Yet another doubles question

[aaen]

Let me start off by saying I am unable to find the information that I am looking for on this site, that beign regarding the size of doubles to use. Yes I have read through a few of the posts regarding doubles and waht size, but nobody is in my body type range.

So to start off I am 6.0' tall, and weigh in at 260 lbs, I am constantly in the gym working out, heavily into weights so the lifting of the tanks is not a problem. Anyways my question is this, i am looking to purchase a set of doubles and all the wonderful accessoris that go with them, but I am at a bit of a loss with which tanks to go with. Again i am 6', 260 witha musculare build obviously with a bit of a gut, currently trying to solve that problem. I am also a bit foot heavy in my trim, I am able to stay down with an al80 for quite sometime, say about 45minutes at depths ranging from 110 to 50', this was in the Bahamas, so obvioulsy it won;t be as good a consumption rate when in the colder water of cali.

I would appreciate it if anyone had any suggestions, to which tank would be easiest to trim with, was leaning towards shorter tanks as the weight would be higher up on my back, helping out the trimming problem, a friend suggest getting double HP130 but I figure that is overkill.

Thanks

Aaen

 

[Ben_ca]

What kind of diving do you plan on doing? Shore/boat... Cave.. ocean or fresh.....

Most of the Monterey guys I dive with are using Hp 100'S AND lp 85S and if they need more gas they add a stage bottle... this is for shore and boat diving...

 

[robway034]

There are a lot of things that you have to consider and questions that have to be asked/answered. What are you looking to do with the doubles? Caves, wrecks or deep or…? After you got that out of the way.., what’s your budget? As far as the trim thing goes; I have found that the Back Plate vs. harness is a point of consideration. The truth is that most companies offer such adjustable and configurable systems that I doubt you will have any real troubles with trim, regardless of what configuration you go with. It’s just a matter of “trial and error” to "dial it in". I am 6'5"/230lbs myself? I dive a transpac w' a 40lbs wing & 108 steel tanks. My preference is good mix for my consumption rate and for deep dives. If I were a penetration wreck/cave diver I'd go with largest capacity tanks I could physically handle. Several of my buddies (Many of whom are around 6 foot even) dive BP's/steel tanks. One notable advantage to the BP & Steel tanks is that you can drop the equivalent weight from your weight system/belt, So consider that instead of aluminum tanks.

 

[Igodeep]

I prefer steel tanks over AL any day of the week, I also prefer low pressure over high. If you find a dive shop that caters to tech divers, they won't have a problem over filling a low pressure tank for you. They will cost you quite a bit more to put together, but I think they are worth it.

As for the size of the tank, that depends on you. How much air do you think you will need to put in a set of doubles? Have you calculated your SAC rate yet? What specifically do you plan to do with these doubles, and will you be able to add another set later, or do you need a set that will do everything.

I have a set of LP 95's, a set of AL80's and I'm thinking about putting together some LP85's. The LP 85's are a great set. Light and if you pump them up, they hold a lot of air!

 

[scubawally]

let me say this I have never been under water when having too much gas was a problem. Your a big lad, if you want double get the big tanks....then all you have to do is learn to use them. I dive double 112's and have never even come close to running out of gas..... I frequently do 3-4 dives on a single nitrox fill.... however filling these tanks with anything other than air can get very costly.

 

[scott&sara]

I always (diving single or double configurations) prefer fat tanks (8" diam). Personally for wreck and cave diving I use LP95's because it is plenty of gas when they are pumped up to 3,500 psi and there is absolutely no trim shift from full to empty tanks.

If you have a problem filling LP tanks to 3,500 psi then you can get the same tank in an HP version and still have the short, fat tank that gives great balance.

 

[SDAnderson]

Is it an option to learn with someone else's cylinders and then buy your own? Learning to handle doubles takes some time - it isn't easy to master the drunk turtle dance and you'll have the opportunity to find out first-hand what it feels like before you decide on what to buy for yourself.

You should size your cylinders to the task at hand but, for your first set, I suggest going as big as you can manage so that you can keep your options open. If you're a big guy and strong like an ox the 130's are probably about right.

