H2Odyssey Extra Air Source

[Slow]

Another nice thing about the 6 cft is you can fill off your first tank. Some of the charters I prefer do not have compressors on board, so filling a 19 or bigger won't be as convenient.

Interesting point...I hadn't thought of that advantage. I did like the ability to fill from first tank, but hadn't really thought about the fact that a 19cft filling off the first won't work so well...thanks.

 

[Basking Ridge Diver]

[[Edit: both Basking Ridge and I are wrong in this post...see later post]]

Actually BaskingRidgeDiver is not wrong - otherwise you could ascend at 240 feet per min and not need a pony...

It all comes down to view point - why ascend at 30, 60, 120, or 240 feet - safety?
Once you answer that question you can start to derive your own formulas that work for you...
YMMV

 

[Slow]

Actually BaskingRidgeDiver is not wrong - otherwise you could ascend at 240 feet per min and not need a pony...

It all comes down to view point - why ascend at 30, 60, 120, or 240 feet - safety?
Once you answer that question you can start to derive your own formulas that work for you...
YMMV

Well, I picked 60 feet/min for this calc because I was trying to find the MINIMUM reasonable amount of gas. 60 feet/min is the max reasonable ascent rate given in the training materials I learned from. Would rising that fast from 120 feet have significant risk? Yes. I am definitely not recommending anything to anyone...although I doubt anyone would recommend going faster than 60 unless the alternative is drowning.

FWIW, I'll remove the offending comment from my post...I now understand what your point was...

 

[Kharon]

This is the type of 'real diver' comments I was referring to. Not helpful or informative in the least.

Actually, I disagree. The post points out first, that every "fact" stated as dogma by SB "experts" shouldn't necessarily be taken as gospel from the scuba gods. This is the internet, and I understand that they can'e put anything on the internet that isn't true. Nonetheless ...

Second, it points out that every type diver's needs are (at least somewhat) different. And even within a type there may be, probably are, variations in needs. A rec diver staying above 60 feet, diving tropical locations, with no current, in high vis water doesn't need anywhere near the equipment that a tec diver making deep penetrating dives in cold water with low vis does. The problem is that the SB "real divers" tend to believe that the way they do things is best for everyone in every circumstance. That's just not so.

Third, it points out that number of dives or courses is a poor metric by which to judge the quality of the advice being given. You need to evaluate and do some thinking for yourself.

Fianlly, it points out that someone who is experieincing emergencies may not be the best person to get advice from.

 

[Chip Elliott]

I just bought this in the 19cf. Just got it yesterday and it is a well made little setup. One advantage is that the 1st and 2nd can go on any size tank in the future, as long as it is a DIN setup.

 

[AdivingBel]

Funny how the thread went to the size of the tank without mentioning the unplanned "OOA test" with an insta-buddy. If you were MY insta-buddy and you signaled a fake OOA without talking to me first before we splashed, I might just whip out my BFK and make it a REAL test. Just sayin' Carry on...

 

[2airishuman]

I even tested a buddy once and it took him a while to get me his alternate reg. He later said to me, "I didn't think we were testing that today" and "I knew you weren't OOA." While he was of course right on both points, it left me feeling a bit...um...less than enthused.

I don't do skills work with a buddy unless I've arranged it before the dive. In general I also try to tell anyone else who may be present, too, if I'm going something that could be misinterpreted as an emergency.

So, I've decided I want to carry a small pony/bail-out with minimum size of 6 cft. Using the rather conservative ascent times calculated on the DiveNerd site, that would get me to the surface from 60 ft. w/ a 0.6 RMV. Of course, if deeper, one might need to be a bit more aggressive in surfacing, but it seems pretty much in the realm of you-probably-won't-kill-yourself.

Pony cylinders are a source of great controversy and discussion on SB. There is no broadly accepted standard on sizing, regulator setup, or how they should be carried for a recreational dive. I plan for a 30 fpm ascent because that is how I train and that is what my computer is set for. I typically plan a 1.0 RMV, a 30 second problem solving interval at depth, and a 1 minute surface reserve. In uncertain surface conditions I may include a larger surface reserve. I have 11, 19, and 40 cf pony bottles, and I choose among them based on the nature of the dive.

I would suggest practicing ascents and figuring out how you'll use your hands. I don't think you'll want to hold the whole assembly by nothing but the mouthpiece, so it will take one hand. You will need one hand to dump air from your BC. How will you see your computer (or depth gauge)?

Anyway, for someone new, I like having this option. The price was under $300 all told and I think it beats things like SpareAir for around the same price. I haven't seen many reviews of the Extra Air Source here (or anywhere really...my LDS was intrigued to check it over since they'd never seen one in the flesh) so I figured I drop my experience here in case anyone is interested in this option.

I believe that the 1st stage/cylinder valve combination for the Extra Air Source is manufactured by Well Marine Diver and is a balanced diaphragm design. Very similar devices are sold by Piranha under a house brand. I'm not sure what they use for a 2nd stage. Well Marine Diver is the manufacturer of most brands of regulators sold in the U.S. I believe that they made your Deep Six regs also, but I could be wrong.

I believe you can remove the ball swivel and replace it with a 2nd stage hose if you conclude that you'll run out of hands during ascent unless you leave the cylinder attached to something.

A little detail on breathing performance. The three things I've spent much time breathing on are my new to me Deep Six regs, rental/student Scubapro regs (I don't remember the models, but we were told they were "nice" for rental gear) and this H2Odyssey thing.

Compared to those, I was a bit surprised at how well the H2Odyssey breathed. I expected it to be rougher than anything I'd used before...it wasn't. If anything, I think it breathed a bit nicer than the Scubapro stuff (although I didn't back to back with those regs). Back to back with the Deep Six regs...well, it wasn't horrible, and from what I can tell the Deep Six stuff ranks pretty highly on breathing performance. Of course, as you noted, this was all only 12' down...

It should breathe as well as anything else if it's tuned to do so.

Many pony regs have a 2nd stage deliberately detuned so they are less prone to freeflow.

 

[Slow]

I don't do skills work with a buddy unless I've arranged it before the dive. In general I also try to tell anyone else who may be present, too, if I'm going something that could be misinterpreted as an emergency.

Some possible slight mitigating factors: it was in a pool on the same day we had previously tested OOA/air sharing, I had earlier mentioned to my fellow classmate/buddy that it seemed like doing OOA/air sharing once wasn't enough (yes, that's a whole other conversation) and we were literally sitting there at the bottom of a 12 ft. pool watching someone else have their skills checked.

I'm not going to say it was a fully defensible action, but now I really do know how that guy would react to an unanticipated OOA. I don't see any other way to know that.

I would suggest practicing ascents and figuring out how you'll use your hands. I don't think you'll want to hold the whole assembly by nothing but the mouthpiece, so it will take one hand. You will need one hand to dump air from your BC. How will you see your computer (or depth gauge)?

The H2Odyssey bag clips to my BC in such a way that I don't have to hold it to breathe from it. So, everything can still be done as normal.

 

[Kharon]

I believe that the 1st stage/cylinder valve combination for the Extra Air Source is manufactured by Well Marine Diver and is a balanced diaphragm design.

Incorrect. The H2Odyssey EAS 1st stage is an unbalanced piston. I do my own rebuilds so ...

 

[Slow]

Incorrect. The H2Odyssey EAS 1st stage is an unbalanced piston. I do my own rebuilds so ...

I think it depends on which EAS you get. The EAS 2 is unbalanced piston while the EAS 3 is balanced diaphragm.

H2Odyssey | Diving Equipment | Air Systems

Check out the links to the RG2V and RG3V first stages.