Nut and Bolt threads

[SeanF]

Dear all,

 

This is probably really basic to some, but I have great difficulty identifying which bolts to use with which nuts and usually end up in trouble!. I have no knowledge of threads etc and I don't know where to start. The most recent example is the captive nuts in the front inner wings to attach the bonnet hinges. I have fitted / am fitting, two new inner wings to my car, and am attempting to fit the bonnet to check the gaps as I go. I have a set of varied imperial nuts and bolts from Wrights (I think) and selected a bolt which seemed to work with the captive nuts in the new inner. (The old wings had a collection of different sized nuts welded in, all of which were different so can't be used). However after a few turns, the bolt became tight. I applied some wd40 and continued in the assumption that the primer in the threads was causing the tightness and would work through. However after a few more turns, the captive nut broke free and started to turn with the bolt. It would be great if there was a complete kit of nuts/bolts available to purchase for a re-build with labelling as to which bolt/nut goes where. Does such a thing exist, and if not, How do I identify which bolts to use where, with the most urgent being the bonnet hinge bolts!

 

Many thanks for your help,

 

Sean

 

 

[littlejim]

From memory just about all the bolts on the 4A were UNF. I think there were a couple of UNC somewhere around the gearbox

The Moss cattledog is a very handy reference for TR restorers

[John Morrison]

Hi Sean,

 

Inner wing fitting are 1/4 UNF, indeed most of the body bolts on a TR are 1/4 or 5/16th UNF.

 

Good pracice is to run a tap up a captive nut, that have been used before, if it goes tight,

 

quickly then you have to large a diameter, or the wrong thread and stop, you will soon learn the two or perhaps three

 

you will need.

 

Also all the usual culprits do wing fitting kits, all the bolts, nuts and washers you need for one wing.

 

John.

[bob-menhennett]

Sean

Just to elaborate on John's post. Order up a Moss Catalogue ( one free per customer ) each illustration of the relevant section throws up the part number of the screw ( threaded all the way along ) or bolt ( a bit of plain shaft and then threaded ).

 

Armed with this info ....in the General Hardware section at the back of the catalogue you can identify :

Type of thread

Spanner size

thread size

Screw or bolt length

There is an explanation of the Part No Codes e.g. BH bolts SH screw and numbering system

 

Nuts

Plain

Half size

Slotted

Nyloc

Brass Manifold

Spring / Spire

Captive Nuts / Cages

 

If the part number is not listed in this section , then it is a specialist fixing.

 

Bonnet hinges

You need 10 ( ten ) for the bonnet , 5 each side. Part Number GHF103 = Screw ( Threaded all the way along ) 5/16" UNF thread . 1" long. 1/2 " spanner to fix.

Plus washers of course.

Bob

Edited November 14, 2016 by bob-menhennett

[Ian Vincent]

Macy's the US TR specialists offer complete SS fastener sets for TRs. The problem is that they won't ship outside the US any longer.

 

Rgds Ian

[RogerH]

Hi Sean,

+1 for the Moss cat. Generally UNF bolt P/No start with a 6........ UNC start with a 5..........

example from the Moss cat - BH605161

B = bolt - this has a plain shank under the head if it was SH then S=screw - no plain shank at all

H= Hex head

6 = UNF 5 = UNC

05 = 5/16 ( the number is in 1/16 muliples) 4= 1/4 (4 x 1/16)

16 = 2" The length in multiples of 1/8" -- 10=1"

The 1 on the end is the finish

 

If you have a bolt that is tightening as you screw it in it may have a dirty/damaged thread or the WRONG thread.

If you put a UNF tap down a UNC hole there will be little thread left to use - and vice versa.

 

Most body threads are UNF.

 

Think twice about stainless bolts/screws. They normally do not rust. But is the steel around them rusts then the Stainless steel will deteriorate and the bolt/screw will get stuck in the hole. You could use a thin smear of grease/copperslip but then will the bolt/screw remain tight in the hole.

 

Roger

[Lebro]

S Steel + grease will last for decades.

 

Bob.

[BlueTR3A-5EKT]

Sean

Just to elaborate on John's post. Order up a Moss Catalogue ( one free per customer ) each illustration of the relevant section throws up the part number of the screw ( threaded all the way along ) or bolt ( a bit of plain shaft and then threaded ).

 

Armed with this info ....in the General Hardware section at the back of the catalogue you can identify :

Type of thread

Spanner size

thread size

Screw or bolt length

There is an explanation of the Part No Codes e.g. BH bolts SH screw and numbering system

 

Nuts

Plain

Half size

Slotted

Nyloc

Brass Manifold

Spring / Spire

Captive Nuts / Cages

 

If the part number is not listed in this section , then it is a specialist fixing.

 

Bonnet hinges

You need 10 ( ten ) for the bonnet , 5 each side. Part Number GHF103 = Screw ( Threaded all the way along ) 5/16" UNF thread . 1" long. 1/2 " spanner to fix.

Plus washers of course.

