Dual tanks configuration question

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cathellm

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I am trying to eventually setup dual tanks for diving. I am new into this deal of duals. I've seen it many times, but don't remember how there rig was setup. For duals, I know I'll need a bc, tanks, bands, maifold, 1st and 2nd stages regs. and a back plate.

What I don't know it the tank type that is perfered is? steel or alumin. Then there is din or yoke valves? 200 or 300bar manifolds?

For the regs. I need a primary and secondary, spg, wing hose. How would you hook them up a to 2 first stages, due to the manifold? Anything else?
 
Type of tanks depends on what you are diving with. If you are diving drysuit then you can opt for steel tanks, if you dive wetsuit you should go with aluminum. Valves on most doubles are usually DIN as they are less bulkier.

For regs, you need 2 first and 2 second stages, spg, LP inflator hose and optional second LP inflator hose for drysuit. Right post hose for regulator is usually longer (7ft) and left post is on the bungee.
 
What will you be using the doubles for? If you intend to progress into cave or technical diving, then there may be specific requirements/configurations required by the instructor and/or agency that you use.

Many other aspects will depend on your diving location, particularly in regards to the exposure protection you will use.
 
Usually steel tanks are the norm with a twinset, banded togeather. 85's and 95's seem to be most poular. 2 bolts pertrude from the bands towards your back about 9 inches apart. A wing with grommets down the middle goes over the bols, then the backplate and finally the washers and wingnuts. A manifold with 3 knobs, 1 on each side and 1 in the middle is usually always Din, and 2 1st stages are connected here. With steel tanks, weight isnt usually needed to sink and you can get alot better fills. With the extra air comes more bottom time and possible deco which is why most people take some kind of tech course before making a mistake and getting hurt.
 
Usually steel tanks are the norm with a twinset, banded togeather. 85's and 95's seem to be most poular.

I think your 'norm' is more of a regional skew. Choice of tanks is very specific and generally defined by exposure protection/weighting. Most wetsuit divers, and many drysuit divers, find it impossible to create a safe, balanced rig using steel cylinders.

In my experience, having dived 28 countries on 4 continents, ali tanks are far more popular. That doesn't make them right or wrong... just the preferable choice for those divers in those situations.

With steel tanks, weight isnt usually needed to sink....

The OP needs to investigate the concept of 'Balanced Rig'. The essense of which is that the diver must be able to hold a shallow stop with a nearly empty tank, whilst retaining the ability to swim the rig to the surface in the event of buoyancy failure.

The weighting of the total rig needs to be finely calculated, with particular attention upon the ratio of ditchable and non-ditchable weight.

and you can get alot better fills

I'm not quite sure what you mean by this....
 
I'm not DIR/GUE or whatever, but that is the standard gear configuration for doubles,

It's the DIR/GUE standard. Nothing more, nothing less.

A less strict application of that would be a 'Hogarthian' configuration. A very simular and very popular configuration approach to doubles.... but, again, not the only way to do it.

....let's not lead people into believing that there is only one way to dive doubles. Doing so may limit their understanding and prevent them from fully investigating the myriad of options available.

and is what the majority of all of us use

I don't think that DIR/GUE methodology represents even a small fraction of doubles divers. Most doubles divers use the basic Hogarthian approach, but there is far more adaption and personal preference applied by the majority of divers (which would exclude them from the DIR/GUE model).
 
I'm excluded from that group, hence my disclaimer, but it is rare you see major variations from that setup. The majority of us either still use that configuration or use it with slight adaptations. The regulator configuration is huge, and that is one of the least "adapted" parts of the rig. I don't dive with a one piece harness, I will if that's the other option but you'll never see a backplate of mine with one on there. For new divers though reading through that gear configuration and getting the baseline stuff down there, then they can adapt as they need to.
I don't use a long hose unless I'm in overhead and my can light isn't on my hip. From what I have seen though, the basics of that GUE setup is the basis for all of the doubles rigs. I had mainly posted it for the regulator configuration and the 200din vs 300 din vs yoke. For that stuff, that page is a lot more concise than most anything he'd find on here.

To the OP. If you read all the way through that you'll have a great understanding of the core rig that most of us dive. There are differences in all of our diving. You'll see the DIR/GUE crowd diving primarily Halcyon equipment. This is the brand pushed on that page and there are connections between GUE and Halcyon in the higher ups. It's quality equipment. Overpriced IMHO, but good stuff.

For my doubles rig and why
DiveRite Deluxe Harness QR- I needed the QR because of my build type *huge chest, tiny waist*, and I prefer the chest strap because my arms lose circulation quickly without it.
AL Backplate-I don't need any weight with my steel tanks. With AL80 doubles I wear a SS backplate
300 bar DIN valves-I have older PST HP tanks and didn't have a 200bar option. It would be nice for filling though
PST HP120's for doubles-the tanks I had. They're long enough which I like. I also use PST 100's
HOG regs-used Apeks, but due to lack of parts availability for me *never had a problem with the shops getting them, they just wouldn't sell to me...* I switched.

So as you can see, compared to the Halcyon/DIR setups in the pictures mine are very different. At the same time, they are still based on the same backplate/wing/harness setup. The tanks and regulators look the same. My one exception is if I'm diving in a wetsuit I have my LP inflator hose on the left post instead of the right post. This is mainly to make sure that I know both first stages are functioning properly throughout the dive instead of all of the LP being used from one and only HP on the other. Again though, same basic setup is there with the same fundamentals. I started with the DIR/GUE type setup and varied from there for what I needed. Unfortunately for some, that variation removes them from the DIR/GUE circle. Pros and cons to each, but for me there were more pro's involved in being comfortable while walking around on land than there were of having identical setups to my buddies. Obviously it's move involved with that.

and with that, off to teach a NOAA Scientific Diver class, WOO!
 
Like Mr. Saxplayer I dive HP120's, HOG regs and single bladder wing. I dive a drysuit. I think everyone here has brought up some good points. I would investigate the balanced rig deal. It would likely tell me I could never dive a wetsuit with my gear but in my drysuit and thick undergarments it works for me.
Would love to have some lp tanks really.

are you sure you want to start diving doubles? I ask because I love diving doubles but it definitely adds a few bucks to you rig. My wife almost passed out when I told her I wanted a $1200 "flashlight".
 
https://www.shearwater.com/products/swift/

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