With the ready availability of well-balanced HP cylinders and shop compressors that can fill them, I think LP tanks have lost their competitive edge. I usually recommend HP cylinders, particularly the Worthingtons. If you own your own compressor or have access to a shop that will reliably overfill for you, you might consider the LP tanks but HP is probably the better way to go.

 

[scubawally]

its hard to get a lp130 now...... faber made a lp131 and it is a very big (external volume) tank. I have seen them set up as doubles and they are huge.

 

[Mark Vlahos]

Let me start off by saying I am unable to find the information that I am looking for on this site, that beign regarding the size of doubles to use. Yes I have read through a few of the posts regarding doubles and waht size, but nobody is in my body type range.

So to start off I am 6.0' tall, and weigh in at 260 lbs, I am constantly in the gym working out, heavily into weights so the lifting of the tanks is not a problem. Anyways my question is this, i am looking to purchase a set of doubles and all the wonderful accessoris that go with them, but I am at a bit of a loss with which tanks to go with. Again i am 6', 260 witha musculare build obviously with a bit of a gut, currently trying to solve that problem. I am also a bit foot heavy in my trim, I am able to stay down with an al80 for quite sometime, say about 45minutes at depths ranging from 110 to 50', this was in the Bahamas, so obvioulsy it won;t be as good a consumption rate when in the colder water of cali.

I would appreciate it if anyone had any suggestions, to which tank would be easiest to trim with, was leaning towards shorter tanks as the weight would be higher up on my back, helping out the trimming problem, a friend suggest getting double HP130 but I figure that is overkill.

Thanks

Aaen

I am 6' 0" and 220 lbs. I use PST E8-130's. I would think that these would trim out nicely on you. Of course that is just a guess. Worthington makes a cylinder that is remarkably like my Pressed Steel cylinders, and Faber makes a similar cylinder with the paint instead of the shiny galvanized finish. Faber uses a different process to provide the necessary protection from rust, it really boils down to your personal preference. The cylinders I have mentioned are all 3442 PSI when full and are close in the size and weight characteristics, although there are some differences so you should look closely, don't just take my word for it.

I trim out rather well in my steel backplate in the salt water, and a neutral plastic plate in fresh water. I use a dry suit when the conditions warrant, and a thinner wet suit in warm water. I always make sure that I have TWO sources of lift since the steel cylinders are pretty heavy even in the water.

As others have mentioned, learning to dive doubles will take some time and you will need to spend lots of money to get the cylinders, bands, manifold, regulators, etc... assuming that you choose to dive the doubles with two regs, and a manifold. As far as having too much gas, well that is only a problem a couple of hours after the burrito dinner, so don't worry about that.

Diving doubles is not for everyone, frankly it is a pain in the butt. The increased cost, and special considerations for space on some dive boats might not make it worth the bother. I dive doubles because I spend some time in caves, and a full technical diving rig is entirely appropriate in that environment. I choose to dive my doubles in most if not all other environments to keep my gear configuration the same, that is my choice. Why you do it is your business, but please make your first several doubles dives with a mentor in a controlled environment. I am really happy that my first time I did not just jump off a boat into deep water.

Good luck,

Mark Vlahos

 

[CompuDude]

LP95s are very popular for doubles, as are HP130s and HP100s (and LP85s for smaller divers). For someone your size who can take the larger tanks, I'd say LP95s would be a good bet if you feel the HP130s are overkill. Another option would be HP119s, especially if you're looking for slightly shorter tanks. Stay away from the HP120s, as they're probably a bit too long for trim purposes without being a smidge taller.

I prefer Worthington's galvanized finish to Faber's painted finish, since I dive 100% in salt water. My plan is to double my HP100s, which should cover me for the vast majority of my doubles needs.

Don't overspend on the manifold, check out Salvo, which is well-regarded, nearly identical to the Halcyon and DiveRite manifolds, and considerably less money.

Highland Steel (or XS Scuba, same thing now) is the only way to go for bands. Don't forget that you'll need a different regulator setup (and hoses) as well... you may be able to use your current secondary or you may need a different one, and you'll definitely need an additional first stage.