Oxygen system fittings

[NealRomeoGolf]

I am doing my best attempt at creating my own oxygen system since I now have an airplane capable of 18k plus. I've followed the Doc Bruce guide on DIY oxygen system (here), but I'm stuck on how to get the oxygen hose connected to the Skyox regulator. "Buy an 8 foot piece of 80 PSI hose and the appropriate CGA 540 fittings" The problem is I'm too stupid to know what "the appropriate fittings are." Can someone point me in the right direction? The skyox screws onto a CGA540 fitting. I get that. Regulator is here. The hose I bought is here. Now I need a fitting that can go from the hose to the Skyox. I look for CGA540 to DISS fittings but can't find anything. I am not a mechanical person so I'm sure I'm looking for the wrong terms. Help.

 

[FORANE]

I am doing my best attempt at creating my own oxygen system since I now have an airplane capable of 18k plus. I've followed the Doc Bruce guide on DIY oxygen system (here), but I'm stuck on how to get the oxygen hose connected to the Skyox regulator. "Buy an 8 foot piece of 80 PSI hose and the appropriate CGA 540 fittings" The problem is I'm too stupid to know what "the appropriate fittings are." Can someone point me in the right direction? The skyox screws onto a CGA540 fitting. I get that. Regulator is here. The hose I bought is here. Now I need a fitting that can go from the hose to the Skyox. I look for CGA540 to DISS fittings but can't find anything. I am not a mechanical person so I'm sure I'm looking for the wrong terms. Help.

Looking at that DB guide, it leaves some to be desired regarding details. It appears to describe a system with remote o2 cylinder. From your description it sounds like that is what you want. Understand a remote cylinder needs a pressure reduction regulator at the cylinder. I don't see that in your post; the skyox is located at the cockpit correct?

Your hose doesn't list any spec for psi limit. I would want to know that. In order to answer your question we would be well served to have pics of the pressure reducing regulator fitting at the cylinder or at least the type fitting. It would connect to your hose. Your hose would then connect to the skyox in cockpit, correct? Tank>pressure reducer regulator>hose>skyox>nasal cannulas...

You ask about the adapter between a cga540 and diss. I am not aware of any direct fitting that does that. You will likely need to find a diss>npt fitting and a cga540>npt fitting. https://www.ebay.com/itm/192537529241 https://www.ebay.com/itm/193831925950

Edited to add, I found a reducing regulator cga540 to diss here:

Oxygen Regulator

www.madamedical.com

My system uses small cylinders with regulator on cylinder described in my post here:
https://www.pilotsofamerica.com/com...refilling-an-oxygen-tank.128342/#post-2978888

Below is a picture of my large cylinder at home with a trans fill adapter connected to the small cylinder I keep in the cockpit.

Below is the regulator that attached to the small cylinder in my cockpit.

easy pulse 5 regulator Tested Excellent Condition | eBay

easy pulse 5 regulator Tested Excellent Condition.

www.ebay.com

 

[MountainDude]

My 2 cents: If I flew above 18K, where my life (and possibly others') depends on a reliable O2 supply, I would spend the extra few 100s to get a premade kit from a reliable source, like MountainHigh.

 

[Racerx]

Full disclosure...not familiar with medical Oxygen tanks or fittings. And haven't seen a sky ox regulator in person.

The cga540 is really a nipple with a nut that screws to the oxygen tank. The other end of is I believe 1/4" pipe thread that usually goes into a regulator. Looking at the good doc's instructions and what you've got. I think you're missing that first "step down" regulator.

However, I don't believe the step down regulator or the hose are actually necessary. Used in the way doc is describing you regulate the high pressure down prior to the sky ox and using the sky ox as a flow meter. But sky ox is calling for a cga 540 so that tells me it's capable of the high pressure and screws right to the tank.

I'd call sky ox to verify it can take the high pressure. Otherwise I believe the diss fitting can screw to the outlet "B" fitting on a normal torch regulator. Then you'd need 1/4" male npt to diss.

 

[NealRomeoGolf]

Full disclosure...not familiar with medical Oxygen tanks or fittings. And haven't seen a sky ox regulator in person.

