Thread type for the factory pressure gauges on a GX CS3 ?

[HajjitheDoberman]

Howdy folks,
I have a new GX CS-3i , that came with a cheap pressure gauge. I want to purchase a WIKA for a replacement. Anyone know if GX uses NPT or other type of thread?
Thank you!

 

[Heavyopp]

Should be metric

M10/1.0 thread pitch - most likely need an adapter

 

[two4spooky]

It may be BSPP thread pattern instead of NPT. I had the same question regarding different part on a different GX compressor. Best I could figure BSPP was what I needed. Still waiting on the fitting to arrive to confirm.

 

[HajjitheDoberman]

BSPP appears to be the type. I filled my 85cf SCUBA tank with the CS3i yesterday, and in doing so, found out that the moisture filter with bspp fittings leaked, since nobody at the jolly old Chinese factory could be bothered to actually tighten the fittings with a wrench. I tried the bspp fittings on the CS3i, and they worked fine.

 

[Heavyopp]

BSPP and metric are very close but not the same. BSPP will thread into M10/1.0 but will be hard to thread. You can force it with tools, you will not be able to thread the parts together by hand.
Since you are sealing on a washer it will work.

If you tried a metric threaded M10/1.0 you will find that you can thread all the way down to the sealing surface of the bellville washer by hand then just a snugging with a wrench is all you need.

Keep in mind my GX compressor is over a year old. Threads may have changed.
It is china, I would expect metric over British threads to be the norm for them.

 

[two4spooky]

Not an expert in this area so take what I say with a grain of salt. I thought NPT and BSPP(parallel)/BSPT(tapered) were thread patterns. Size is a different measurement and can be metric or inch. SAE(US) would be NPT for air, gas, hydraulic and such. Or standard patterns (plus class)for fasteners. The BSP are patterns used in UK, Europe and Asia for air, gas or what ever of which ever measurement(metric/inch). Difference being thread size vs thread pattern. PS - A Dowdy washer *I guess* could compensate for some differences regarding sealing. Like I said... grain of salt

 

[two4spooky]

PSS - The part I was looking for is available in either 1/8" BSPP to 8mm male or 1/8" NPT to 8mm male fitting size. I went BSPP sizing for my GX compressor based on country of manufacture plus observation. I believe my choice is correct. Will know shortly. If incorrect I will respond to this thread.

 

[two4spooky]

I was mistaken. On my GX the thread is not BSPP, not BSPT nor NPT. Original part threads are parallel, confirmed with calipers, at 9.94mm O.D. using no Dowdy washer, no o-ring or any other washer. The 1/8" BSPP I ordered has 9.63mm OD but thread patterns do not mesh. Is there such a pipe thread as CSPP(Chinesium Standard Pipe Parallel)? IDK. So a 10mm thread would likely thread on. Just wanted to correct my previous post incase some one else might find helpful.

 

[Heavyopp]

It’s 10mm 1.0 thread pitch. In stock form it seals on the delrin donut thats in the hole. It’s difficult to get that seal out if you must. I’m fairly certain I left mine in there and used it.

As I said above, bspp threads are really close but not quite right. The bspp will thread in there forcibly.