Finding a uncommon nut size

[john west]

My ancient Tyford close coupled ceramic toilet cistern is held down to the pan by two butterfly nuts that screw on to Brass Bolts extending underneath the cistern. Being about forty years old the diameter of the bolts are 'between' the common 5M and 6M size. (i.e. bolt will not go into 5M nut and a 6M nut is too big). Would anyone know what kind of butterfly nut size and type of thread I should be looking for? Also how best to try to get hold of a no longer common sized one. Thanks.

[Andy Burns]

Could you not replace bolts and nuts together?

[charles]

Probaby a UNF size. In Guildford is an excellent shop that sell all sorts of scews & nut in all sorts of threads. But they are probably nowhere near you.

[newshound]

If you can't replace the bolts, you need to measure the diameter with a micrometer and thread pitch with a thread gauge to identify the size positively.

Once identified, Ebay.

[The Natural Philosopher]

Messingers still there?

Also Mackays in Cambridge...

And a few others

I assume you mean M5 and M6, so we are looiking for around 5,5mm

suggests that 7/16" Whitworth is a good place to start and te other possibilitity is UNC. I doubt that UNF would be used on a bog seat!

gives #12 UNC as the size.

You could probably ID which it is (UNF/UN/Whitworth) by counting threads per inch and looking at the thread profile. Whitworth is rounded and UNF/C is flat topped.

Hmm. It looks like actualy BSF/UNC/M is more likely than whitworth

Suggest you look here.

[Dave Plowman (News)]

Not sure Unified was very common except in cars and so on. Things like that if UK made were usually either BSF or BSW before metric.

[Muddymike]

Or the more course UNC. Mike

[Harry Bloomfield]

The Natural Philosopher laid this down on his screen :

They could also be a BA size, which was common for brass.

[Brian Gaff]

Whit worth, BSP?? Brian

[Andrew Mawson]

It won't be 7/16" Whit that's for sure - best part of 12 mm. 5/16" is far more likely

Andrew

[Brian Gaff]

I'm sure \i've seen unc unf whit and ba around on adverts quite recently. I think perhaps if it has to be the same, then the first job is to find somebody with a set of thread gauges to see what you are looking at. Brian

[harry]

There is probably one in the large tin of odd nuts I have in the shed. I thought every DIYer had such a tin?

[Michael Chare]

I bought my vice from them and possibly my drill stand.

[Bob Eager]

Talking of long established companies, anyone been to Dockerills in Brighton? I bought my first tools there, over 50 years ago. I was recently visiting (my son had a music conference just down the road) and I took the opportunity to buy some new Mole grips and a new pair of Maun side cutters.

It's a family form, and they how now reached the fifth generation!

[Bob Eager]

Or: "It's a family firm, and they have now reached the fifth generation"!

It's the lack of sleep (see other thread)

[Jeff Layman]

They disappeared a dozen years ago.

One might also ask what became of that fine tool shop in Tottenham Court Road - Buck and Ryan.

[charles]

No, they vanished about 10 years ago, the shop traded under another name - used to be a big firm in Tottenham Court Road (name I've forgotten), but they ceased trading about 4 years ago.

[charles]

Cathing up, Messingers sold out to Buck & Ryan but closed when tehn lease ran out. The premises were taken over by Cath Kidson, B&R lost their Tottenham Court shop due to rebuilding and moved to Southampton Row. They also had a tiny franche in Selfridges. They vanished about 4 years ago,

[tabbypurr]

Last time I went there everything in TCR had turned into red light district, no electronics left. Shame.

NT

[charles]

On Monday (2 days agho) there were a few computer shops and plenty of coffee shops - Red lights not obvious - but it was during the afternoon.