The cga540 is really a nipple with a nut that screws to the oxygen tank. The other end of is I believe 1/4" pipe thread that usually goes into a regulator. Looking at the good doc's instructions and what you've got. I think you're missing that first "step down" regulator.

However, I don't believe the step down regulator or the hose are actually necessary. Used in the way doc is describing you regulate the high pressure down prior to the sky ox and using the sky ox as a flow meter. But sky ox is calling for a cga 540 so that tells me it's capable of the high pressure and screws right to the tank.

I'd call sky ox to verify it can take the high pressure. Otherwise I believe the diss fitting can screw to the outlet "B" fitting on a normal torch regulator. Then you'd need 1/4" male npt to diss.

The regulator that is on the bottle itself is similar (or equal) to this one. Isn't this the step down regulator? So it goes oxygen tank, regulator linked in this post, 8 foot hose linked in first post and then I need something to get from the hose to the Skyox regulator. The Skyox is for the oxygen to be on demand rather than just flowing all the time. The skyox is kept at the cockpit because you can change the flow rate based on altitude.

Does that help?

 

[Jim K]

Yeah, you're stepping pressure down at the bottle so you aren't running a 2000psi hose through the cabin. I would be concerned about the skyox working correctly at such "low" pressure, but I suppose it just looks to the skyox like the bottle is perpetually almost empty. Further, if @bbchien says it works, I believe it. My earlier comment about NPT being leak prone is probably incorrect, because as @Racerx mentions, the high pressure regulator uses NPT. I think the solution will be Skyox- CGA540->NPT- NPT coupling- NPT->DISS- hose. Those adapters are readily available. What I haven't been able to figure out is if DISS is the same as CGA 30.

 

[Racerx]

Got it. I believe the outlet on the regulator will be a 1/4" male npt on the regulator side. And a "b" on the hose side. I think you're hose can screw directly to that. Otherwise you'd need a diss male to 1/4" npt male. Which I think will be the same fitting you need going to the sky ox.

The inlet side of the linked regulator is the cga 540. That side that goes to the tank is the nipple. Side that goes to the regulator is just 1/4" npt...

It could be 5/16 npt. Pipe sizes always screw with me. You're looking for npt to diss. Not cga540.

Can also go to local weld shop and have them make an oxygen hose (if they don't have one premade) you know will connect to the regulator and get the same fitting that screws to the sky ox. And that's what I'd do. Cuz I'm lazy and my gas vendor stops in every Thursday.

Wrap some Teflon. Pressure up. Spray some soapy water.

 

[brcase]

I am doing my best attempt at creating my own oxygen system since I now have an airplane capable of 18k plus. I've followed the Doc Bruce guide on DIY oxygen system (here), but I'm stuck on how to get the oxygen hose connected to the Skyox regulator. "Buy an 8 foot piece of 80 PSI hose and the appropriate CGA 540 fittings" The problem is I'm too stupid to know what "the appropriate fittings are." Can someone point me in the right direction? The skyox screws onto a CGA540 fitting. I get that. Regulator is here. The hose I bought is here. Now I need a fitting that can go from the hose to the Skyox. I look for CGA540 to DISS fittings but can't find anything. I am not a mechanical person so I'm sure I'm looking for the wrong terms. Help.

Depends on how you want to set it up. From the regulator you showed I assume you want a two place system.
That regulator works best when you have the bottle within reach of you and you can set the altitude you like as well as turn it on and off at the bottle.
If that is what you want then forget the hose, and just buy the https://www.aerox.com/sky-ox-cannula-kit/ that goes with it, with the connector.

If you want a remote bottle I would recommend against using that regulator, It can be done with a CG-540 type hose (Female to Male), but it means you have a 2000psi o2 line running from the tank to the regulator.
instead use a regulator like this....https://www.aerox.com/400r2g-regulator-aerox-2-outlet-with-gauge/ (or pick the one with the number of outlets you want).
or
or

This reduces the pressure to about 20psi IIRC.. Then use a flowmeter like included in this kit https://www.aerox.com/4110-705-oxysaver-cannula-kit-with-needle-valve-at-fitting/
or https://www.mhoxygen.com/product-ca...ms/flowmeters-portable-constant-flow-systems/
or
if you need to add a vinyl tubbing to extend it that can easily be done with vinyl tubing and barbed push connectors


better plan is just spring for a Mountain High System pulse demand system, that will automatically adjust for you altitude and warn you if it doesn't detect you breathing the O2 and uses about 75% less O2 making your bottle last 75% longer.


