Doubles - How to learn?

[lamont]

Can you reach your valves? If so, you're good. If not make the necessary changes so you can. There's nothing special about doubles, you dive them as you would a single tank. If anything, doubles are easier. What is it you think you need to learn?

If you actually have a gas loss issue coming from the manifold / first stages you do need to learn the process of how to deal with it. A lot of people don't understand how an isolation manifold works at first and need it explained to them as well, and there's always the hose routings and logic behind which hoses come off which posts...

 

[lamont]

What are some opinions on independent twin setups? I have just started diving a set, found them pretty easy to manage over the manifold option.

Fully independent tanks are going to produce issues more frequently that lose you access to 1/2 of your gas, and will complicated gas management, but you do not run the risk of complete gas loss through the isolator.

The nice thing about a manifold is that in the common failure case where you've lost a first stage, you just isolate it and switch to the other first stage and still have access to all your gas. For solo divers where any chance of catastrophic failiure of the manifold is unacceptable then independents may look more attractive since gas loss is always restricted to 1/2 gas for any one failure.

 

[grazie42]

If you´re only going to dive the doubles recreationally, I´d side with the "go dive"-crowd. If you have a failiure you´re no worse of than in singles (likely better off). Just make sure all valves are open before you get in...

Go dive, get comfortable and enjoy...I´d say that the biggest danger is staying past NDL´s...

 

[Divin'Papaw]

If you´re only going to dive the doubles recreationally, I´d side with the "go dive"-crowd. If you have a failiure you´re no worse of than in singles (likely better off). Just make sure all valves are open before you get in...

Go dive, get comfortable and enjoy...I´d say that the biggest danger is staying past NDL´s...

Several folks have made an interesting point that I hadn't really considered. That is that one option is to purchase your set of doubles and have them setup by your LDS and then simply learn to dive them and treat them as one large tank. Leave all of your valves open and dive recreationally as you would a single. Then, once you've gotten down the basics of buoyancy, trim and managing the weight out of the water, begin to learn how the manifold works and the valve drills to isolate any failure either from experienced mentors or a workshop/class like the one Duane mentioned. Good stuff to think about.

Based upon some posts I've read here recently, especially those by GDI, it seems to me that for those planning on moving into Technical diving it would be a good idea to acquire your doubles and learn to dive them well BEFORE moving onto your Tech classes.

 

[rjack321]

All good points (about diving them as one big tank which just has a few extra failure points) on the path to learning.

Just be absolutely sure that the isolator is open when they are filled. You'd be surprised how many shops either close it or put 2 fill whips on, or all sorts of other crazy ideas.

 

[Rich Courtney]

There seems to be a growing interest in moving to doubles prior to moving into formal technical training. For someone who is a recreationally trained diver who wants to move into and become comfortable diving doubles prior to any tech training, what is the best approach to do this safely? There is a body of knowledge and skills involved that is not taught in OW/AOW classes.Thoughts?

If it helps, I've started doing a workshop to cover just that! It's primarily designed for recreational divers who've completed Cavern/Intro using a single tank and have decided to continue on with their cave training or those divers who are looking for gas certifications beyond Nitrox. I can't teach a student how to dive in tech gear during a class, so I figured this would give them a head start....

Most importantly, it also gives them a chance to try out technical gear and decide if they want to make that kind of investment, because it isn't cheap

Here's a link to the page on my website....

http://caveandtechnicaltraining.com/TechnicalDivingWorkshop.htm

Hope this helps and good luck with everything

Safe diving,

Rich

 

[scubafool]

Great idea for a class, Rich. I hope that this is a successful venture for you, as I think that many people could benefit from it.

Based upon some posts I've read here recently, especially those by GDI, it seems to me that for those planning on moving into Technical diving it would be a good idea to acquire your doubles and learn to dive them well BEFORE moving onto your Tech classes.

I had SO much coming at me in my Intro Cave class, that I am truly glad that I wasn't trying to learn to dive doubles at the same time.

 

[Debraw]

I just did three dives in my first set of doubles last weekend. I wanted to make sure I could handle the weight of the tanks, complete a weight check and then work on my bouyancy. When I thought I was level, I wasn't. When I was level I felt like I was tipping forward. I moved the wing down and that helped a bit. I think two or three more dives and I will be able to get a handle on it. Rent a set, buy a set, go out with some shop people, or a buddy who currently dives doubles and sit on a platform until you feel good. Then try just diving around. It does take practice. Good luck and happy doubling!

 

[Sawllkwa]

I just did three dives in my first set of doubles last weekend. I wanted to make sure I could handle the weight of the tanks, complete a weight check and then work on my bouyancy. When I thought I was level, I wasn't. When I was level I felt like I was tipping forward. I moved the wing down and that helped a bit. I think two or three more dives and I will be able to get a handle on it. Rent a set, buy a set, go out with some shop people, or a buddy who currently dives doubles and sit on a platform until you feel good. Then try just diving around. It does take practice. Good luck and happy doubling!

Actually just finished a couple dives with one doubles (for the first time). The first dive I was silting and bouncing off the bottom like an OW student, but had it pretty much under control the whole second dive. I actually dove a year with a wing, P-weight and backplate before the doubles, and the transition doesn't seem as hard.

 

[texdiveguy]

Diving doubles is just like anything else you try for the first time,,,,just a small and short learning crve---Practice-Practice!