What size bolts are these?

Could we have that in English please?

TPI = Threads per inch. Yes the threads on the bolt are quite fine.
2BA = ???
Outside diameter is .190 (but I suppose .005" is not much - I'll check again.)


BA is the old Imperial standard for small screws used in electrical assembly and the like - British Association, they are generally available in even numbers 0 -2 - 4 -6 BA etc, the smaller numbers being the biggest dia.

If you do need them (or any other odd threadforms, in Oz) - try shops that supply to people sorting out old motorbikes. There are some photos here:

British Association (BA)

.
 
BA is the old Imperial standard for small screws used in electrical assembly and the like - British Association, they are generally available in even numbers 0 -2 - 4 -6 BA etc, the smaller numbers being the biggest dia.

If you do need them (or any other odd threadforms, in Oz) - try shops that supply to people sorting out old motorbikes. There are some photos here:

British Association (BA)

.

Thanks for that information. I've now book-marked a website in Australia. Thanks

https://www.classicfasteners.com.au/content/Classic_Fasteners_Catalogue.pdf
 
without having both diameter and TPI it is all guesswork. Instead of going to the expense of thread gauges etc I would pop along to your local engineering fastener supplier and enlist their help.
If you think it is a particular thread tell them they will pull a similar one from stock and lay it along side. If they mesh then its bingo first time , if not they will have a set of TPI gauges and vernier and go from there.

At least that it what my excellent guy would do.

Regards Clive
 
without having both diameter and TPI it is all guesswork. Instead of going to the expense of thread gauges etc I would pop along to your local engineering fastener supplier and enlist their help.
If you think it is a particular thread tell them they will pull a similar one from stock and lay it along side. If they mesh then its bingo first time , if not they will have a set of TPI gauges and vernier and go from there.

At least that it what my excellent guy would do.

Regards Clive

I've just been down to my workshop and measured the bolt

Diameter .1895 inch.
Threads per inch = (31-33) Say 32

That according to my deduction makes it BSF (fine)

Screenshot_2020-01-30 Threading Tables-Whitworth, BSF, etc - Thread_Tables pdf.png

I will order X5 today.

Thanks everyone for your help

Screenshot_2020-01-30 #10-32 (3 16 ) x 32 TPI UNF G304 Stainless Countersunk Phillips (PH2) Ma...png
 
Last edited:
yep it could be either of those and as has been said previously it could be 2BA unfortunately the thread pitch angles differ so they are not interchangeable.

So your route of buy a few and try is the best bet. My money would be on it being a UNF good luck.
As for repairing the bad thread hole DEVCON metal filled epoxy adhesive is good. Just grease the bolt well before putting it in the adhesive filled hole.

Good Luck Clive
 
yep it could be either of those and as has been said previously it could be 2BA unfortunately the thread pitch angles differ so they are not interchangeable.

So your route of buy a few and try is the best bet. My money would be on it being a UNF good luck.
As for repairing the bad thread hole DEVCON metal filled epoxy adhesive is good. Just grease the bolt well before putting it in the adhesive filled hole.

Good Luck Clive
Thanks Clive. You must be a good bloke (because my name is Clive too) :)

Clive Cooper
 
Top