Demonic69 Posted May 19, 2020 Report Share Posted May 19, 2020 Hi All I picked up a quick-release hose and adapter for my PR900 when I got the gun. The QR end is fine, but the other end of the hose doesn't fit in either of my pumps or the air bottle I borrowed. They're supposed to be 1/8BSP, but could they be 1/8NPT? They screw in for the first couple of threads, then bind up, leading me to think the thread pitch is slightly different. Any ideas? I don't have an imperial thread gauge to check if they're 28 or 27TPI. Cheers Quote Link to comment Share on other sites More sharing options...
washerboy Posted May 19, 2020 Report Share Posted May 19, 2020 Bspt even? Sorry I can't think of much more besides as you said npt. Quote Link to comment Share on other sites More sharing options...
old'un Posted May 19, 2020 Report Share Posted May 19, 2020 I would of thought that wherever you purchased them from would have given the spec for the threads? Quote Link to comment Share on other sites More sharing options...
Demonic69 Posted May 19, 2020 Author Report Share Posted May 19, 2020 9 minutes ago, old'un said: I would of thought that wherever you purchased them from would have given the spec for the threads? Yeah, he thought they were BSP, he's gone off to measure! Quote Link to comment Share on other sites More sharing options...
rovercoupe Posted May 19, 2020 Report Share Posted May 19, 2020 Sounds like a BSP/npt issue, a lot of the Chinese cheap hoses are npt, difficult to tell as I think it’s just the pitch that’s different. Quote Link to comment Share on other sites More sharing options...
figgy Posted May 19, 2020 Report Share Posted May 19, 2020 (edited) Some are 8mm metric I had this problem on China made stuff. I bought a new foster quick coupling it was easier than chasing fittings to suit. Easy to check with a M8x1mm bolt or nut. Edited May 19, 2020 by figgy Quote Link to comment Share on other sites More sharing options...
Andy H Posted May 20, 2020 Report Share Posted May 20, 2020 (edited) It probably is 1/8th bsp but add a t on the end and it becomes 1/8th bspt taper thread The top part of a bspt thread is bigger than a bsp thread and the lower part is smaller than a bsp thread so when you try putting 1/8 bsp male into a 1/8th bspt female thread it will only screw in 2-3 threads and stop dead. Edited May 20, 2020 by Andy H more information Quote Link to comment Share on other sites More sharing options...
oldypigeonpopper Posted May 20, 2020 Report Share Posted May 20, 2020 hello, what pumps have you ? Quote Link to comment Share on other sites More sharing options...
Demonic69 Posted May 20, 2020 Author Report Share Posted May 20, 2020 (edited) 6 hours ago, Andy H said: It probably is 1/8th bsp but add a t on the end and it becomes 1/8th bspt taper thread The top part of a bspt thread is bigger than a bsp thread and the lower part is smaller than a bsp thread so when you try putting 1/8 bsp male into a 1/8th bspt female thread it will only screw in 2-3 threads and stop dead. That sounds bout right, it's 10mm at the widest point, I'll check for a taper. Are the TPI different? I compared the 2 the other day and the threads seemed slightly off 2 hours ago, oldypigeonpopper said: hello, what pumps have you ? A Hill and a Webley, also borrowed a dive tank for a day. Managed to re-thread an adaptor to get it filled, but need something more reliable now Edited May 20, 2020 by Demonic69 Quote Link to comment Share on other sites More sharing options...
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