First Doubles Setup

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vel525

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Hey All,

I have been doing a ton of reading on here and over at thedecostop to read as much as I can to slowly transition to technical diving. Long term goal is wreck penetration diving. I know I will have to find a good instructor and take the all appropriate coursework, however, before I do that I wanted to start diving in doubles to get used to it and am thinking about putting my first set together (unfortunately I don't know anyone I can borrow from). I just wanted to get your feedback and thoughts/opinions on my choices. I already dive a BP/W, have good buoyancy, and am very comfortable in the water. I will be diving wet for now as I can't afford a dry suit and a doubles setup. Oh, and for weighting reference, in saltwater, I dive my AL BP, AL80 rental tank, with a 3/2mm full and 5/3 hooded vest under, and need no additional weights. Oh, and I'm only 5'6 and 130#, so small and dense :D. So, here is what I was thinking:
* 2 Worthington Steel80 HP
* 200-Bar DR manifold (I wanted to do a 200-Bar because I want to hold off on buying new 1st and 2nd stages at this point and use my current SP yoke regs. I have two 1st stages and 2nd stages. As I start taking the courses I will purchase DIN 1st and 2nd stages.)
* DR or Highland bands/bolts
* Oxycheq Vertex Signature Series (I was leaning towards 55# just so when I move to larger tanks and/or have to carry additional gas) I choose Oxycheq because that's what I dive now and love my Mach V.

Am I missing anything? Thanks for your feedback.
 
The HP80s will probably be too short, even for someone 5'6" and 130#. Plus, if you're considering wreck penetration, 160 cf is going to limit alot of your dives. I'd suggest you give serious thought to the HP100s instead. They are still very manageable, shouldn't be too tall or too heavy for you and they give you 40 cf more gas than the 80s.
 
I'm new to doubles as well but I'm about your size 5'7" and 130lb. I'm diving HP100's and now that I'm getting the hang of this I really like the way the tanks feel.
Ber :lilbunny:
 
Boy, if you already need NO additional weight with a single Al80 and an aluminum backplate, diving double steels is going to make you REALLY negative. You might consider double Al80s -- they trim out nicely and are inexpensive, and when you get to technical training, you can always break them up and use them for stages.
 
If you're current weighting and exposure combination is correct, I would STRONGLY recomend reconsidering your move to doubles... especially HP steels. Doubles and a wetsuit are a topic of great debate to begin with and not one we want to reignite here.

Suffice to say that you are contemplating increasing your max negative bouyancy from -5 or -6 lbs to as much as -20 lbs. In a skinny wetsuit, not only will you have no redundant bouyancy, but you will have very little inherent bouyancy beyond 20-30 FSW. You need to be super sure that you can swim that rig to the surface or be REALLY good at using a lift bag as a method of back up bouyancy. The latter of the two does not seem realistic at this stage of your diving but I could be wrong.

In my opinion, there is no merit in moving to doubles to "practice" or "get used to them". There's really not all that much to them and in many ways, they can be easier to dive than singles (some ways not so much...). They certainly offer some advantages in terms of redundancy and even convenience but it's part of a bigger system that, in my opinion, should not be considered in it's parts but as a whole. So, I would say make the move when you have a need and get some other things ironed out, like a dry suit, gas management, bouyancy etc.
 
I put this together a while ago, but it is still current.

In the garage are a set of old 72s, 2 sets of 80s, a set of 100s, 3 sets of 120s and a bunch of 40s, and 80s for stages and a single steel 125 with an H-valve. They all have their uses but I find that the 72s, the single 125 and one 40 are the ones I most use for a standard 2 dives per day at depths between 60 and 130' on open or flattened wrecks up here in the Northeast. I use the 72's first dive and then put everything over onto the 125 with no changes in regs or backplate. I use a large 55# BC wing on the doubles a small 35# wing for the single. The 80's get used for penetration diving in the same range and the 100's and 120's go deeper and/or longer. I use the tanks I need for the dive, but I have also been collecting tanks for almost 30 years now.

