double tank equipment
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Everything mentioned should be completely familiar to anyone with a legitimate OW certification. If it is not, the fault belongs to whatever incompetent instructor certified the half-trained diver. A lot of things should be simple to anyone holding an OW certification. An AOW should be able to demonstrate these basics to a new diver.
Weighting properly for doubles is largely a matter of achieving proper buoyancy with tank(s) filled, and anticipating the difference when tank(s) are down to whatever minimum is applicable. Again, this is absolutely basic stuff, and no one should be certified without that skill and knowledge.
There is no real difference in this regard between doubles and a big single. The variety of options available for positioning weights should be no problem for a certified diver to effortlessly learn immediately. The same with configuration changes. If a would-be diver can't do this they should not be certified.
Does anyone still use those huge brick-like consoles? Maybe some innocent sold a package by a dive shop owner.
I've been around diving for a long time. A lot of 'additional training' illustrates the old truism that the one eyed man is king in the land of the blind.
cool_hardware52
Contributor
DaleC
Contributor
I dunno, we all have to start somewhere.
I learned to dive via PADI taking OW and AOW back to back.
I started solo diving around dive 20.
I started diving with a pony at the same time, sometimes slinging an Al 80 as a stage. I learned how to rig and use one off the net for the most part.
From there I backmounted independent twin 72's using what I learned from pony use and the net.
From there I used an isolation manifold, also learned from the net.
Having said that I would qualify my direction by saying I am pretty good at self study and disciplined in application and I have made a few mistakes. Most notably using a video camera, becoming taskloaded and missing a reg swap leading to an OOA on one tank (independent tanks) and shutting down my buddies left post (isolation manifold) pre-dive during my first exposure to them because of confusion over valve directions. You could accelerate the learning curve by taking formal education and perhaps avoid some mistakes but learning on your own, with mentors or off the net isn't impossible or irresponsible. I think PADI offers a good portion of their course over the net don't they. The interwebs are awesome as an interactive resource.
I have never dived with another vintage diver IRL either. 100% of what I do there has been gleaned from books and a great on line community.
I learned to dive via PADI taking OW and AOW back to back.
I started solo diving around dive 20.
I started diving with a pony at the same time, sometimes slinging an Al 80 as a stage. I learned how to rig and use one off the net for the most part.
From there I backmounted independent twin 72's using what I learned from pony use and the net.
From there I used an isolation manifold, also learned from the net.
Having said that I would qualify my direction by saying I am pretty good at self study and disciplined in application and I have made a few mistakes. Most notably using a video camera, becoming taskloaded and missing a reg swap leading to an OOA on one tank (independent tanks) and shutting down my buddies left post (isolation manifold) pre-dive during my first exposure to them because of confusion over valve directions. You could accelerate the learning curve by taking formal education and perhaps avoid some mistakes but learning on your own, with mentors or off the net isn't impossible or irresponsible. I think PADI offers a good portion of their course over the net don't they. The interwebs are awesome as an interactive resource.
I have never dived with another vintage diver IRL either. 100% of what I do there has been gleaned from books and a great on line community.
Completely agree with dalec on that one. (except for shutting down your buddy's valve, that's very mean of you! Bad!)
Same thing as Imla, it's not the first (and certainly not the last) time that I see posts looking very pushy towards training, and those usually don't seem to be "join a community and learn from them" kind of training. Now I agree that English is my 3rd language, but I feel that when many people read the same thing in a post, either the post wasn't clear, or someone is clearly backing off after getting caught red handed.
As for the spg's, while the most typical is 1 for manifolded, 2 for independents, some also dive 2 for manifolded. Their reasoning is: If I have to shutdown the left post for some reason, even if the dive is called, I like to know how much gas I have. I'm perfectly fine with that, I wouldn't do it anymore because I feel it doesn't apply to me anymore, but heck, I've even had 2 spgs on a single tank because I couldn't be bothered removing one, and it's really not that big of a deal on 99% of the dives to have a "major failure point that is an SPG".
For the "extended bottom time and deco", I call major BS on that. That has NOTHING to do with diving twins, it is easy to hit deco on single tanks as well on many "double dive" boats. Many countries do deco on single tanks.
For the setup of the hardware, some dive shops sell and ship the twinsets already assembled. I don't see why one would be required to know how to assemble them, I've never been asked to remove the valve from my single tank for my OW course, why should it be any different with twins?
Sure, it's a good thing to know how the manifold works, but that's very little info and a simple read about them (looking up GUE manifold valves for instance) would give all that is needed for that imo. Same thing for hose routing and procedures.
Taking training makes it go smoother, but not taking training in such cases doesn't kill if the person has half a brain (1/100th of a brain should be enough)
Same thing as Imla, it's not the first (and certainly not the last) time that I see posts looking very pushy towards training, and those usually don't seem to be "join a community and learn from them" kind of training. Now I agree that English is my 3rd language, but I feel that when many people read the same thing in a post, either the post wasn't clear, or someone is clearly backing off after getting caught red handed.
