Other day Malc the scrappie called in for a cuppa and to see if he could borrow a 7/16" BSP die.
I said I'd never heard of one, didn't mean to say there wasn't one, just I'd not heard of one.
He insisted he'd got the taps but no die.
So looked in various books, World screw threads, MH, Machinery screw threads book but all list 1/4", 3/8" then 1/2"
Even the specialised tap and die people don't list one.?
Anyway he popped in again to day with a tap and sure enough it's clearly stamped 7/16" BSP x 19 threads and it looks to be about the right size, looks close to a 3/4" UNF as a guide size.
Even took a picture
It was parallel but I even looked under tapered charts and nothing.
I have plenty of old engineering books, in fact I collect them and have about 7 that have nothing but screw threads in them. One list threads that obscure it even lists Manchester Plumbers Thread for copper pipe, only used by plumbers in the manchester area.
Also it lists the original Whitworth pipe threads which are very slightly different from the modern ones but again no 7/16"
Interesting link but for experiance all the fuel fittings I have come across are 1/4" pipe. This 7/16" pipe thread is about 3/4 to 7/8" outside diameter which is large for a motorcycle fuel fitting.
Jason,
The tracy taps are 7/16" OD pipe is different in that the size is the hole down the middle of the pipe but I'm probably telling you how to suck eggs.
7/16" Is near to 1/4"BSP (but not quite), the thread number is the same. I have'nt been able to confirm it yet, but I seem to remember it as a gas thread, and I think the pipe size is the external size unlike water pipe, I'll have another dig and see what I find. Ian S C