For you, and after 29 years of diving, every time I get asked about doubles I ask back "what do you want to do?" Doubles let you do two things that a single can't- stay longer at shallower depths and go deeper. Both of these bring on DECO and/or gas planning problems very quickly. If you are not prepared for DECO and gas plans, then stay with the singles and NDL diving. If you want some extra gas as a precaution or for a clean up gas, small 20/30/40 bottles as a pony or stage work well.

Now what do you do with the extra gas - most divers will use the gas for exploration of some type be it wrecks, caves, reefs, or photos. At this point the diving has become a tool that lets you do that other thing.

For anyone who wants to go further and get into doubles. I always recommend starting with the old standard aluminum 80's. Why?

Less cost - for your first set of doubles picking up 2 80's used can be done for less then $160 (sometimes much less, say $50 each), add a manifold (new $200/used $100) bands (new $65-$100/used $50). Total cost $300-$350. Or a little over what you might pay for a single steel tank. A new set of steel tanks, manifold and bands will run at least $750 and can get up to a grand. Also, as you travel around the world you will most likely only find aluminum 80's. So if you plan to travel, get used to using them. I want you to use as much of your $$ for diving, not dive equipment.

Weight - I think you can figure this part out. Steels on land suck and for boats, it is not getting off that you worry about (gravity will see to that) it is getting back on. A fully rigged set of 120 or 130's will be a bit*h to control on a marginal day and bucking ladder.

Now go diving - a lot.

Is this what you really want to do? Do you want to put the time and money into it? Will you get bored in 2 years? The sad fact of it is that many, if not most, of the people who post on this board will drop out of the sport in 3 years or less.

OK, if you made the jump to deep/long diving and need more gas then the 80's. Break up the set, the 80's are now called stage bottles, and get the steel tanks you need to do that thing you want to do. The manifold can be reused and maybe the bands.

Now you have a large set of steel tanks, two 80 stages, and most likely a 20-40 foot small bottle. You now have the tanks to jump 200-250+ feet or go a long way back into a cave- if you want to.

Many will question the 80's because of trim but we can work you through that problem quickly.

Now go diving, - A lot. Play with your rig, adjust the BC/back plate and compensation weights till you get what works for you There is no substitute for experience.

Finally have fun and go diving - A lot.

Pete Johnson
 
As others said before, start with 80's and if you are serious about wreck diving, get some steels later and use the 80's as stages. 80's are easy, light and a good intro into doubles.
 
Boy, if you already need NO additional weight with a single Al80 and an aluminum backplate, diving double steels is going to make you REALLY negative. You might consider double Al80s -- they trim out nicely and are inexpensive, and when you get to technical training, you can always break them up and use them for stages.

I would share this as my main concern as well. I have 2 sets of Worthington doubles, a pair of 119's (actually 95's that are HP rated) and a pair of 130's (108's HP rated). Both are fairly close to the same size (8" diameter and maybe an inch or so length difference, 1 pound per tank difference empty). When I am using a drysuit with a full tech rig/gear (SS backplate, 40 cuft deco bottle,etc. etc.) I don't need any weight. If you are diving a wetsuit, AL backplate and an AL 80 with no weight you would REALLY be negative! (Personally if I were doing deeper work and was that negative, I would either have a dual bladder wing or be in a drysuit).

Unless you have an inordinately high SAC/RMV, I would start with twin 80's and move from there. By the way I use DiveRite bands and I really think they are well made. I have 2 wings for doubles...one is 50# and the other 60#. Probably would only have one but the 60# was an Xmas gift...and on the rare dives where I am hauling 2 deco tanks instead of one or a 80 stage and a 40 deco, I like having the knowledge of a bit more lift capacity.
 
Thanks for the great responses. I will look into the AL80s.
 
Doubles let you do two things that a single can't- stay longer at shallower depths and go deeper.
A single 130 pumped holds close to the same amount of gas as a set of double Al80's. There is one thing the doubled Al80's provide that the single 130 doesn't and it has nothing to do with staying longer shallow or going deeper - redundancy.
 
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