Bob

 

 

For packs of UNF assorted bolts have you looked at the offerings from the likes of Namric or the 'Bay?

 

Look at this sort of thing :

http://www.ebay.co.uk/itm/650-PIECE-UNF-NUT-BOLT-AND-WASHER-KIT-JAGUAR-TR-MG-EB153-/400897790053

or

http://namrick.co.uk/acatalog/

 

 

An aside.....

As the writer/creator of that section of the Moss cattledog (I like that term) I wanted to give the user a fighting chance of getting the right hardware and fasteners for their car. As time (and cattledogs) progressed I was called upon to create similar sections for other model ranges - my favourite was the more complete section in the Moss Sprite & Midget Mk IV & 1500 catalogue which myself and Mr Ploppy (Head graphic designer of Ploppy and Twinkle Design) put together in a day. That section went on to form part of many Moss parts publications. (TR7 was of course unique as it is metric based)

 

Cheers

Peter W

[John Morrison]

Sean,

 

you have PM.

 

John.

[SeanF]

Many thanks all for your replies. John, I have replied to your PM.

 

Best,

 

Sean

[kob666e]

 

An aside.....

As the writer/creator of that section of the Moss cattledog (I like that term) I wanted to give the user a fighting chance of getting the right hardware and fasteners for their car. As time (and cattledogs) progressed I was called upon to create similar sections for other model ranges - my favourite was the more complete section in the Moss Sprite & Midget Mk IV & 1500 catalogue which myself and Mr Ploppy (Head graphic designer of Ploppy and Twinkle Design) put together in a day. That section went on to form part of many Moss parts publications. (TR7 was of course unique as it is metric based)

 

Cheers

Peter W

 

Just my tuppence worth: currently restoring a Scimitar GTE and replacing all bolts like for like. The only problem now is that because the modern UNF nuts are larger/taller than the originals most of my new bolts are now too short as there is not enough of a bite in the nyloc.

 

So my word of caution is order the next length of bolt available to accommodate the bigger nuts.

[ed_h]

Don't know if you have something similar to McMasters or if they ship overseas, but they carry various kinds of "thin" lock nuts.

 

https://www.mcmaster.com/#hex-locknuts/=151fmqd

 

Ed

[wheeler]

Sean

 

This may help https://view.officeapps.live.com/op/view.aspx?src=http://www.buckeyetriumphs.org/technical/TR6_SSFasterners/Stainless_Steet_%20Fasteners_for_TR6.xls

 

Bill

[boxofbits]

Hi Sean

 

I think most points have been answered in is thread, but be aware that if you insert bolts which are too long into the threads on the bonnet for the hinges, you will end up with a nasty raised bulge on the bonnet surface, due to the long bolts hitting the bonnet skin.

 

Yes I have the T shirt by the way!

 

Kevin

[Alec Pringle]

There weren't a great number of nyloc half-nuts utilised on the TR range, but there are some (drive train for example) and you do need to be aware of them . . . . the Moss paper catalogue is your friend here, as are the factory workshop manual and parts book.

 

I do recall working on an early Scimitar GTE in the late 70s, it featured half-nuts all over the place, we assumed it was a Reliant economy and weight saving measure resulting from too many years of building three-wheelers . . . . .

 

Cheers

 

Alec

[SeanF]

Hi Sean

 

I think most points have been answered in is thread, but be aware that if you insert bolts which are too long into the threads on the bonnet for the hinges, you will end up with a nasty raised bulge on the bonnet surface, due to the long bolts hitting the bonnet skin.

 

Yes I have the T shirt by the way!

 

Kevin

 

Thanks Kevin. Its the bolts from the hinge to the inner wing that I am struggling with (specifically the threads on the captive nuts in the inner wings) . However following some excellent advice from John, my new tap and die set arrived in the post today so hopefully I will be able to solve the problem.

 

Many thanks all for your help on this.

 

Sean

[Don H.]

The TR I'm most familiar with, the sidescreen series, has every single fastener identified in meticulous detail in the Spare Parts Manual, 4th Edition (SPM4E). It's in the TR4-4A spare parts manual too, IIRC, and I expect the other cars as well. There's a S-T publication called "Hardware Catalog for use with Standard Triumph Vehicles" that decodes each fastener part number (the original numbers are obscure) into an actual piece of hardware one can look for. Scanned copy of both SPM4E and Hardware Catalog are easily found online.

Edited November 17, 2016 by Don H.

[SeanF]

Thanks Don

[stuart]

 

Thanks Kevin. Its the bolts from the hinge to the inner wing that I am struggling with (specifically the threads on the captive nuts in the inner wings) . However following some excellent advice from John, my new tap and die set arrived in the post today so hopefully I will be able to solve the problem.

 

Many thanks all for your help on this.

 

Sean

Those bolts are 5/16" UNF

Stuart.

[BlueTR3A-5EKT]

Hardware catalogue http://www.canleyclassics.com/standard-triumph-hardware-catalogue

[SeanF]

Thanks Stuart and Peter