Regulator setup for doubles...
- Thread starter NorCalDawg
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daniel f aleman
Contributor
Rand,
A DIR configured rig is fine for cave, and with tweeking, fine for other dive profiles as well. My point to the OP was that just asking how a doubles rig is set-up is but half the info that he needs, and I want to know why he wants to use them.
You seem more level-headed than many divers. And I too started to learn to dive doubles by myself, in 1975. Back then we used independent 72's (j-valve) with one reg on each - but we didn't try to do anything with them except get longer bottom time, and <60' at that.
Cave, deep, wreck, sure, but why use them otherwise? One can get fairly longer bottom time with an AL 80 with nitrox than in an AL80 with air, right?. And if he doesn't have a handle on his buoyancy? Sheesh...
I'd like to see him take a Nitrox course and see how he deals with the increased complexity. And, I recommend that any future doubles-user-wannabe' to do the same, regardless of how experienced he is with an air-filled AL80.
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Sorry that you can't use SIS. There's a good group of techies in Rockwall at Blue Sea Adventures, contact Paul Gilbert, http://www.underwateripod.com/instructors.html. They're really good, and it never hurts to dive with others who have put in the time and have gained the knowledge, as you have.
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Here is a current thread with differing general views on rig configuration: http://www.scubaboard.com/showthread.php?t=180942
A DIR configured rig is fine for cave, and with tweeking, fine for other dive profiles as well. My point to the OP was that just asking how a doubles rig is set-up is but half the info that he needs, and I want to know why he wants to use them.
You seem more level-headed than many divers. And I too started to learn to dive doubles by myself, in 1975. Back then we used independent 72's (j-valve) with one reg on each - but we didn't try to do anything with them except get longer bottom time, and <60' at that.
Cave, deep, wreck, sure, but why use them otherwise? One can get fairly longer bottom time with an AL 80 with nitrox than in an AL80 with air, right?. And if he doesn't have a handle on his buoyancy? Sheesh...
I'd like to see him take a Nitrox course and see how he deals with the increased complexity. And, I recommend that any future doubles-user-wannabe' to do the same, regardless of how experienced he is with an air-filled AL80.
------------------------------------
Sorry that you can't use SIS. There's a good group of techies in Rockwall at Blue Sea Adventures, contact Paul Gilbert, http://www.underwateripod.com/instructors.html. They're really good, and it never hurts to dive with others who have put in the time and have gained the knowledge, as you have.
------------------------------------
Here is a current thread with differing general views on rig configuration: http://www.scubaboard.com/showthread.php?t=180942
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Well Daniel, for the past couple years now, a nitrox dive hasn't been any more complicated than a single tank dive. Hard to get task loaded on that.
And I am also waiting to see a logically thought out doubles configuration from you (a link or text)??
He is posting the inquiry here in the Tech forum and wants to take deco classes. He's unlikely to get good instruction with either vintage equipment or vintage ideas... since the OP is unlikely to find a center post manifold with a J valve to go on his 72s anyway
So whatdoyasay? Got a recommended configuration or not? If all the rest of our suggestions are "one of many alternatives" in your mind, presumably you've got some well reasoned alternatives?
Tell us your preferred >130ft deco diving config? Inquiring minds wanna know.
And I am also waiting to see a logically thought out doubles configuration from you (a link or text)??
He is posting the inquiry here in the Tech forum and wants to take deco classes. He's unlikely to get good instruction with either vintage equipment or vintage ideas... since the OP is unlikely to find a center post manifold with a J valve to go on his 72s anyway
So whatdoyasay? Got a recommended configuration or not? If all the rest of our suggestions are "one of many alternatives" in your mind, presumably you've got some well reasoned alternatives?
Tell us your preferred >130ft deco diving config? Inquiring minds wanna know.
daniel f aleman
Contributor
rjack321:
Depends on the dive profile, jack; what I prefer changes. And, that's the point. Are we in a cave or a wreck? How deep are we going? How much deco? And on ALL >130' dives I'm using Trimix.
(I still dive independent doubles sometimes in open water, and I don't recommend that to anyone else.)
An example, a 130' openwater saltwater dive to a wreck for external survey, no stresses, with 40 minute bottom time, first dive of day; I can choose either Nitrox or TriOx:
twin AL80's on an isolator manifold; primary on 40" hose, secondary necklessed on 24" hose bungied under chin, both coming around the right (donate 40"); BC choice, doesn't matter; SPG comes from the left and is attached to BC inflater hose so I can see it at all times; AL80 deco 50% with normal sized SPG and reg for Nitrox; AL30 oxygen with normal sized SPG and reg for TriOx.
Run times at maximum depth: Nitrox, Triox
130':40min 28% 130':40 30/30
40':45min 50% 40':45min 30/30
30':50min 50% 30':50min 30/30
20':70min 50% 20':60min Oxygen
I return to surface with tons of gas in all bottles.
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Why are you changing things? Between say a OW wreck dive with your 40" primary and a cave? What benefit does the 40" have in OW?
daniel f aleman
Contributor
rjack321:
I agree I don't see a reason to change even when I do an easy OW lake dive I use my doubles configured for wreck penetration. Why not be as familiar with that rig as possible so every move is second nature. When **** hits the fan I dont want to think about where an item is I just want to grab it and know its there. The only cave configured item I dont see as necessary for wreck diving is the inflator on the right post for roll off, but I dont have a good argument for not doing it (even if it did ever happen I would just turn the post on not try and breath off the inflator).
daniel f aleman:
So how does the long hose hurt this situation you can still hold on right? Also my regular OW buddy can control her buoyancy just fine and I would prefer the long hose if we had to use it.
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Your reference to a new divers air sharing thread isn't relevant. Deco dives are serious biz. Those early diving skills should be much much sharper.
Bad bouyancy control is bad bouyancy. Don't tech dive if your bouyancy skills are subpar or with buddies who have bouyancy issues. Using changes in gear to somehow "manage" this underlying issue by being closer together still leaves you bent from your deco dive. Or possibly dead.
If you don't know a suitable standard for bouyancy control, there are plenty of DIRF instructors to help show you good control and help you acheive it. (sorry Daniel, just had to mention that
)
Bad bouyancy control is bad bouyancy. Don't tech dive if your bouyancy skills are subpar or with buddies who have bouyancy issues. Using changes in gear to somehow "manage" this underlying issue by being closer together still leaves you bent from your deco dive. Or possibly dead.
If you don't know a suitable standard for bouyancy control, there are plenty of DIRF instructors to help show you good control and help you acheive it. (sorry Daniel, just had to mention that
)
daniel f aleman
Contributor
I have 10,000+ dives, I can sleep mid-water.
And, the ability to tailor one's skill set to the dive at hand is what I respect. The point is that a 7' hose is only needed for single-file air-share. DIR finds that a 5' hose for open water is fine except for "deep" dives. The extra length is just that, extra. But, there is nothing wrong if you and your buddy want to use the 7' in open water, and any other dive profile, IF both of you are capable of dealing with it in a panic situation.
And, the ability to tailor one's skill set to the dive at hand is what I respect. The point is that a 7' hose is only needed for single-file air-share. DIR finds that a 5' hose for open water is fine except for "deep" dives. The extra length is just that, extra. But, there is nothing wrong if you and your buddy want to use the 7' in open water, and any other dive profile, IF both of you are capable of dealing with it in a panic situation.