Edit: if you want to fly about 18,000 then you need a Mask instead of a Cannula and a matching flowmeter for the mask for constant flow systems.


Brian
CFIIG/ASEL

 

[FORANE]

The regulator that is on the bottle itself is similar (or equal) to this one. Isn't this the step down regulator? So it goes oxygen tank, regulator linked in this post, 8 foot hose linked in first post and then I need something to get from the hose to the Skyox regulator. The Skyox is for the oxygen to be on demand rather than just flowing all the time. The skyox is kept at the cockpit because you can change the flow rate based on altitude.

Does that help?

Yeah, that's a step down regulator. I'm not familiar with the skyox system but I am familiar with pipeline oxygen and yes, 50 psi in the pipeline is typical.

Surely skyox has seen this before and has suggestions for connecting to a remote oxygen cylinder. Sans that, the npt fittings I linked in my earlier post would work.

You'll want to get familiar with oxygen safety. Read about cleanliness, petroleum, speed of valve opening, temperature, etc.

 

[AA5Bman]

This discussion is interesting to me as I have tried to do this (put together a DIY O2 system) and found it to be way harder and more expensive than I expected. Made me rethink the cost/value proposition of just buying a complete setup from one of the various aviation suppliers, which is ultimately what I did. I’d be curious to hear your report @NealRomeoGolf when it’s all said and done, in terms of whether it was worth it from a time and cost point of view.

I do have one thing to add to the topic that is often discussed: our business now supports a number of gas distributors (medical, welding, dry ice, etc). I was on site with one of our customers recently and asked the GM about the medical vs. welding oxygen question and whether or not it would be safe to breathe welding oxygen, and he reported that, as expected, it is the 100% exact same product and the only difference was which “papers” the oxygen comes with. I can’t remember the reason now, but he actually was of the opinion that the welding oxygen is probably actually cleaner, but unfortunately, I can’t remember why. Food for thought - if you have any concerns, worth asking your distributor if it’s all the same thing anyway!

 

[Racerx]

I do have one thing to add to the topic that is often discussed: our business now supports a number of gas distributors (medical, welding, dry ice, etc). I was on site with one of our customers recently and asked the GM about the medical vs. welding oxygen question and whether or not it would be safe to breathe welding oxygen, and he reported that, as expected, it is the 100% exact same product and the only difference was which “papers” the oxygen comes with. I can’t remember the reason now, but he actually was of the opinion that the welding oxygen is probably actually cleaner, but unfortunately, I can’t remember why. Food for thought - if you have any concerns, worth asking your distributor if it’s all the same thing anyway!

If I had to guess, I'd imagine it has to do with the moisture added for medical Oxygen, but that's done at the bedside now. If you go back 50 years we had different methods for bottling which led to different purities. To be able to torch we need 80% purity. All oxygen is bottled today using the liquefaction process and already has a purity that exceeds the needs for ABO, medical, and industrial uses. Just a matter of certification.

Oxygen is oxygen

Oxygen is oxygen is oxygen. There is a lot of misinformation out there about medical oxygen versus aviator breathing oxygen versus industrial-grade welding oxygen, but the bottom line is that is all three are the same.

www.aopa.org

 

[455 Bravo Uniform]

I use this to go from the aviation oxygen fill fitting (big supply tank) to my medical oxygen bottles for refills:

 

[455 Bravo Uniform]

You can find cheap used medical oxygen bottles like this for about $50 or less per bottle. Used regulators $5-20. The larger one in the pic below is a demand regulator. FB marketplace or Craigslist.

Nasal cannulas on Amazon. I think I got a 5 pack for a few bucks.

I need to figure out how to do a supply tank with regulators and line; I get mine filled at the FBO using my fitting in the post above (I travel with my adapter). Would love an Inogen instead…

 

[bbchien]

From McMaster-Carr's catalog......but just go to any welding shop; they'll have the hardware you need....