Looking for help with Older Triumph

[Michael C Henry]

I have a replica that used a 62-76 Triumph steering column. My current problem is Ii have the steering wheel removed exposing the upper shaft and need help describing the threaded end. I measured the threaded end OD with a Vernier caliper. It comes out at 13.08 MM or .5028" and my metric thread pitch gauge matched at .90 Can anyone clear it up for me. ?

[xb-60]

Mike,
I've checked in my trusty old Zeus booklet. 13.08mm is 0.515", so your thread is not a standard metric thread, and if we look at Imperial threads, 0.515" (or your quoted 0.5028"), there are no matching threads.
Closest I could find is 1/2" UNF ....OD is 0.5" and pitch is 0.050" (1.27mm), so no cigar.
1/4" BSP has an OD of 0.518" and pitch of 0.0526" (1.34mm), so still no good to you.
There are no standard metric threads that are even close. Standard metric OD's in your required range are M12 and M14 with standard pitches of 1.75mm and 2.00mm respectively.

Good luck!
Glen

[MOTORHEAD]

whitworth ?

[strictlypersonl]

Whitworth or possibly proprietary thread.

FYI, metric thread is rare in British cars before the '90s.

All the Triumph Spitfire column threads (mid-70s) that I have are .562" diameter.

[Austin_Snake]

All Triumphs used the same nut from the 50's til they closed down. Should be a 9/16-27.
If you need a shaft or nut go to Mossmotors.com

[Michael C Henry]

My column and steering wheel is exactly like the picture 62-76 Triumph Spitfire. Moss motors still has the nut but what I want is be able to describe the threads on a drawing. What is the type and so on. What do I call it?

[xb-60]

Originally Posted by MOTORHEAD

whitworth ?

1/2" BSW (ie Whitworth) pitch is way too large at 0.0833" or 2.12mm, so I didn't even mention it, and 1/2"BSF pitch is 0.0625" or 1.59mm

[Austin_Snake]

Originally Posted by Michael C Henry

My column and steering wheel is exactly like the picture 62-76 Triumph Spitfire. Moss motors still has the nut but what I want is be able to describe the threads on a drawing. What is the type and so on. What do I call it?

Pretty sure its 9/16-27 UNS. I can look in my Triumph Shop Manuals this weekend and verify the thread. They are usually more detailed than the part resellers. In the meantime check the Triumph forums.
Making a new steering column?
Regards,
Richard

[Michael C Henry]

OH crap, I just put away my tap and die sets. I usually do not do put away very well. I found on the computer, a "BSC" (British Standard Cycle) that shows a 9/16" (0.5625" x 26 TPI) I'm still looking for a name I can really trust to list on this mechanical drawing. when I had the thread pitch gauges out my fractional tap and die set 27 and 28 TPI were awfully close matches. I should have gotten more light and a piece of white paper as a contrasting back ground. Other than the Wentworth I have never heard of these thread systems before. Talk about living in a BOX.

[patrickt]

If it were me, I'd post my question on the Triumph Club's website... in the U.K. https://www.clubtriumph.co.uk/

[Michael C Henry]

I did look up UNS and they do show a 9/16"x 27 TPI. No experience with UNS . but it seems to fit my parameters. McMaster showed UNS 9/16" x 16-20-27- and 32 tpi I never heard of UNS before. but it seems to exist. All this is to complete a mechanical drawing I asked my Son to create for me while my steering shaft is exposed with the steering wheel removed. I want to have accurate information.