Hangar Project - Oxygen Filling Setup

[JoshK]

2 hours ago, wombat said:

You have an airgas store 6 miles from the airport and they do provide ABO.

Rent/lease only for 200 and 300ft size tanks.  

 

I should have been more clear:  Keen is very local (under 2 miles) to my business and rents only for sizes over 80ft.  Airgas doesn't answer their phone but when I walked in they wanted a higher rental rate and larger deposit than Keen, they only rent for sizes over 125ft.  They're about the same distance from the airport but much farther from my business address.  Both will swap for you but they won't take a tank on swap that needs hydro without billing you for the hydro cost.  Cost of a fill from Keen is $25 for a 200 or 300 ft, Airgas was similarly priced for 200 and was $10 more for 300ft.  

 

Wilson Products will fill while you wait if you want, they sell 200/250/300ft and they're a 3 hour drive round trip.  Fills were expensive, about $90.

 

For now I'm just going to rent the 3 tanks and see how things go.  I can always buy tanks over time and drop off the rentals as I acrue my own. 

[JimB]

I do get the CB pilot and aircraft ownership thing, but I have to just say this is a really bad idea.... I have seen what an aircraft looks like up close and personal after a fire started by someone filling O2 and those people had very specific training on what they were doing.

[N201MKTurbo]

9 minutes ago, JimB said:

I do get the CB pilot and aircraft ownership thing, but I have to just say this is a really bad idea.... I have seen what an aircraft looks like up close and personal after a fire started by someone filling O2 and those people had very specific training on what they were doing.

Just because you have been trained, doesn't necessarily mean you follow the training. In the limited time I've spent in airline maintenance facilities, I've seen some poor work done. Especially during labor disputes. I haven't spent much time lately, but back in the 80s I worked on computers for the airlines and spent a lot of time there.

[wombat]

So weird.   My local shop (a distributor for Norco) and my local praxiar supplier don't even pay attention to the hydrostatic test dates on the cylinders I bring them.   As long as it's a cylinder I own (either marked as an owner cylinder, or in their records as one that I own because I got it on exchange from them) and it's not damaged they'll just take it into their inventory and provide me with a full one of the same size for their 'exchange' rate.

 

Honestly though, the expense of this is so low compared to other things that it's hardly worth bothering with.    You could track the hydrostatic test dates on your own and return them before they'll charge you for it.  But that's just another currency to track.

Personally, I'm not going to get a cascade system and not track hydrostatic test dates.  I'll just get one bottle and exchange it at like 1,000 PSI.    I don't usually need my onboard bottle to have really high pressure.  If I need more than 12 person-hours of O2 at once (1,000 PSI at 20,000 MSL with the 115 Ft^3 onboard tank)) I'll spend an extra $55 and get it exchanged before the flight so I can refill it to a higher pressure.   In order to need more than 12 person-hours, I'd need to either fly 12 hours (20 GPH * 12 * $6.50 = $1,560 in gas) or 6 hours with two people ($780 in gas)  or fly with three or more people, which is going to be so limiting in weight that I won't have the fuel to make it very far anyway, so I probably wouldn't climb up very high.

A 'full' tank (if I assume 20,000) at 1,800 PSI gives me 20+ person hours of oxygen, and if I get that many hours at that altitude in a year I'll be pretty pleased with myself.    But a single hangar tank will fill it to that at least once, plus to lower pressures a couple of times.   If I manage to spend $120/year on Oxygen (Other than initial purchase), that will be quite the thing.    And if I spend that much, I'll be well clear of any hydrostatic testing requirements.  If I spend much less, that will just be even cheaper.

 

[JimB]

30 minutes ago, N201MKTurbo said:

Just because you have been trained, doesn't necessarily mean you follow the training. In the limited time I've spent in airline maintenance facilities, I've seen some poor work done. Especially during labor disputes. I haven't spent much time lately, but back in the 80s I worked on computers for the airlines and spent a lot of time there.

Hey! I get it! But if you haven't been trained at all then just watch a YouTube video I guess. You will figure it out eventually. And you realize not all those pictures were airlines? One was a P3

[N201MKTurbo]

11 minutes ago, JimB said:

Hey! I get it! But if you haven't been trained at all then just watch a YouTube video I guess. You will figure it out eventually. And you realize not all those pictures were airlines? One was a P3

I have spent a day in the Navy maintenance facility at North Island where they rebuild FA-18s. It had the same vibe as an airline maintenance facility.

