New Doubles

[Tom Winters]

I'm quite disturbed that virtually no one in this thread mentioned that diving steel doubles with a wetsuit is a very bad idea.
That being said, once you get into drysuit diving, I would suggest AL80s or PST 100s for doubles.

A person who could not swim up -10 pounds from depth has no business diving with such deficient locomotive skills. There are a lot of posts about diving doubles with a wetsuit where people opine about the inherent dangers of doing this. I only dive wet with doubled LP85s or superpumped LP120's, both with deco bottles.
Most dives, I never add anything to my wing and I'm neutrally buoyant at the finex of the dive. I control my position in the water column simply by breathing.
I had a set of aluminum 80's that were twinned but they're history now. Steel all the way baby.
The biggest problem with doubles is people injuring their backs climbing out of the water of handling them at the fill station. Easy enough to mess up your back, and they take forever to properly heal. I see way too much of that, so be careful.

 

[matt_unique]

I think double 120's would be too heavy to be convenient. A fully charged 120 weighs 56 lbs as I recall. Doubled with bands, etc. and you would be lifting a lot of weight.

If money were no object I would get double HP steel 100's. I had 80 alums so I doubled those when I moved into doubles. I can do two deco dives with approx 20 min bottom time on each with my double 80's. For example, dive 1 to 150' for 20 min, dive 2 to 120' for 20 min. If my deco gas system failed on dive 2 I would still have enough gas to complete deco on dive 2. I think 120's would be overkill and too heavy.

--Matt

 

[Nic160]

I'm diving faber 108's, as Tom said they are very heavy when you're not in the water. Once I'm in the water I love them. A suggestion from me is purchase something that you can handle in the water and out. Start with a smaller set then move up if you have no problems. First time you take a fall with Dbl 130's(any heavy tanks) you might wish you had gotten something smaller. I've seen it before ! I'm cosidering doubling up a set of steel 80's just because they're easier to tote to and from the caves. Or when I don't need the extra air.

 

[jgarysmith]

Tom,

Good point. I sure hope I could swim up HP 100's if I had too. I never had to, so I am not sure how hard it would be. I just preffer to dive in a wetsuit in warm water. I am 5'11 and weigh 195. I am not a body builder by any means, but I am in decent shape. I am not over weight or anything.
You always hear about having to use a dry suit when diving doubles, but I have seen more people in wet suits in North Carolina with doubles than dry suits.

 

[Mark Vlahos]

Tom,

Good point. I sure hope I could swim up HP 100's if I had too. I never had to, so I am not sure how hard it would be. I just preffer to dive in a wetsuit in warm water. I am 5'11 and weigh 195. I am not a body builder by any means, but I am in decent shape. I am not over weight or anything.
You always hear about having to use a dry suit when diving doubles, but I have seen more people in wet suits in North Carolina with doubles than dry suits.

jgarysmith,

I dive double steel cylinders in both fresh and salt water in a wetsuit without any problems. My solution to the redundant lift problem is to use a double bladder wing. When I took my deco procedures class I swam double LP 95's up from 20 feet to the surface in fresh water. I started on a platform, drained all the air out of the wing and headed up without a push off from the platform. It was REALLY hard, but I made it.

Lots of people don't like the idea of wetsuits and double steel cylinders. A dry suit introduces a moderate amount of redundant lift and has one low pressure hose with one inflator mechanism. A redundand bladder wing or an additional single bladder wing when properly sized introduces adequate redundant lift and has one low pressure hose with one inflator mechanism. True, if the drysuit inflator leaks air into your dry suit you will probably feel the air or notice it more quickly. A redundant bladder with a leaking inflator is more difficult to identify, but easier to manage once discovered.

The choice is yours about what to do, but I would not dive double steel cylinders without some sort of redundant lift. A mistake in this area in the open water column could be the last mistake you make.

Good luck with your doubles,

Mark Vlahos

 

[jgarysmith]

Mark,
Are you the Mark that dove with Dr Steve here in Va Beach? I have dove with Steve before and know him frio the board.

 

[Mark Vlahos]

Mark,
Are you the Mark that dove with Dr Steve here in Va Beach? I have dove with Steve before and know him frio the board.

Yep, that would be me. I hope he said good things about me.

Mark Vlahos

 

[limeyx]

The HP120's are tall tanks (28"), but skinny like an AL80. They do weigh a fair bit but not that bad.

I have LP98's and I find them too short when wiggling into them, but I guess everybody is different in that sense.

If you already have 2 120's might as well band them up and take them for a dive, then you will really know how they feel above and below water.

The HP100 are a nice size and if they will provide you with enough air for the depth you are doing then go for it.

It comes down to your size and the size of the tanks. Other thing you have to keep in mind is the type and depth of diving, those 85's might not be enough for a deep dive.

The problem with the HP100 is that (in my case anyway) I tend to surface with *just* not enough gas to do a second dive on them, which is really annoying.

My buddy uses twin HP 119's and can do 2 dives on them, but they are a lot to lug around.

 

[limeyx]

Derrick,I agree on the Dry suit comment, but I just find it hard to dive in 80 deg water in a dry suit. Most of my diving will be off Hatteras and Morhead. And, your slinging suggestion is a great idea.

Joel, thanks for the suggestions. I am leaning towards the 3442 100's.I will probably buy from you since you have a great reputation. We are not seeing much Worthingtons in our area so I am not as familiar with them as PST's. Nobody can PST around here.

Thanks for the replies

But you'll find it even harder to dive in *any* kind of water if your wing has a failure at depth and because you are using a wetsuit you crater into the bottom...

 

[matt_unique]

... but I would not dive double steel cylinders without some sort of redundant lift. A mistake in this area in the open water column could be the last mistake you make....

Ditto - I would never dive doubles without redundant lift.

--Matt