Right, The threads mentioned have the following pitches:
British Standard Whitworth (BSW) = 1/2" x 12
British Standard Fine (BSF) = 1/2" x 16
Unified Fine (UNF) = 1/2" x 20
British Standard Cycle Thread (BSCY) = 1/2" x 26
BertieB is using a Tiger Cub rear hub in his 'LF'. I have a Cub rear wheel spindle in front of me - it has 20 tpi spindle threads.
Ariel use 20 tpi.
So it makes sense to use 20 tpi for the new spindle as well - lets call that a decision
Now, UNF has a 60 degree thread form - which is what I propose to use. BUT what did Ariel use
I'll be turning the shaft on the lathe and also making the nuts, but I would like it all to be "Standard UNF" thread form - even if I make the nuts a bit larger than standard across the flats.
Bertie (not his real name
) doesn't mind what the spindle thread is so 20 tpi will be OK (I was going to say 'fine', but that might be confusing
I now need to clear up some questions with BertieB as his CAD drawing doesn't match the standard Cub Imperial bearing sizes
Thanks for all the input folks, that was very useful.
My avatar shows the late Len Rich in 1970 with the bike I now have - a 1958 Ariel VH