[Z W]

3 hours ago, JimB said:

I do get the CB pilot and aircraft ownership thing, but I have to just say this is a really bad idea.... I have seen what an aircraft looks like up close and personal after a fire started by someone filling O2 and those people had very specific training on what they were doing.

Wait until you find out what they let any untrained kid fill up the wings with...

Just kidding around.  I grew up using an oxygen/acetylene torch to melt holes in steel in an average garage.  There are risks involved, and they should be considered and treated appropriately.  They may not be for everyone.  Your experience may vary.  If you don't already have a fire extinguisher easily accessible in your garage and in your hangar, it's a good idea for lots of reasons, this included.

Edited September 13, 2023 by Z W

[JoshK]

So weird.   My local shop (a distributor for Norco) and my local praxiar supplier don't even pay attention to the hydrostatic test dates on the cylinders I bring them.   As long as it's a cylinder I own (either marked as an owner cylinder, or in their records as one that I own because I got it on exchange from them) and it's not damaged they'll just take it into their inventory and provide me with a full one of the same size for their 'exchange' rate.
 
Honestly though, the expense of this is so low compared to other things that it's hardly worth bothering with.    You could track the hydrostatic test dates on your own and return them before they'll charge you for it.  But that's just another currency to track.
Personally, I'm not going to get a cascade system and not track hydrostatic test dates.  I'll just get one bottle and exchange it at like 1,000 PSI.    I don't usually need my onboard bottle to have really high pressure.  If I need more than 12 person-hours of O2 at once (1,000 PSI at 20,000 MSL with the 115 Ft^3 onboard tank)) I'll spend an extra $55 and get it exchanged before the flight so I can refill it to a higher pressure.   In order to need more than 12 person-hours, I'd need to either fly 12 hours (20 GPH * 12 * $6.50 = $1,560 in gas) or 6 hours with two people ($780 in gas)  or fly with three or more people, which is going to be so limiting in weight that I won't have the fuel to make it very far anyway, so I probably wouldn't climb up very high.
A 'full' tank (if I assume 20,000) at 1,800 PSI gives me 20+ person hours of oxygen, and if I get that many hours at that altitude in a year I'll be pretty pleased with myself.    But a single hangar tank will fill it to that at least once, plus to lower pressures a couple of times.   If I manage to spend $120/year on Oxygen (Other than initial purchase), that will be quite the thing.    And if I spend that much, I'll be well clear of any hydrostatic testing requirements.  If I spend much less, that will just be even cheaper.
 

Excellent points. All in all the cost of the oxygen system in hangar is still pretty low whether we are renting or buying. Compared to paying for fills at another FBO I will have the annual rental amortized in 1 fill and the overall cost of the other extemporaneous pieces amortized in 2 more since I didn’t buy the tanks.


Sent from my iPhone using Tapatalk

[GeeBee]

On 9/13/2023 at 12:57 PM, JimB said:

I do get the CB pilot and aircraft ownership thing, but I have to just say this is a really bad idea.... I have seen what an aircraft looks like up close and personal after a fire started by someone filling O2 and those people had very specific training on what they were doing.

Add Delta 1558 at KSLC to that list. Very close to having fatalities. In that case they were not filling but swapping cylinders. The fire started after the bottle swap and the mechanic leaving the compartment. Oxygen seems "benign" because we breathe it, but it is buffered by nitrogen. Pure O2 is a dragon in a bottle. Treat it like that fact.

https://www.accidents.app/summaries/accident/20001213X29575

[Pinecone]

On 9/13/2023 at 1:16 PM, wombat said:

Personally, I'm not going to get a cascade system and not track hydrostatic test dates.  I'll just get one bottle and exchange it at like 1,000 PSI.    I don't usually need my onboard bottle to have really high pressure.  If I need more than 12 person-hours of O2 at once (1,000 PSI at 20,000 MSL with the 115 Ft^3 onboard tank)) I'll spend an extra $55 and get it exchanged before the flight so I can refill it to a higher pressure.   In order to need more than 12 person-hours, I'd need to either fly 12 hours (20 GPH * 12 * $6.50 = $1,560 in gas) or 6 hours with two people ($780 in gas)  or fly with three or more people, which is going to be so limiting in weight that I won't have the fuel to make it very far anyway, so I probably wouldn't climb up very high.

That may be more often than you think.

How big is the bottle in your plane?  Mine is 115 cf.  A 200 cf gas cylinder is 9 inches by 51 inches.  A 115 cf Kevlar cylinder is 9.1 inches by 31 inches.   So a rough calc says you will end up with 1250 psi if the aircraft cylinder is empty.  You next fill would be under 800 psi.

