Armstrong Siddeley Question

[A. Siddeley]

Hi,

I have just joined the site.

Does anybody know the thread size for this mascot ? [url]

|https://thumbsnap.com/XpKHFuEt[/url]

Thank you

[A. Siddeley]

Hi DaimlerV8,

Thanks for the reply.

I had the same idea.

I went through my own collection and no luck.

Up the road we have an old shop that is very old; it has ancient nuts and bolts all stored in little wooden drawers, and mousetraps and ceiling wax and hairy string.

They could not match it, so I was wondering if it was a particularly unusual size ?

Kind Regards

A.Siddeley

[Grumbly]

Looks like a whitworth thread, what's the diameter? It's hard to judge scale from the picture.

[astonman]

I'd be very surprised if it wasnt BSF,British Standard Fine.Probably 1/4 or maybe 5/16.
If its smaller than 1/4 BSF, its 3/16 BSF or 2 BA.

[Huntsman]

BA I reckon.

[dudleybloke]

Can you measure the thread diameter and also count the threads per inch as this will help.

[finlo]

Remove it and replace with a metric thread?

[kimducati]

As already noted, it's a Whitworth thread form, the rounded peak on the threads gives it away.
Measure the o/d and it's that size Whit. Probably 1/4" or 5/16" at a guess.
Kim

[Mike-tf3n0]

If you post the od to 1 or 2 thou plus the tpi I should be able to identify it from my Zeus.

[a8hex]

Grumbly said:

Looks like a whitworth thread, what's the diameter? It's hard to judge scale from the picture.

Well it was owned by Armstrong Whitworth

[A. Siddeley]

Hi ,

It is good to find a site with so much knowledge.

I measured it and it is 0.246 inch.
I am not confident about the tpi, they are only little stubs.

Whitworth seems to be most proffered opinion.

So, I guess a 1/4 inch Whitworth.

I will order some and give it a go.

Thanks to everyone who replied.



👍

[Mike-tf3n0]

If it helps, a 1/4" Whitworth thread has 20 tpi. Just put a bit of masking tape around the thread with an inch between them and count the number of turns, your bit of thread doesn't look very long so 1/2" will have 10 turns.

[A. Siddeley]

Mike-tf3n0 said:

If it helps, a 1/4" Whitworth thread has 20 tpi. Just put a bit of masking tape around the thread with an inch between them and count the number of turns, your bit of thread doesn't look very long so 1/2" will have 10 turns.

Hi,

These callipers are set at exactly half an inch.
There seem to be at least 12; does that mean that it is not Whitworth ?

Thanks

[dudleybloke]

1/4"BSF is 26tpi so would be a good bet.

[A. Siddeley]

Hi . . . this is great . . . change of plan . . . I am now going for 1/4"BSF is 26tpi .

Thanks