What thread is this?

[Andrew TinsleyParticipant @andrewtinsley63637]

I have some Bernzomatic 400 gm propane cylinders. I am baffled by the connector thread on these bottles It appears to be a male 1″ x 18tpi as best as I can measure. Is this some obscure American gas thread?

I certainly can’t find it in my readily accessible literature, or on the web.

Regards,

Andrew.

[David JuppParticipant @davidjupp51506]

Might be CGA 600 fitting, but I so far haven’t found definitive thread details.  May well be left hand threaded as it’s a flammable gas.

https://www.bernzomatic.com/Products/Fuel-Cylinders/Hand-Torch-Cylinders/14-1-oz-Propane-Hand-Torch-Cylinder-TX9

[JasonBModerator @jasonb]

I think they are 1″ x 20 UNEF Righthand, the smaller ones are 7/16″ x 28 UNEF

[Andrew TinsleyParticipant @andrewtinsley63637]

Hello,

Certainly a right handed thread, It is definitely 1″ OD and may well be 20 TPI. I should have got a magnifying glass to check the fit of the thread gauges. I will do that now. UNEF is a new one on me and I thought my knowledge of screw threads was pretty good!

Andrew.

 

[JasonBModerator @jasonb]

All the various UN threads here

https://www.sizes.com/tools/thread_american.htm

[DC31kParticipant @dc31k]

I am wondering if people’s search results differ by age, interests or geographical location.

When I look for ‘400g gas cylinder thread’, the 1″ UNEF comes up multiple times, including (for me) this eBay listing at the top of the list:

https://www.ebay.co.uk/itm/202386339887

[Andrew TinsleyParticipant @andrewtinsley63637]

I can confirm that the thread is indeed 1″ x 20tpi.  Web searches are sometimes a pain. Results depend critically on choice of words and even word order. For example Bernzomatic 400 gm cylinder thread gave no results, it also depends on the search engine used.

Andrew.

[not done it yetParticipant @notdoneityet]

Maybe because ‘gm’ is not a recognised SI unit?

[Michael GilliganParticipant @michaelgilligan61133]

Perhaps I hit lucky, but this looks quite a helpful page

https://bernzomatic.nl/featured_item/bernzomatic-gas-types-explained/?lang=en

… they are inviting requests forassistance !

MichaelG.

[Speedy Builder5Participant @speedybuilder5]

Looking at that link Michael, it shows how to solder aluminium – Not in English, but it shows how its done.

Bob

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