Independent Doubles vs. Isolated Doubles

[Thalassamania]

Ever seen tanks with either H or Y valves doubled up in this manner?

Yes, but usually not "twins" in the sense that one tank had travel mix (#1 pony tank had backup bottom mix) and the other "independent" had bottom mix (with slingshot), a second pony had pure oxygen.

 

[plclark196]

Not sure i understand? You mean independents each with a H or Y valve so 4 x first stages ?!

Ive done it with Y valve tanks once abroad - simply used 1 first stage per tank and kept the other valve on each tank closed. Yes its messy but it worked.
Ive only been to one place that HAD H/Y valve tanks anyway.

Yes, ...H valves , one 1st stage per post and shutting off one side per tank....and isolated doubles- Voila!. It does sound a bit ...ah, awkward ... and yet I happen to have two LP85's with H valves that I like to use when doubles are , for whatever reason , not wanted. There have been times when traveling with only these tanks that I wish I could back mount double them....and in a sense have a LP85 pony bottle.

 

[String]

Yes, ...H valves , one 1st stage per post and shutting off one side per tank....and isolated doubles- Voila!.

I know what H and Y valves are but cant see the relevance earlier to twinning up when abroad unless you routinely take your take valves with you.

They're ok but you have to be really swift with your shutdowns due to the small size tank. Better than nothing though.

 

[plclark196]

When I say travel with I refer to driving trips where the tanks and gear are in the truck. I don't like taking valves on and off to accomodate a dive. Aren't tanks supposed to be vis'd after/between changing a valve?

 

[grazie42]

When I say travel with I refer to driving trips where the tanks and gear are in the truck

I think you are pretty unique in your definition of "travel"...do you ever not "travel" to dive?

 

[plclark196]

well, to me travelling to "wherever" by plane is going to mean different gear than travelling by car or truck etc . This difference is always at least tanks ..

 

[DA Aquamaster]

Unlike manifolded doubles or independent doubles (with normal valves), a set of independent H valved tanks makes no sense.

Independent H valve tanks create a wonderful opportunity to open one of the the reg-less posts while trying to shut down a freeeflow and in effect creating your own additional gas failure. And in addition to worrying about a roll off, you also woudl have to worry about gas loss due to a roll on of one of the unused posts.

 

[Thalassamania]

Unlike manifolded doubles or independent doubles (with normal valves), a set of independent H valved tanks makes no sense.

It does if the two cylinders contain different mixes.

 

[DA Aquamaster]

Carrying back gas with different mixes is also a great way to get killed.

You don't have the same ability to see and follow the hose visually or tactilely from tank to reg. The potential for an error in gas switching is IMHO way too great.

 

[peterbj7]

Why not route hoses from the right post to the right of the body, those to the left on the left? And use distinctive second stages.