Doubles?

[Blackwood]

Seriously though I didn't have the PADI tables in front of me

google images is your friend

 

[ivobj]

I was wondering about doubles. I'm Just OW. But Al80's just ant cutting It. I dive around 40' to 50' and I'm not a airhog. But I diving For long periods at a time. The max if got at 40' was 58 min cold water 46*. I'm wanting to stay for my max on the RDP. I was thing about Doubles I've been told by my LDS to get a Independent Regulator Set-up, But I was wanting something More like The solid Bar manifolds form US divers Or something.Like the ones with J-values?

I know the dangers of diving so don't tell me not to do It.....

Ok, I answer your questions, manifold with isolator knob is the way to go, don't use isolated doubles, if you have a regulator failure for example, you lost half of your air, while with manifold you still can use all your air. If the failure is in one of the cylinders, you turn the isolator knob and loose half of your air, what would be the same as isolated doubles. The conclusion (at least in my opinion) is that in case of failure, in the worst case you're in the same scenario of isolated doubles, not worse, but in the best scenario you still have all your air supply (what doesn't mean that you shouldn't call the dive!!), so statistics is for manifold with isolator knob.

Now, question answered, I am sorry, but I have to tell you not to go for doubles in whichever configuration without proper training, the complexity is a lot higher, and even diving with singles every weekend, like you said, for years, you are not prepared to dive doubles wothout proper training. There are a series of specific procedures, hose routing and placement, that you must train to deal with. You want to extend your dive? As someone already mentioned, get a single steel 130 or a 120, for shallow dives this already gives you a lot of time, you will also be able to remove some lead as well.

Please don't get me wrong, not my purpose to anoy you with this stuff, but I think is the responsible course of action to advise you the danger of not having proper training.

 

[Blackwood]

The conclusion (at least in my opinion) is that in case of failure, in the worst case you're in the same scenario of isolated doubles, not worse

Worst case, IMO, is a manifold failure.

 

[johnx15]

Thanks crpntr133 But I don't know more then yell because I would be asking I'll defiantly have someone teach me the value drill. I guess my passion to go tech is to yearly but most people around here dive tech even if the ant diving bellow Recreational limits. and this has always inspires me.

 

[JDMerk]

google images is your friend

And sloth is thine enemy.

 

[johnx15]

Thanks everyone.

 

[JDMerk]

Worst case scenario with manifolded doubles...you lose all your gas
Worst case scenario with isolated doubles...you lose half your gas

Either way if you have a major failure as in either case you have already thumbed your dive and should have planed your gas to get you home accordingly, its not like you are going to continue diving with manifolded doubles even if you managed to save almost all your gas.

 

[Rainer]

its not like you are going to continue diving with manifolded doubles even if you managed to save almost all your gas.

Depends on what the failure was. If it's fixable (e.g. unseated first stage), sure, I'd probably continue the dive.

 

[atedeschi]

you do not have to be tec to dive doubles. you say most around you dive doubles get a good mentor, if not you can do the intro to tec course, which u only need 25 looged dives and 15yrs old. it will give you the info you are in search of. i been in doubles since my 2nd yr of diving, its not rocket science. pm me if you want and can give you detials how to setup your config etc.

 

[jtivat]

Halcyon, Dive Rite, Thermo and Salvo are the brands I see most. Personally, I prefer Thermo valves.



But hey, if you want to spend some money to get more bottom time, there are some good deals to be had on closed circuit units.

Isn't it funny how different parts of the country see vastly different gear. I have never seen a Salvo or Halcyon valve in the Great Lakes. I am sure they are around but I mostly see Thermo and then OMS.