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-   -   Oxygen refills? (https://vansairforce.net/community/showthread.php?t=150617)

RV6_flyer 06-21-2017 07:40 AM

Quote:

Originally Posted by Plummit (Post 1181977)
Same stuff. There is no difference.

-Marc

You are correct. Others have a hard time believing us when we tell them that.

Here is an article written years ago with the facts.

mbauer 06-21-2017 08:44 AM

Quote:

Originally Posted by BruceP (Post 1181940)

One of the places I visited yesterday said that medical/aviation oxygen is "dryer" than oxygen used for welding and they didn't have that. That's when they suggested going to the medical supply place. Do any of you know if there is a difference in medical/aviation oxygen? And if so, is it significant enough to worry about it? I'm guessing no given some of the responses on this thread.

Like has been stated, both are filled from liquid oxygen, only difference is the aviator is then checked for moisture. Just an additional step. No difference other than one more step.

Best regards,
Mike Bauer

Dugaru 06-21-2017 10:28 AM

Also my experience. I was AMAZED how much better I felt after flying with O2 even at low altitudes. For those who haven't tried it, it's well worth a shot.

Quote:

Originally Posted by rzbill (Post 1181959)
It was not a level that I would have expected oxygen to make me feel better. It did.


krw5927 06-21-2017 11:16 AM

Quote:

Originally Posted by bret (Post 1181988)
Hum...interesting, I would have thought you could get more than that from the one 251 tank? I can see why the cascade fill method would work better than one tank. Thanks for sharing this info.

Unfortunately the only thing that's useful for transfilling is pressure. Welders can use nearly all the O2 in the tank because they only need 10 PSI or so. But for transfilling, a bulk tank 3/4 full in terms of cubic feet remaining is nearly useless.

Some folks get 2 tanks just for this purpose. Bulk fill off the emptier tank, then top up to full pressure with the fuller one. Makes them both last longer than they otherwise would individually.

Timberwolf 06-22-2017 06:34 AM

Saw this thread which peaked my interest as my rv6 used to have an oxygen system that a PO uninstalled somewhere along the way. I looked on Craigslist just for the heck of it and was able to pick up a brand new 2 place 13 cu ft Aerox system for $100. Talk about a good find.

As for the refilling part of the thread, I was originally looking on Craigslist for one of the home refilling stations. I plan on keeping an eye out but for now will just have my MX guys fill it when needed.

swordtail 06-22-2017 07:21 AM

I forgot to mention that breathing welders o2 makes you a better welder also! Just a added side benefit.

BillL 06-22-2017 07:44 AM

Quote:

Originally Posted by krw5927 (Post 1182039)
Unfortunately the only thing that's useful for transfilling is pressure. Welders can use nearly all the O2 in the tank because they only need 10 PSI or so. But for transfilling, a bulk tank 3/4 full in terms of cubic feet remaining is nearly useless.

Some folks get 2 tanks just for this purpose. Bulk fill off the emptier tank, then top up to full pressure with the fuller one. Makes them both last longer than they otherwise would individually.

Yep - developed a spread sheet for this. Starting with full 251 tanks (K?), one tank would yield 5 fills (22 cf, JD) if it was at 300 psi before filling. With two K tanks cascading, one would get 15 fills before dropping below 1500 psi on filled tank.

I question getting a proper trans fill hardware manifold for $100 and would like to see the diagram and parts list. I did the economics for a $30 fill and with $450 for trans fill hardware, one K tank, it would take 12 fills (with mileage cost) to pay off the investment. It takes about 20 with 2 K tanks.

Yes, the cost per fill is way low, so payback in calendar time will depend on how much one uses/fills the tanks. It might be better just to get two flight tanks, and use each one down to the bottom.

The convenience of always having an 80% full flight tank anytime for TO is also to be considered, not just the cost per fill. A few friends at an airport would easily push a 3 tank cascade into reality in terms of cost and convenience. If you could get them to pay - they are pilots.

In case you wanted to get the last psi from the K tank and fully fill the flight tank there is a compressor for that. I got a quote for$5k. Payoff is a bit longer. Conclusion - cascade with more tanks is still way more cost effective.

So what am I doing - finishing my plane. Then get make the O2 refill decision.

RV7Guy 06-22-2017 08:01 AM

Fire Departments
 
This has not been mentioned. Do you know anybody with the local Fire Department? Seems everyone knows a fire fighter. Many have a cascading fill stations. Stop by and see if they do and see if they will fill your tank. Many will do it as "training."

I fly medical helicopters. We were based at a fire department that had a cascade system. They taught me how to use it. I filled my D bottle several times a year.

As mentioned, check with your doctor and get a prescription for O2. Then a medical supply will be your next best option. FBO's are ridiculous on their prices!!

jrs14855 06-22-2017 09:05 AM

O2
 
A 2 bottle cascade only requires a simple shutoff valve and T fitting and a short hose. If you have several friends to share the cost get a two bottle or more cascade with the largest bottles.

climberrn 06-22-2017 10:21 AM

O2 fill list
 
Would sure be nice if there was a location we could post a list of cheap O2 refills across the country. Anyone at CXP and we are home, shoot me a message if you want a fill.


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