Filter Canister for Hyper Air

[ssscuba]

I have searched this board but no luck on Hyper Filtering my air. Anyone have a cheeper way to do it? I have found the normal canisters for about $500 and filters for $80 or so. Anyone have any other options? or somewhere to locate a canister used?

[dmdalton]

O2 Hacker's Companion from Airspeed Press has plans in the 4th edition of the book.

Good luck.

Dave D

[pescador775]

I assume you want something on the cheap. Nothing wrong with that but one could ask about the context of what you are doing. What is the air source and present filtration? What are you filtering this air for? If you already have a compressor with modern condensator and filter I suggest you buy two things: a mil surplus, 50 dollar, inline filter canister from Airtimeair and a 25 dollar 5 micron inline particle filter from Compressed air specialties. People are getting too hyper about their air, IMO. Five hundred bucks is ridiculous to some and reasonable to others. I'm in the former set.

[oxyhacker]

There are some pictures at
http://www.airspeedpress.com/gallery.html

and several of the surplus compressor people who sell on ebay are selling surplus filter housings which have been adapted to take breathing air filtration cartridges at fairly reasonable prices, though I haven't examined any of these myself.

Pescador, I'm not sure what you are suggesting in your post. Are you saying to add just a micron filter inside the surplus housing, or a surplus housing with the usual breathing air media inside, and a micron filter as well?




dmdalton once bubbled...
O2 Hacker's Companion from Airspeed Press has plans in the 4th edition of the book.

Good luck.

Dave D

[canuckdiver]

would a HEPA filter element such as the ones from mcmaster-carr in a surplus housing do the trick?
I live in an area where the high-pressure type filter cartridges are tough to get.

[ssscuba]

I went and ordered the book, as it looks like well worth the $35.

My air is grade E now, just trying to make it oxygen ready for mixing.
Thanks for all the suggestions!

Does anyone know where these "hydraulic accumulator" come from, are they a car part or plane part?

[pescador775]

Okay, hacker, I guess I owe an explanation. I realize that the Lawrence factor cartridge contains a fine ceramic disk inside the plastic case. That's good, IMO. However, some folks might be tempted to take apart an old canister and repack. Sometimes, the ceramic disk is non reusable.It might be replaced by a polyester filter pad which is not as fine grained as the disk. The main danger in putting air into a tank already charged with oxygen is oil and carbon particles. Oil is taken care of by the multisorb, charcoal and 13X. What takes out the particles? Some of us think that ordinary 40 micron pads are sufficient. For those who don't, like the Navy, there is a SS inline filter available which will filter down to 5 micron. It is screwed into the fill hose and has a replacable element. Only thing is, it costs 60 bucks, not the 20 that I said earlier, oops. Anyway, I added that little gimmick as a defensive measure or for the overly cautious who are also on a budget.

Pesky

[Stone]

Ssscuba,

There is another thread Here (http://www.scubaboard.com/showthread.php?s=&threadid=17652) that indicates continuous blending is an alternative to having to hyperfilter your air for partial pressure blending. Oxyhacker's book has plans for the premixer. This is the path I am currently on.

[norcaldiver]

oxyhacker once bubbled...
There are some pictures at
http://www.airspeedpress.com/gallery.html


Oh yeah! I'd much rather have that thing sucking up space in my garage than drop by the shop and get my $2 fill.

[Stone]

You're a lucky guy. My 32% fills cost $8 (10$ if I don't buy a 10/20 fill-card up front).

[oxyhacker]

The nearest shop to me that does nitrox is an hour away, and you have to leave your tanks for a couple days.







norcaldiver once bubbled...


Oh yeah! I'd much rather have that thing sucking up space in my garage than drop by the shop and get my $2 fill.

[Genesis]

and like him, I have some issues with the choices around here.

"One offs" are all $10 for 32%, and some of the shops charge extra for 100s or 120s.

All but one shop will not reliably fill while I wait. The one that WILL reliably do so has a guy there who is personable and good - but he doesn't work 7 days a week, is about a half-hour away, and is two trips over a toll bridge (one each direction) to get to and back.

I've put over 50 dives in my log in the last four and a half months. While the winter may keep me out of the water simply due to it being too darn cold, that's only a couple or three months. At that rate, with my dive buddy, we will be logging somewhere in the neighborhood of 200 dives a year.

At $10 a tank that's $4,000 worth of Nitrox annually!

That compressor is sounding rather good - fill whenever you want, mix your own nitrox at "optimum" FO2s.....

[dmdalton]

norcaldiver once bubbled...


Oh yeah! I'd much rather have that thing sucking up space in my garage than drop by the shop and get my $2 fill.

Glad you scored such a good deal on air (I assume that is all you get for your $2).

Since I rarely dive air, and rarely dive nitrox, I've paid quickly for my compressor (used) and gas setup. Trimix fills are costly going from about $50 a fill on up to over $100, for doubles, depending on size of tanks and HE content. I've heard of one shop in my area that charged $80 for a single AL 80! You think getting nitrox on demand is hard, try getting a trimix fill!

