bolts size

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Andy51
Member
Posts: 742
Joined: Thu Mar 31, 2005 1:00 am
Location: BERKS UK

Re: bolts size

Post by Andy51 »

Hi, I have come a bit late to this, but BSC threads are NOT a BSF/Whit thread form. They have a 60degree thread angle, whereas BSF/Whit threads are 55 degrees. They do, however, all use the same hexagon sizes, but are most definitely not interchangeable. AMC used BSC on nearly all steel/steel fastenings, BSF on steel into alloy or cast iron, BA for small stuff and a few special threads for things like big end nuts that wise men leave alone! Cheers, Andy
JimFitz
Posts: 663
Joined: Thu Feb 27, 2014 9:27 am
Location: Kent, England

Re: bolts size

Post by JimFitz »

I will probably get my wrists slapped here but 1/4" BSF and 1/4" British Standard Cycle thread are close enough to interchange on non crical components, both being 26 TPI. The 5 degree difference in thread angle does not make a lot of difference.
The TPI is different in all other sizes.

Jim
Too old to Rock and Roll but too young to die.

1952 G80 rigid, 1960 G12 DL / Watsonian Monza, 1954 G80S.
cbranni
Member
Posts: 1439
Joined: Sat Oct 09, 2010 9:17 pm
Location: ABERTAWE UK

Re: bolts size

Post by cbranni »

I am with you Jim, (also expects a slap) a few degrees don't make much difference and the quality of threads these days you wouldn't notice. So lets not get into peak chamfers, root rads and effective dia.

Colin
only dead fish go with the flow
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