Hi,
My home compressor has a dual presta / Schrader attachment i don’t care for. I also have a co2 inflator head lying around. Hence the idea to for it to my compressor inflator hose.
Where I’m getting stuck are the thread sizes. On the compressor side, I need a 1/4in female npt fitting.
On the inflator side, Google claims that co2 cartridges have a male 3/8 npt thread. That doesn’t seem to be correct: the 3/8th male thread OD is given as 17.1mm, but i measure closer to 10mm on my co2 cartridge.
Am I right in believing that I need a 1/4in female npt to 1/8in male npt to connect my inflator?
Thanks for the help, tech heads!
The thread is 3/8 UNF (Whitworth form, 24 TPI), not NPT.
1/8 NPT is 27 TPI so it won’t work.
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Thank you! It doesn’t look like a npt to unf adapter is readily available. I guess that kills that idea.
Both AN-3 and 3/8 SAE use 3/8 x 24 threads, there will be NPT adapters available. AN = Air Corps / Navy, SAE = Society of Automotive Engineers. These fittings are commonly used on cars etc.
BTW if you are in Australia, as seems likely from the timing of your posts, your compressor fittings are unlikely to use NPT threads. NPT is a Septic standard, we use the international standard, ISO R thread (which is basically BSPT with the names changed so 1/4 BSPT becomes ISO R Dash 3) except nobody bothers with the ISO official names. so it is still called 1/4 BSP.