Building own o2 bank

[jonahfab]

After taking my gas blender class I now have the idea to build my own o2 bank so that I can fill my tanks with the needed o2 and then have them topped off at my lds with air to get the proper nitrox mix. Can anyone point in a direction where I could find plans or blueprints to accomplice this?

 

[Uncle Pug]

You don't really need anything other than a fill whip and two or three O2 tanks. (And of course you will need to O2 clean your tanks.)

The real issue will be whether or not you can get your LDS to top off the tanks with air and whether or not their compressor/filter system produces O2 compatible air. Taking a tank pre loaded with O2 to an unsupecting dive shop that is using an oil compresser and normal air filtration is a very bad idea.

 

[wreckchick]

I highly suggest getting Vance Harlow's The Oxygen Hacker's Companion before you do anything. It's an excellent read and will give you everything you need to know to blend your own gas.

Do take Pug's advice and check the air from your LDS before you start topping with it.

Rachel

 

[oly5050user]

After taking my gas blender class I now have the idea to build my own o2 bank so that I can fill my tanks with the needed o2 and then have them topped off at my lds with air to get the proper nitrox mix. Can anyone point in a direction where I could find plans or blueprints to accomplice this?

why not just let the lds pump your nitrox fill? I know that I would be reluctant to accept the risk to top off a tank that I know very little about..its one thing if you are ready to accept the risk by partial fill your tank with o2 and then use YOUR compressor/fill station to finish it--its another to ask a lds to take a chance and do it..

 

[jonahfab]

why not just let the lds pump your nitrox fill? I know that I would be reluctant to accept the risk to top off a tank that I know very little about..its one thing if you are ready to accept the risk by partial fill your tank with o2 and then use YOUR compressor/fill station to finish it--its another to ask a lds to take a chance and do it..

Well the idea would be to be able to dive nitrox cheaper, of course I'm just starting to research it so I don't know if it will really save me that much many right away, but am looking long term. The lds a go to does partial pressure fills already, so it would really just be me using my own o2 instead of theirs.

 

[Uncle Pug]

jonahfab, I think that if you cost it out you will find that you are not saving much if any and adding a layer of effort and complexity. Filter media cost $$ and your dive shop will probably need to charge you more for O2 compatible air than for regular air that has not been run through the extra filters.

When you add on the cost of the fill whip, the cost of leasing (or buying and maintaining) multiple bottles of O2 plus the cost of the O2 itself you will probably find that it isn't worth it.

One thing you might inquire about is a yearly subscription for nitrox. One of the local shops charges $400 per year/unlimited fills. This is somewhat low so it may cost more in your area if you can find a shop willing (and if you dive enough to make it work for you.)

I have my own fill station and continuously blend and bank nitrox. The convenience is a huge factor for me and the fill station has more than paid for itself. However if I were doing what you propose it would be an inconvenience as I would have to go through more steps than if I just went in and paid for a nitrox fill.

 

[pescador775]

Jonah, you can never predict what final pressure will be received at some LDS. Thus, "exact mixture" becomes moot. Wait a while. Read the "Hacker's Companion", wait some more. Continue to buy fills locally.Meanwhile, assess how much gas diving you are actually doing. Calculate the tangibles like a precision oxygen fill whip, and the other stuff mentioned by Pug. Also, consider the intangibles and hassle factors on both sides.

If you and your friends do a lot of diving, then renting O2 tanks may make sense. However, after a while you may get tired of partial pressure filling. For example, when refilling partly empty tanks you will have to consider whether dumping the old gas or calculating the percentages for a top off. PP filling is a SLOW process. Not hard to do but all the little stuff adds up in the intangibles side--as does the hassle of scheduling and running to a dive shop, not to mention the tangible problem of impulse shopping while there.

Look inward. Just what is your committment to diving? How old are you? What is your financial situation? Can you see yourself still diving 20 years down the road? If so, then it might be possible to justify a capital investment in an air compressor. That doesn't mean that you should purchase a compressor, not at all. However, with a compressor it is possible to leverage the whole situation by building a NITROX stik and running premixed NITROX through the compressor. At this point, inspections of various kinds can be done by you. The obligation to display an "oxygen clean" sticker and various other labels becomes optional. In effect, you and your friends can become a cooperative, sharing costs and various duties.

 

[jonahfab]

Look inward. Just what is your committment to diving? How old are you? What is your financial situation? Can you see yourself still diving 20 years down the road?

Thanks for all the info guys, definitely have a good start at things I need to look at with this. I am extremely committed to diving, just ask my wife.
Unless something extreme happens I see myself diving for a long time.
I do have a pretty good relationship with my LDS and am working on my DM through them. The nice thing would be that their DM's get free air fills, so that was one aspect in deciding final costs. I definitely have some reading and research ahead of me.

 

[LULA]

Hi.
I'm finishing my gas blender course and one of the equipments that my instructor told us, to make the top offs in local centers was a portable filter with a yoke converter, that allows to use compressor that is not ready for O2 compatible air.That is we make the partial O2 filling at home and top off at a center.Since I don't know what brand those filters are could someone tell me something about it.:huh: :huh:

Thank you.

 

[Mike Newman]

I understand and respect your desire to DIY it on your oxygen blends. But have you done a 'business appraisal' on the idea. What I mean is, will it really be more economical for you to invest in the Oxygen bank and equipment rather than get your fills from a reliable LDS? Or are you concerned to get mixes that are not easily available locally?