Hats off to Vance Harlow (oxyhacker) for the info he puts out in his book, Oxygen Hacker's Companion. Best $35 I've spend on dive info. I couldn't of bought the info elsewhere for $1000 (I tried!).

Dave D

[padiscubapro]

dmdalton once bubbled...


Glad you scored such a good deal on air (I assume that is all you get for your $2).

Since I rarely dive air, and rarely dive nitrox, I've paid quickly for my compressor (used) and gas setup. Trimix fills are costly going from about $50 a fill on up to over $100, for doubles, depending on size of tanks and HE content. I've heard of one shop in my area that charged $80 for a single AL 80! You think getting nitrox on demand is hard, try getting a trimix fill!

Hats off to Vance Harlow (oxyhacker) for the info he puts out in his book, Oxygen Hacker's Companion. Best $35 I've spend on dive info. I couldn't of bought the info elsewhere for $1000 (I tried!).

Dave D

Let me add my 2cents...

If your ultimate goal is high grade hydrocarben free gas, youll want to add a back pressure regulator.. 1st off water vapor degrades the filtermedia quickly and some chemicals (ex hypoclite stops working above a dewpoint of -20f).. The only way to really keep dry gas is to keep approx 2000-2500psi back pressure on the filter stack..

[pescador775]

This is also called a pressure maintaining valve and I concur with padi. SSScuba, you certainly need one of these. If you have a name brand unit there is probably one installed. Problem is, there is little consistency in valve pressure settings. I have checked Bauer BP valves which were set at 500 psi, too low. The Navy's portable compressors will sometimes be set at 2400 psi. Those that are used in aircraft are usually set at 1800 psi. Those used by the Army may have no valve at all. Depends on when they were made because the need for the BP valve was not generally recognized until the early 70's. There is no question that there are tradeoffs for adjusting these valves, heat and wear being the big one. However, the higher the setting, the better quality of air. For purposes of producing dry, oil free air, the higher setting of 2400 psi is best. For general purpose use, portable compressors should, IMO, have valves set in the range 1200-1800 psi. My Bauer (dive locker) compressor is set at 2400, portable at 1200.

Pesky

[oxyhacker]

aka constant pressure valves, constant backpressure valves and priority valves.

At the risk of being repetitious, many older compressors don't have them, and I think MaxAir still has to add them to the Coltris they bring into this country because they don't normally come with them.
They are available quite reasonably as add-ons from Aqua Enviroment and can be added to any compressor. A lot of filter systems, like those from Lawrence Factor, include a priority valve.

If you find yourself using a compressor not fitted with one, you can get the same effect as long as a whip valve is fitted by simply shutting the whip valve down so that the pressure builds to the desired 1600-2000 psi or so in the filter stacks, then opening it incrementally until the pressure stabilizes there. It's not just the coalescor/separator/drier that works better at higher pressures, most of the media is the stack do.


pescador775 once bubbled...
This is also called a pressure maintaining valve and I concur with padi. SSScuba, you certainly need one of these.

[pescador775]

I checked, they have BP valves. It's 'Aqua Air Industries':

http://www.aquaairind.com/Index/Regulators/AEReg.htm

Personally, I like the mil surplus Stewart Warner BP valve. Precision adjustable from 1200-2400 psi, if you can find them. The Aquas look good, too. That's the neatest manifold arrangement. I use a similar design on one of my compressors. The filling armature, which is a piece of brass hex stock, is drilled and fitted with BP valve and overpressure valve. Not as neat but works well.

Pesky

[oxyhacker]

AquaInd appears to be just a reseller of the Aqua Envirionment line I mentioned, as are many compressor suppliers. I usually go direct to AE when I need thier products because it's cheaper if one has a letterhead/dive related biz name and can get the discount.



pescador775 once bubbled...
I checked, they have BP valves. It's 'Aqua Air Industries':

http://www.aquaairind.com/Index/Regulators/AEReg.htm

Pesky

[ssscuba]

Well back to my post that started this thread. i am considering just upgrading my current filter to a hyper pure one for now to save on initial investment. they look to be about $40 more per filter. I figure thats only $80-$160 more per year to hyper filter all my air.

The next question, is i have 4 banks i need to go from the E grade to hyper. do i just run them down and install new filter then bleed for a while and go for it. or will the .05% of old E grade air contaminate my entire idea?

Thanks for all the good info before!

[pescador775]

I presume that you mean that you have a four bottle bank and not four banks. Yes, just dump the air and refill. Watch for condensate on the pigtail manifold so that you don't drive any moisture back into the bank. That's only if you have to reconnect the compressor whip. Otherwise, not.

The bank acts as a trap for any compressor generated moisture or oil so 'contamination' is not likely to affect any scuba tank that you are PP filling and mixing. Moreover, it's not likely that there is any significant contamination anyway, grade E notwithstanding.