[A64Pilot]

The issue with O2 safety is well anything that will burn, but usually liquid hydrocarbons like an oil or grease etc. even natural skin oil so you should wash your hands before touching anything that will be exposed to high pressure O2, it’s the pressure that makes it dangerous or if it weren’t then our O2 cannula’s and mask would occasionally catch fire.

If any are smokers take in a breath of pure O2 then blow it out of a cigarette, it’s impressive and scary because some smoke when they are on O2.

I watched a friend who worked at a cave dive shop I used get up from eating lunch, wipe his hands off good and disconnect an O2 bottle from the Haskal, his hand got burnt, the tiny bit of grease from the fried chicken was all it took.

1 drop of oil can cause an explosion and if it was on the threads / valve etc the bottle can burst and of course it’s a bomb.

To “O2” clean fittings, interior of tanks, valves etc. we used a solution of simple green, it’s apparently a very good degreaser, valve pieces etc were cleaned in an ultrasonic, tanks were tumbled like a rock polisher with special triangular rock looking things and simple green solution with distilled water.

If your diligent with cleanliness to be honest you will be safer than any FBO, I’ve never seen any welder or FBO etc follow O2 clean guidelines, most either don’t know or don’t believe it.

When I was a welder I knew not to put oil on any threads but that was about it, it wasn’t until I started tech diving that I learned the dangers.

It’s actually amazing that there aren’t more accidents

[A64Pilot]

I knew these people well, it was Bill Renniker’s shop, he was a Retired pipe fitter from somewhere up North and moved to Fl for cave diving, you had to see his shop, the compressors, cascades etc were a master piece, he really knew his stuff, so it was really surprising that this incident happened at Bills shop. Bill was one of the founders of cave diving, didn’t get all the press, but he didn’t die diving either.

https://www.luxfercylinders.com/news/cylinder-incident-in-luraville-florida

[wombat]

3 hours ago, Pinecone said:

That may be more often than you think.

How big is the bottle in your plane?  Mine is 115 cf.  A 200 cf gas cylinder is 9 inches by 51 inches.  A 115 cf Kevlar cylinder is 9.1 inches by 31 inches.   So a rough calc says you will end up with 1250 psi if the aircraft cylinder is empty.  You next fill would be under 800 psi.

Good point, that filling from empty will take a lot of the O2 out of the source bottle to begin with.  On the other hand, I'll never take the pressure down to zero in the plane's tank.    

 

Regardless, I think the cost will be lower if I have my own bottle, low enough I won't try to conserve oxygen to save on cost.And I expect the convenience to be a lot higher.

[N201MKTurbo]

A tiny bit of oil cannot make a very big explosion. There is only so much oil to react. If it does react, it will probably make a very small pop and not hurt anything. By the time you get to a few hundred PSI, everything that is going to react has reacted. The big danger is having enough fuel to heat the system components enough to react. It can set the system on fire, think cutting torch. If the system starts burning, your best bet is to turn the feed supply off if you can safely get to it, if you can't, just run like hell.

[JoshK]

Following back on this now that everything is here for a test fill

I started with a bone empty 15ft portable cylinder and empty 115ft tank in the Rocket

The links to the whip and adapter that are in this thread work perfectly and the parts arrived in about 10 days all total.

I used 200ft Oxygen cylinders for the first fill, I will swap to 300’s when I swap them (same price, local place didnt carry 300’s so they’re special order)

First stage starting at 2300 psi brought the A/C tank to 1400psi. Then 1400 in the first stage brought the 15ft portable up to 1150ish

Second stage starting at 2300 brought the A/C to 1750 where I stopped it. Bottle still has 2000 in it. I topped the portable up to 1750 as well and near as I can read the gauge I think stage 2 is 1850-1900

I didn’t touch stage 3 yet

The system is kludgy right now, I have to make the time to build a rolling rack. Bottles are currently stored laying down and chocked into a corner. When in use I stand one up and strap it to a hand truck to stabilize it while filling.

I will refine more as I fill more however I think the following is my go forward:

Get the 300ft bottles to start
A single bottle isn’t bad but 2 is better, looks like 3 will be optimal for a hangar setup for a single airplane.

The Aviation adapter for CGA540 to Scott 9/16-18 is substantially more expensive than buying the fittings off Amazon and assembling yourself. No surprise, I just didn’t know the fittings were standard so I pod the $205 or so for an aviation one instead of a welding supply one. I am looking for an off the shelf solution now online, I can find one that comes preassembled I will post it.

Other than that, everything else is off the shelf sourced from Amazon. This is easy. Fill slow, be clean and careful, and you can be independent on your oxygen.