As for the spg's, while the most typical is 1 for manifolded, 2 for independents, some also dive 2 for manifolded. Their reasoning is: If I have to shutdown the left post for some reason, even if the dive is called, I like to know how much gas I have. I'm perfectly fine with that, I wouldn't do it anymore because I feel it doesn't apply to me anymore, but heck, I've even had 2 spgs on a single tank because I couldn't be bothered removing one, and it's really not that big of a deal on 99% of the dives to have a "major failure point that is an SPG".
For the "extended bottom time and deco", I call major BS on that. That has NOTHING to do with diving twins, it is easy to hit deco on single tanks as well on many "double dive" boats. Many countries do deco on single tanks.
For the setup of the hardware, some dive shops sell and ship the twinsets already assembled. I don't see why one would be required to know how to assemble them, I've never been asked to remove the valve from my single tank for my OW course, why should it be any different with twins?
Sure, it's a good thing to know how the manifold works, but that's very little info and a simple read about them (looking up GUE manifold valves for instance) would give all that is needed for that imo. Same thing for hose routing and procedures.
Taking training makes it go smoother, but not taking training in such cases doesn't kill if the person has half a brain (1/100th of a brain should be enough)
I agree. I've described here before my introduction to drysuits: I expressed to a friend (who happens to own my LDS) my desire to one day dive a drysuit. He then loaned me his, we reviewed what *not* to do (I had already been self-studying drysuits), and the very next weekend I went off to a corner of a local quarry to sort things out while he taught an OW course in another corner. This was ca. 1988.
My introduction to doubles was just as spontaneous and unremarkable: I had just returned fresh from my four-day NSS-CDS Cavern and Basic Cave certification courses at Ginnie Springs FL (single Scubapro 75.8? cu ft tank, Y-valve, Scubapro Stab Jacket, Scubapro Mk 10's and Balanced Adjustable and G250 on a 5 ft hose, lantern grip UK 500, Ikelite Mini-C x 2, DR reels). I stopped in at the other local dive shop and purchased a pair of used doubles tank bands made for Al 80's and a plastic backpack. I fitted my PST HP 80's (!!) as independent doubles to my SSJ, and next weekend I went diving with two full cave-certified friends. Per prior agreement, when I reached my training limits, I waved bye as they continued on, and I surfaced. This was in early 1989. I took my initial open water course in 1986 and was certified in 1987.
Anyone who knows me will testify to how cautious and risk averse I am. And how thoroughly I prepare.
While I don't recommend anyone ever doing what I, myself, do, I'm completely comfortable doing the things I do, learning things on my own. And people who know me, experienced divers I sometimes dive with, are comfortable, too, with my choices. In this respect, I'm no different from other divers I know.
None of this stuff is all that difficult at this level. None of this stuff at this level absolutely *requires* formal instruction. Caution and attention to detail and an honest understanding of one's own limitations and experience level are sometimes all that is required. And common sense, too, maybe.
I'm always a bit annoyed (to be honest) when people on here are so quick to insist that someone undergo formal training for this or for that when he/she simply asks a question! On-line scuba communities were not always like this. (Does anyone here remember Jim Cobb's Tri-Mix page?)
Safe Diving,
rx7diver
Adobo
Contributor
If I'm being honest, I am confused as to what your point is. First it seems you are saying that you tried doubles on your own. Then you say you don't recommend anyone doing what you did. Then you are saying that you are annoyed when people suggest a newer diver take some training from someone qualified.
Are you agreeing that getting instruction from someone who knows about doubles is good for a newer diver or are you disagreeing?
Personally, I am just like you - except the complete opposite. I am always annoyed when a poster who clearly doesn't know a topic very well gets told that there isn't much to it and that they should go figure it out (and re-discover the wheel for themselves).
Sorry for the confusion, Adobo. I did ramble a bit, didn't I? Basically, I'm most comfortable simply telling people what I, myself, did/do. I'm not comfortable recommending to people that they should do what I did/do.
So, here's the skinny: (1) I did my first drysuit dive without having taken formal instruction—solo, in a deep quarry! (2) I did my first doubles dive without having taken formal instruction, and surfaced solo! (3) I know other divers who have done similarly. (4) I don't believe that formal instruction is necessary for many of the things that so many people on here are so quick to insist one should get formal instruction for. And (5) I'm not recommending to anyone that he/she should do as I did (or believe what I believe).
Does that help?
Safe Diving,
rx7diver
Adobo
Contributor
[-]I just don't know how else to put this other than to say that every single item in your reply is incorrect. Every. Single. Item. Well, maybe the business about the one eyed man is not incorrect though I have no idea what how it relates to the price of rice in China.[/-]
Edit: I changed my mind. I am out of energy regarding this topic.
Very. Clever. Editing. I think the reality is that you are out of facts, very short on practical information with only moderate experience and bereft of any logical consistency. A formalistic zombie with the zeal of a convert.
Writing that everything is incorrect without any specificity suggests a limited knowledge base and a tiny mind. What's your position on triple and quadruple tank set ups?
Perhaps you know more about reef tanks. I have a couple now, the oldest set up since the 1980s. Lee Chin Eng was one of my early mentors when I was seriously into them. These days simplicity and natural processes prevail.
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