Oxygen system - Make your own.

I decided I wanted an o2 system after enjoying flying high and crossing the the US and Canada. Looked into buying a ready to go one and found it a nightmare, even just getting it refilled in Canada is a battle if they know its for aviation. (a good two place d size would have set me back $500 to $800)

SO, figured I would make my own and learn how to not only build one but also be set up to get cheap refills and not have to get into the certifying the tank etc costs. Lots of good info here in the archives to help.

Here is what I got and the costs. I am 100% happy but am certainly open to ideas or improvements.

Chad therapeutics oxymizer cannulas $20 each x2
New pediatric low flow regulator with 0-4lpm dial $22
Ingen Tech Oxyview flow meters 2 x $12
1/4 ball valve to isolate copilot side if flying solo $11
D size alum tank (got medical prescrip) so tank annual rental and full of 02 was $55, they even threw in a nice carry bag. Refills are $25 each

So, a two man, D size low flow system, with meter, flow verifiers etc cost me $150, 02 included. Good deal!
Refills are $25 a time, you just walk into the medical place and give them the old and they hand you a new cyclinder. Simple.
Also, I did go to walmart prior to last big trip and for $32 got a very nice pulse ox meter. So for $180, if you are looking for a good 02 system. Here you go.

I did almost exactly the same thing, only found it better to buy a bottle down here, got me a "Jumbo D" size with fresh hydro static test for $50.
To get it filled in the US you MUST produce a medical prescription since it is a medical oxy bottle, upon which they fill it with welding oxygen for you, my Doc had no problems giving me one. Go figure.

Don

Thats is the kind of headache I found too. Nobody wants to fill the o2, or if they do they want $75. So getting the medical deal was the right path. Doc gave a prescrip, no issue. Dont tell the 02 firm its for flying, they get goofy.

I wanted to own a tank, but unless you go with your own transfil station...no way to refill. Silly. But...finally got it done and it took a lot of work, so figured I would post to see if it helped others get one built.

Use caution with the script because the FAA might want to know someday why you are on supplemental oxygen..... I think I will get my wife to ask her doc for one!

Anybody ever try claiming the oxygen tank is for your exotic fish aquarium and getting it refilled that way?

Script

In Canada, there are special Docs who do our aviation medical. A call to him and trip in with a request for a script was fine. Just tell them you are planning on doing some high alt flying...they would much rather you be safe as they all know about hypoxia. No worries at all.

Now the 02 company lady in their front office sales dept is terrified the tank will blow up as soon as I take off. When I told her a can of pop does ok, she just looked at me. Seriously...her concern was that the 02 cylinder would blow up. What the point in even starting the conversation?

As for FAA or our equivalent (transport canada) they would have no issue at all with a pilot having supplemental 02.

I don't get the need for a script -- must be a Canadian thing. I've read a number of posts here, on AOPA, and on POA about DIY O2 set-ups and it would seem most simply buy a tank and take it to the local welding O2 supplier (who probably also supplies the local medical and aviation O2 as it all comes from the same LOX tank). Some even go to dive shops.

The only issue I ever recall reading about is having the right connections on the bottle in order to do the transfill.

Typical scuba tanks are filled with compressed air...not oxygen.

I argued with the supplier, who also fills my welding OX tanks. He agreed that it was the same ox and a silly requirement, but blamed Obama for the need for a prescription to fill the bottle. An easy way out would be to get one of the Harbor freight Oxy bottles and just fill it as a welding tank. I think they charged me $45 to fill my Jumbo D tank.

Auburntsts said:

I don't get the need for a script -- must be a Canadian thing. I've read a number of posts here, on AOPA, and on POA about DIY O2 set-ups and it would seem most simply buy a tank and take it to the local welding O2 supplier (who probably also supplies the local medical and aviation O2 as it all comes from the same LOX tank). Some even go to dive shops.

The only issue I ever recall reading about is having the right connections on the bottle in order to do the transfill.

Click to expand...

Medical O2 in the US is a pain.

I use O2 a lot for Scuba Diving. While it isn't used for standard recreational diving, it is used frequently for decompression diving (it will kill you deeper than 20 ft).

If you are in an area that has a lot of technical diving. I.e. a lot of coastal areas, Florida (especially northern Florida), great lakes, etc. There are likely a number of dive shops that pump oxygen.

If you have such a shop locally, they will most likely be quite happy to sell you oxygen at about $.20 - $.40 a cubic foot. I.e. the small bottles you are likely using in your plane would cost you well under $15 to fill from empty.

The only possible issue, would be if they have the right adapters to fill medical grade tanks. However, for the price difference, if might be worth buying your own.

Another option would be to buy your own. I pay less than $20 for a K bottle (300 cubic foot) of Oxygen. You would also need fill whips, etc. to transfill into the bottles you are using in the plane.