Sent from my iPhone using Tapatalk

[Pinecone]

FYI, if a tank is really empty (as in ZERO pressure), it should not just be filled.  It should be cleaned and purged.

[kortopates]

FYI, if a tank is really empty (as in ZERO pressure), it should not just be filled.  It should be cleaned and purged.

True, it’s a requirement too.


Sent from my iPhone using Tapatalk

[JoshK]

6 hours ago, Pinecone said:

FYI, if a tank is really empty (as in ZERO pressure), it should not just be filled.  It should be cleaned and purged.

Excellent point.  The new portable came oxygen clean and ready for fill.

[Mac80]

Having issues to get portable O2 tank  filled or inspected. Going to work through this.

Inflation hit my filling station. Was free as courtesy years ago. Next $20 for 20 cubic feet, then $40 per bottle now $128. Geez 

I have some large filling O2 tanks available but  they are 1200 miles from home base.

Looking at Mountain high site their cascade equipment is expensive but I do like their stuff. Their TR 95 cylinder transfer system and inter-coupling kit CIC-540  looks like good quality.

 

[N201MKTurbo]

1 hour ago, Mac80 said:

Having issues to get portable O2 tank  filled or inspected. Going to work through this.

Inflation hit my filling station. Was free as courtesy years ago. Next $20 for 20 cubic feet, then $40 per bottle now $128. Geez 

I have some large filling O2 tanks available but  they are 1200 miles from home base.

Looking at Mountain high site their cascade equipment is expensive but I do like their stuff. Their TR 95 cylinder transfer system and inter-coupling kit CIC-540  looks like good quality.

 

Why are you having trouble getting your portable cylinders hydro tested? I take mine to the local cylinder shop, they give me a ticket and say “it will be done day after tomorrow”.

[Mac80]

I was trying to go through scuba shop and not sure why they were not more responsive I had no idea were to take it.

FBO was not assisting me or did not where to go.

Air gas distribution center has to send them out for inspection and filling. Gave a long time frame to service. They also take some time to inspections and to get oxygen  will only do it for truck load. They have to fill medical oxygen in St. Louis.

I finally asked the scuba shop were they we going and found a shop that will test my portable for $45 and do a large cylinder for $100. They mostly do fire extinguishers, fire fighting equipment, and few scuba tanks. Did not see any other tanks for planes. 

Air gas said they will fill tanks I own for my own use. Have not got a price yet. At least it seems doable. 

I have been relying on others and was ignorant of the process.

My second possible source is friend does a lot welding and machine type work for me. He has many large tanks in his shop and he is mostly retired.
 

 

Edited October 30, 2023 by Mac80
Spell check

[N201MKTurbo]

1 hour ago, Mac80 said:

I was trying to go through scuba shop and not sure why they were not more responsive I had no idea were to take it.

FBO was not assisting me or did not where to go.

Air gas distribution center has to send them out for inspection and filling. Gave a long time frame to service. They also take some time to inspections and to get oxygen  will only do it for truck load. They have to fill medical oxygen in St. Louis.

I finally asked the scuba shop were they we going and found a shop that will test my portable for $45 and do a large cylinder for $100. They mostly do fire extinguishers, fire fighting equipment, and few scuba tanks. Did not see any other tanks for planes. 

Air gas said they will fill tanks I own for my own use. Have not got a price yet. At least it seems doable. 

I have been relying on others and was ignorant of the process.

My second possible source is friend does a lot welding and machine type work for me. He has many large tanks in his shop and he is mostly retired.
 

 

$45 for a hydro test these days, is about right. I would take it to that shop. 
 

Or just buy the metal stamps….

[wombat]

I finally went ahead and made an order for much of this stuff today.

I got the CGA540 female to CGA540 female fill adapter from amazon for $100:  https://www.amazon.com/gp/product/B09TCDBFP4/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

 

And I got a CGA-540 Male to Scott 9/16-18 Male from MH Oxygen for $105  (Cheaper than Aircraft Spruce)

And I also got a CGA-540 Male to CGA-540 Male from MH oxygen for $50 so I can refill my portable Aerox tank for the Cessna 182.

 

We'll see how this all goes.   I've got an oxygen tank for my acetylene torch, so I figure I'll just turn that one in and replace it with a new one filled with ABO that I know I can use at the hangar.

[skykrawler]

How are you guys getting your onboard tanks hydro tested and valves overhauled?

 

[wombat]

Have not had to do it yet.     I suspect I will do these things on condition, if something happens.

My aviation tank was installed new in late 2022, so I've got a while yet.