MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - TD windscreen side supports

Before I screw these up, can anyone tell me the correct threads for these two studs ? I carefully tried to start a M8-1.0 tap into the wing nut & hex nut by hand but they got tight. I then measured the stud with a mic & thread gage and it measures .310 x 26 TPI, how is that possible. M8-1.0 is 25 TPI or close to it. Can I hear from the experts please? Scott
SM Scott

Should be a BSW thread. Only MAD Metric on T-Types are on the engine and transmission. I believe they are all M8x1.0
W. A. Chasser

SM - Good thing your stopped to ask questions - I didn't and got myself in a heap of trouble - of course that was quite a few years before anyone had home computers. I believe that the windshield fasteners are British cycle - I will have to find the site with the various threads threads - I'll get back to you and maybe someone else will chime in with the proper thread information. Cheers - Dave
DW DuBois

SM - I found the information I was looking for. The post you are looking at is 5/16 BSC. Stud size is 0.315 TPI - 26. Thread included angle is approx 60 degree.

For general information, fasteners used in the TD (with the exception of engine fasteners and windshield) is British Standard Fine, which uses the Whitworth size heads, except one size smaller, i.e. The size, across the flats of a 5/16 BSF bolt is the size of the head of a 1/4 Whitworth bolt.

If you two gentlemen will e-mail me at SUfuelpumps@donobi.net, I will send you information on the fastener system used on the T series cars, Cheers - Dave
DW DuBois

GREAT !! This car continues to frustrate me (grin), another goofy thread size, now where do I find THAT tap & die. Dave, thanks I'll drop you a note off-group. Scott
SM Scott

I got a cheap set of of ebay a while back. I only use them to clean up nuts and bolts so it's not stressing them that much. This is BSF.

http://www.ebay.com/itm/BSF-Tap-and-Die-Set-Bitish-Standard-Fine-20pc-Set-3-16-1-2-Whitworth-Fine-Thread-/262189473792?hash=item3d0bb5e000:g:mjYAAOSw~gRV4rWe


Here's a BSC set. Much more pricey.

http://www.ebay.com/itm/BSC-BSCYCLE-BSCY-CEI-TAP-AND-DIE-SET-26-TPI-BRITISH-MOTORCYCLE-BSA-NORTON-ARIEL-/201618666938?hash=item2ef168b5ba:g:mFoAAOSwX~dWsceb

Stuart
S Grimm

Hello Stuart, thanks for the t&d source, I have seen the BSF offering on EBAY before but not the BSC set. I guess the 5/16-26 is all I'll ever need or want so I'll find one somewhere. I have the BSF t&d when I got the car, think they came from ASL. Where are you in PA? Cheers................Scott
SM Scott

I believe BSC stands for British Standard Cycle. For quite a while I was under the erroneous impression that it stood for British Standard Coarse (Whitworth) as opposed to British Standard Fine (BSF). However the coarse Whitworth thread is simply known as Whitworth & the finer thread is British Standard Fine (BSF). Cheers
Peter TD 5801
P Hehir

Peter - You are correct, BSC is British Standard Cycle. Whitworth is correctly called British Standard Whitorth.
In case anyone doesn't already know it, Joseph Whitworth was the first one to come out with a standardized thread form, whichwas a course thread of specific thread form and pitch. It also had a ridiculously large head on the bolts. When later on they came out with the British Standard Fine (which has the same thread form as the Whitworth, but with a finer thread), it was decided that the heads didn't need to be so outlandishly large, but they didn't invent a different head, so they just put the next size smaller head on the bolts, thus a 5/16 BSF bolt has the same size head as a 1/4 BSW has, thus a mechanic didn't have to go out and purchase a completely new set of spanners. Cheers - Dave
DW DuBois

Well I'm still learning. I had no idea there was yet another British thread to deal with. Thanks Dave for the info.

Bill Chasser

TD-4834
W. A. Chasser

Bill.
just to complicate things there is a British Standard Brass Thread which is also 26 TPI but a slightly different thread form.
I have British M/C's as well as the TF so you can imagine how many tap and die sets I have.
I was trained when these systems were in use so I built up a collection over the years.
Ray TF 2884
Ray Lee raybar2(at) tiscalidotcodotuk

Hey Scott

I live over by Allentown. Used to live in Harper's Ferry. Sometimes wish I still did.

Anyway I found this place in the UK. Looks like they sell individual pieces. www.tap-die.com

Here's a page of Cycle taps. Only £9 for a 5/16X26 tap.

http://www.tap-die.com/contents/en-uk/d145_Cycle_taps.html


The dies are here. £15.75 for the 5/16x26.

http://www.tap-die.com/contents/en-uk/d159_Cycle_dies.html

They ship worlwide.

Later

Stuart
S Grimm

This thread was discussed between 14/07/2016 and 15/07/2016

MG TD TF 1500 index

This thread is from the archives. Join the live MG TD TF 1500 BBS now