Am I being dumb ?

[Neale]

Could you clarify what you are trying to fit to what? Somehow from what you've said you I don't think that you will find an off-the-shelf fitting but if we know what's needed it will be easier to advise. For example, is your "normal everyday 3/8" thread" UNC, UNF, BSF, BSW? Not to mention the finer threads in the ME series... Or maybe nearest metric size? It's all a bit of a rat's nest

BTW, I don't know of any thread where measuring the inside of the thread (as per your picture) will give you a recognisable dimension. Usually threads are measured over the outside - in effect, the diameter of the rod that an external thread was cut on. You can use internal diameter to find actual thread size but you will need to know what you are looking for in thread tables (possibly core size, give or take a bit of clearance).

[magicniner]

https://mdmetric.com/tech/thddat7.htm

Major and minor diameters plus all the other dimensions you could need ;-)

[Fivetide]

Could you clarify what you are trying to fit to what? Somehow from what you've said you I don't think that you will find an off-the-shelf fitting but if we know what's needed it will be easier to advise. For example, is your "normal everyday 3/8" thread" UNC, UNF, BSF, BSW? Not to mention the finer threads in the ME series... Or maybe nearest metric size? It's all a bit of a rat's nest

BTW, I don't know of any thread where measuring the inside of the thread (as per your picture) will give you a recognisable dimension. Usually threads are measured over the outside - in effect, the diameter of the rod that an external thread was cut on. You can use internal diameter to find actual thread size but you will need to know what you are looking for in thread tables (possibly core size, give or take a bit of clearance).

Ok Neale thanks for the reply, I'm trying to get to a point where I can screw in a 3/8" bolt to the bush after I've ground the head off and fit it into a chuck capable of taking up to 13mm. if that makes sense ?

[cropwell]

Have a look at https://www.bes.co.uk/products/160.asp. You might find something like an end plug you can drill and tap to your 3/8 bolt. Maybe you could just weld or braze the bolt on.

Oh the joy of BSPP BSPT and NPT. You can learn more at http://www.newmantools.com/taps/bsp.htm

Cheers,

Rob

[Fivetide]

Have a look at https://www.bes.co.uk/products/160.asp. You might find something like an end plug you can drill and tap to your 3/8 bolt. Maybe you could just weld or braze the bolt on.

Oh the joy of BSPP BSPT and NPT. You can learn more at http://www.newmantools.com/taps/bsp.htm

Cheers,

Rob

Hi Rob yep thought about these methods but if it out of center it would cause problems, I might take them into the local iron mongers find the right bolt and then find some kind person with a lathe to turn one end down to 10mm.. path of least resistance etc.

[Neale]

Ok Neale thanks for the reply, I'm trying to get to a point where I can screw in a 3/8" bolt to the bush after I've ground the head off and fit it into a chuck capable of taking up to 13mm. if that makes sense ?

Sorry but I have to ask again - what 3/8" thread? If it's an old bolt, then it might be (imperial) BSF or BSW, newer might be (unified) UNF or UNC. Might, just, if it's a bit sloppy on its OD, be M10, depending on how accurately you have measured it. You might end up having to buy a matching tap and making it yourself, unfortunately, unless you have a kind forum member nearby with a lathe and good set of taps!

Edit - I see that you've more or less reached that conclusion!

[Fivetide]

Sorry but I have to ask again - what 3/8" thread? If it's an old bolt, then it might be (imperial) BSF or BSW, newer might be (unified) UNF or UNC. Might, just, if it's a bit sloppy on its OD, be M10, depending on how accurately you have measured it. You might end up having to buy a matching tap and making it yourself, unfortunately, unless you have a kind forum member nearby with a lathe and good set of taps!

Edit - I see that you've more or less reached that conclusion!

Screw Size: 3/8" UNF x 1.1/2" long Thats what I found will fit in the chuck , thats why I thought it would fit in the bush.. that sounds naughty lol :)

[Fivetide]

I may have come up with a cunning plan :)
I found these Push Fit Stem Adaptors they may be strong enough for what I need , but if not I can cut off the stem and tap out the nut.. may work but hey I love a challenge :)

[cropwell]

I may have come up with a cunning plan :)
I found these Push Fit Stem Adaptors they may be strong enough for what I need , but if not I can cut off the stem and tap out the nut.. may work but hey I love a challenge :)

You maaaaay be asking a lot from Acetal, but you could always put a steel rod down the centre and bond it in.

Cheers,

Rob

[Fivetide]

You maaaaay be asking a lot from Acetal, but you could always put a steel rod down the centre and bond it in.

Cheers,

Rob

Shit ! I thought they where steel FFS ..cancel that order then :(