far as I'm aware most threads on pre-units are either BSC 26-20/WW or some BA/BSF(where some of these components are not actually BSA, but in common with other marques-except head bolts)..
 
Maybe throw us a piccie, but surely some of the guys who know will sort it out.... *beer*
Title: Re: Whitworth nomenclature and good USA supplier of hardware
Post by: trevinoz on 06.06. 2015 23:08
If it is an 8" single sided front hub, I think that you will find it is 9/16" x 20 tpi, left hand.
Title: Re: Whitworth nomenclature and good USA supplier of hardware
Post by: jachenbach on 07.06. 2015 15:57
Sounds about right, but I'm still curious, what is the meaning of the "g" in 16g 5/16?