One word of caution. Please be very careful playing with high pressure oxygen. I had a friend wind up with burns over 80% of his body due to a HP Oxygen fire from a tank...

-Dan

I did almost the same thing. I get mine filled at a welding supply store and I tell them its for a live bait well in a boat. 7$ per fill.
bought the tank used for 50$.

I get mine filled from a medical oxygen suppy company.
Costs $15 for the D size.
I just told them it was for aviation and they had me fill out an affidavit with me declaring aviation use.
They keep it on file and no questions asked whenever I get a refill.

Those who refill successfully with med/weld suppliers do you guys have this type of fitting?

I flew with an almost identical system that Rick is using, for four years. It is inexpensive and works fine. The problem I had is tank size. With the rocket I just do not have a lot of room for a larger tank. The D size tank is ok for flight levels in the 12K range on your average out and back cross country flight with two people but when I started flying in the 15 to 17K range it just was not large enough. Getting a medical bottle filled at an airport en route is just not practical. Getting any bottle filled while traveling probably means going to a larger full service airport and that would not only add to the O2 costs but usually adds a buck to the price of a gallon of fuel as well.
This year I bit the bullet and purchased the mountain high system and it has at least doubled how long two people can fly with a D bottle in my plane. As far as cross border issues, I just ordered the system and Fedex delivered it, I do not remember any problems.
I am fortunate to have a friendly welding shop that has given me a life time of refills for a one time donation of $20 to their coffee pot! (It also helps that I have spent a few bucks there as a customer over the last 30 years)

Around the Twin Cities, I know several people (including me), who pool money, buy a big tank of O2, and then fill the bottles off the tank.

Oxygen systems

A couple other thoughts on oxygen systems.

Be careful to not get oils on anything that will be in the presence of pure oxygen. Grease and oils can spontaneously combust in an environment of pure O2. Clean your tools that you use to assemble a system.

Buy a Oxysaver canula. You'll use a fraction of the oxygen flow. The canula looks like a bad mustache. The reservoir under your nose fills with O2 while you exhale and you get a bolus of pure O2 when you inhale. That first part of the inhale goes deepest into the lungs so that bolus is very useful. It costs about $30 for the canula, but you can dial down your usage significantly. My flow meter has two scales - one for regular canula and one for oxysaver - and a needle valve to adjust.

@grenwis:

The picture in the first post shows a cannula that looks like the Oxsaver cannulae that i've seen in other friends' RV's on my field. Rick called it an Oxymizer cannula. Do you agree it looks the same, or at the very least does it look like it should work the same way?

@Rick:

Does the regulator have enough fine adjustment control to really save lots of air with the Oxymizer cannulae? I'm just curious how hard it would be to get fine control over the O2 while in flight, without wasting too much along the way.

Snowflake

I specifically listed them as oxymizer cannulas. Chad therepeutics makes the best ones. Named them and posted pics of them, best i can do.

Further a pediatric regulator allows you to make all sorts of small adjustments on the dial. down to .125 lpm. There is a little chart floating around here that you can use as bit of a guide for o2 flow needs at various alts, and it shows standard o2 needs or oxymizer flow needs. If i can dig it out, will post.

Using the D tanks and these cannulas, you get a LOT of flying. Seems like the right mix for my needs. I love the fancy on demand systems but dont wish to spend the big$$ for my use.

RickWoodall said:

....
Further a pediatric regulator allows you to make all sorts of small adjustments on the dial. down to .125 lpm. There is a little chart floating around here that you can use as bit of a guide for o2 flow needs at various alts, and it shows standard o2 needs or oxymizer flow needs. If i can dig it out, will post.
.....

Click to expand...

Instead of a chart you could use one of these dual scale flowmeters to set the flow rate vs. altitude -



http://www.chiefaircraft.com/ao-glow-meter.html

Individuals vary a lot (age, smoker, etc.). Now that the cost has come down I really recommend getting a pulse oxymeter, so you can customize the flow setting you need on every flight. BTW, if you get bored, you can "play" with the pulse oxymeter. e.g., you can see that rapid shallow breathing will cause your O2 saturation level to drop, while slow deep breathing will cause it to rise, breathing thru your mouth will cause it to drop, ...

Like D-Day from Animal House, I've been working with oxygen-acetylene since I was a teenager. However, welding safety isn't quite the same as oxygen system design. I had no idea how ignorant I was until previous posts motivated some reading. Turns out there are several not-so-obvious ways to cook yourself, lose an arm, or worse......for example, just opening a valve too quickly under the wrong circumstances.

Anyway, before plumbing your airplane or rigging an oxygen refill system, Google some search word combinations. There are NASA papers worth reading, industry publications, even a gory video or two.