whitworth threads

this is a little off the subject of c/l stunt but considering the expertise/experience (and participation by the guys "across the pond")i figured i'd ask.
we recieved a worm gear speed reducer from a customer today and the thing is full of BSW threads (1/2-12). i need to find a supplier of whitworth thread bolts stateside to refurbish this unit. i found some in ny state but he wants to sell a min. of 500 and we only need 12. the cost for these bolts is pretty astronomical, and we want to make the refurbishment as economical as possible. any help would be appreciated!

Whitworth fasteners are no longer common in Australia, but still available from many suppliers.
I would be pleased to purchase your requirements and pass them on at cost.
More details would be needed, such as head type, length and material specs (although hi-tensile would be most likely).
Contact me off-line if I can be of assistance.
David Owen

Not stateside but this lot have been very helpful in the past:

http://www.nu-screwandnut.co.uk/

Tony

If you are stuck send me a list and I will see what I can do I am sure we could come to some arrangement I work in engineering, have many sources for this sort of thing, and would be happy to help if I can

Regards

Mike

http://www.mike-nelson.co.uk

thanks for responding......had a brilliant idea just a bit ago. called our local british car resto shop, and he has a bagful of 1/2-12 hex heads of the proper length (1 1/2) to satisfy my needs. in trade, i get to rewind a couple of alternators for him!

Most whitworth threads work with UNC threads, alas I think 1/2" is the only one that does not, the only difference is in the thread angle, whitworth is 55 degrees, I think UNC is 60.

The pitch is the same with the exception of 1/2" if my memory serves me correctly.

>Most whitworth threads work with UNC threads, alas I think
>1/2" is the only one that does not, the only difference is
>in the thread angle, whitworth is 55 degrees, I think UNC is
>60.
>
>The pitch is the same with the exception of 1/2" if my
>memory serves me correctly.
>
>Bazzer

Ron B.
F4Fguy

Bazzer:

While some sizes may coincidentally "go together",they certainly don't fit.British United thread form and U.S. are compatible(UNC) ,but not Whitworth. Whitworth has an entirely different form.Not only the angle, but, pitch, pitch diameter, and root and crown contours are different from UNC or SAE.

I'd also point out that neither "American" or metric wrenches will fit Whitworth bolts and nuts.

The British Car/Bike Shop is the place to go.

correct- BSW threads have a 55 degree thread profile, UNC and metric are 60 degree threads. the triumph restorer that i got the bolts from took me to school on BSW thread forms and the inherent dangers therein! NOW.....if anyone knows about Nelson hydraulic drives for dredge pumps..........

Another good place to got to is people who repair or restore British Motor-cycles.
There seem to be a lot of bad vibes about " Bikies " in USA.....
But I am certain these guys will be interested in what you want and will be pleased to help.......
If not.. tell them that as an ex-Velocette owner I will haunt them for ever.......more seriously I am sure they will help you.

ahh man! i have desired a Thruxton Venom for about eight years now! one day, i tell ya, one day!

If you get stuck Stateside here's another company who I've used several times (usual disclaimer). They post world wide. Prices on Website

http:/www.namrick.co.uk

LAST EDITED ON Nov-13-04 AT 00:23 AM (CST)
 
Just to add my bit on the Whitworth threads, ALL except 1/2" from 1/4" to 1" will screw together even though there are differences in thread form due to "commercial fit tolerances". However, under load, they may loosen due to deformation resulting from the 60 deg over the 55 deg angle of thread. 1/2 is the only odd one out as someone else pointed out with 12 tpi on Whit and 13 tpi on UNC. The most annoying fact of all is the Whitworth spanner sizes which are now generally unobtainable. Some metric spanners are close. LONG LIVE THE UNIFIED SYSTEM!

DH

PS

What is the BRITISH UNITED THREAD FORM as mentioned above somewhere?