Fill station oring

[Franklink]

I bought one of the hand tight, CGA347 fill stations from ebay. Lots of different brand names but they all look pretty much the same, most even have the same stock photos.

Like this:

I'm having trouble with the orange oring in the above pic. It came with two, but both of those only lasted me a few months.. Tried Ace and got close but still leaking. Made an order from the oring store and got closer but still leaking. Made another order and I feel like I nailed it on the correct size, when compared to the orange ones it came with, but it's still leaking starting around 3200psi. 

What I came up with was 2mm x7.5mm, and could only find 75 and 70 duro. I would have liked a 90 duro but this item, "2mm X 7.5mm V90 FKM Fluorocarbon 90 Durometer " is telling me back-order when I put it in my cart. And it doesn't look like this size is made in BUNA 90 duro. 

Weird thing is that the orange ones don't feel as hard as the 90 duro that I have in a different size. 

It's being used with a Drager SCBA. The little holes in the threads on the valve are cutting little half-moons into all the orings that I've tried. 

So, do I still have the wrong size or is my durometer wrong?

 

[Eaglebeak]

I've seen lots of posts on that type of interface in the past. It seems that the O-rings are prone to being pinched. It's either a design or QC issue. There is another type with a bull-nose that doesn't use O-rings, that is reported to be much better. I don't know if it is possible to buy just the part concerned but you can pick the whole assembly up for $20-$30 on Smelly Express and probably fleaBay.

 

[Bigragu]

I bought that same exact set up, Franklink, and mine also would not hold air. The way the end comes back on the tip to create the front edge groove for the o ring, it has a rough sharp edge to it, and every time you insert it into your tank and bottom the end tip in, it’ll cut the o ring. Mine was not only sharp, but came distorted.

Hopefully Centercut pipes in because he had linked me to the one he buys from, and it came with the white o rings. The tips of the probe were better made, except the tightening wasn’t a hand tighten but a wrench tighten. 

What I ended up doing, is sourcing another probe set up from airtanksplus.com and swapped that into the already purchased set up, rather than buy a whole new fill assembly. No more cut o rings! 

https://airtanksplus.com/product/scba-hand-tight-fill-adapter/



or you can just purchase the elite set up called the Stikboy from ATP and be done with it. Really a nice set up and comes in a compact case. I only offer that suggestion cause the one thing I dislike about that one we bought, is I shoot tethered a lot, and that hose is not only short at 24”, it’s bulky and doesn’t “flex” easily, if you know what I mean. It’s as if that hose is too big a diameter for what’s needed, and too stiff. Anymore all I use that one from eBay is to do a quick top off to a gun, and that is all. For tethering or if I plan on shooting for a few hours, I use the Stikboy as its much easier to use, and I don’t feel like I’m using a garden hose to hook up to my gun, lol. 



https://airtanksplus.com/product/stikboy-pcp-fill-adapter/

 

[Jshepherd70]

http://www.mcmaster.com/1196n73

Part# 1196N73 Was close enough to work for me. The original one failed almost instantly. 

 

[Franklink]

Just wanted to thank all you guys for the input. 

I ended up ordering the Stik Boy. I have their splitter and have been quite happy with it. 

I was also able to get the 2x7.5mm orings to hold air with the Chinese fill station after realizing that too tight was cutting the oring, and too loose was letting it leak. VERY small window of the appropriate tightness. So narrow of a window that it's a pain in the butt, which makes me not regret ordering the new fill station.

 

[Bigragu]

I know it costs way more than the overseas fill stations, but as you use it, you will realize the investment was well worth it. Just the fact it’s so compact, and comes with its own case, yeah, I’d buy it again. 

Its not shown on his web page yet, but email Gene at ATP and pick up his new special thread seal tape for threaded fittings. Some of the pcp fittings I bought from him, I noticed had this red tape on the threads. I asked him about it, and he said it’ll hold HPA back from leaks, period. Well, I told myself my white Teflon and yellow Teflon gas tape from Home Depot should be good enough- wrong! I have a test gage I use when checking the readings on the hatsan lightning compressor, and have it rigged with a QD adapter. The other day while pressurizing up the Lightning, I saw the digital gage pressure dropping. Yep, it was that yellow tape on the threads of my adapter to the gage. It used to hold HPA, but after time it failed.

 

[Centercut]

I looked on eBay and the one I have (and have bought at least 20 of them) is no longer listed. It’s the one with the white delrin tip, NOT the orange.