[TR] Thread size for TR6 instruments?

[Tony Gordon]

My guess is that the threads are BA (British Association).  A very popular 
thread form for instrument makers in the UK.  If a 4mm die will run down the 
thread, than I'd guess it is 4BA (0.1417" dia and 38.5 TPI - 4mm is 0.1575" 
dia and a thread pitch of 0.7mm will give 36.3 TPI ... pretty close!). 
McMaster carries BA stuff I believe, but probably not the knurled nuts.
**************************************
Tony Gordon
72 TR6
**************************************
----- Original Message ----- 
From: "Greg Gelhar" <ggelhar at earthlink.net>
To: "Steve Smith" <dogzbody1 at yahoo.com>; <triumphs at autox.team.net>
Sent: Saturday, June 06, 2009 12:48 PM
Subject: Re: [TR] Thread size for TR6 instruments?


> Hi Steve,
>
> I have just tested some knurled instrument nuts with my tap set. I think 
> you will find those threads to be M4 x .7, one of the places there are 
> metric threads on our triumphs.
>
> Greg Gelhar
> 1973 TR6
> 1980 TR8
> Osseo, MN
>
> -----Original Message-----
>>From: Steve Smith <dogzbody1 at yahoo.com>
>>Sent: Jun 6, 2009 10:06 AM
>>To: triumphs at autox.team.net
>>Subject: [TR] Thread size for TR6 instruments?
>>
>>Hi all
>>
>>I hit a sped bump putting my gauges back in my car this morning. About 
>>half of the knurled nuts won't thread back on so either they were cross 
>>threaded previously (or I just cross threaded them!) or some are a 
>>different thread and I've mixed them up.
>>
>>Is it possible that some are UNF and some are other (BSF or Whitworth)? 
>>If that isn't the case I can run a die down the posts - it appears to be 
>>8-32, can someone conform this for me before I ruin my instruments?
>>
>>Thanks as alweays for all the help & advice as I bring this thing back to 
>>life.
>>
>>Steve
>>
>>1969 TR6 CC25805