Jimmy Suarez wrote:
can somebody tell what kind of thread is this?
http://www.signaturehardware.com/product8636

it is for an old fashined door knob spindle,the thicknes is 9/32
square stock, and 20TPI,is there a nut or bolt made for this thing? Thanx


I've seen those before on many occasions in the UK. If your stock is
9/32 AF then that would give 0.398" across the corners if perfect but
they're usually rounded, I would hazard a guess and look at 3/8" BSF
which is 20 tpi. I understand Whitworth was used in the US for a while
but BSF only came about in the early years of the 20th century, BSW
having become a standard around the mid 19th century.