Sling a 72

[DaleC]

Why not. Sometimes we overthink these things too much.

My progression was from a single tank with a slung 30 pony (which I would never breath) to a single tank with a slung 80 which I would generally breath half down at the beginning of the dive, the remainder being held as a reserve. This had the added advantage of making the tank only partially bouyant. I wanted to extend my dives but at the same time appreciated the redundancy of a seperate system (something you don't get with just a bigger tank). I found diving a slung Al80 to be no more hassle than a slung Al30.
Eventually I got tired of slinging a big tank and just started diving backmounted twins which is where I still am but I don't regret the earlier experience.
If you dive a neutral Al80 you will have to contend with 5lb's positive bouyancy at the end of the dive (or weight the tank) so either way (Al80 OR St72) you will have to contend with some sort of bouyancy swing (neg - neutral or neutral - positive).

Just remember that carrying more gas can lead to bigger dives and ones capabilities should match the potential one would then possess. That being said, sometimes stepping up ones potential leads to an increase in the desire to learn more about gas management and dive planning.

 

[LeadTurn_SD]

Why not. Sometimes we overthink these things too much....

Mea culpa.

I did actually toy with the idea slinging my old steel 72 (since I rarely use it these days).... but since I had an Al30 and several Al80's I could sling, I never got around to trying it out....

But now I'm moving towards "indy" doubles anyway :scubadive:

Best wishes.

 

[jsado]

Thanks for all the great info. I especially like the idea of breathing it down 1/2 way at the beginning of the dive, then switching to the backmount. The 30 I dive with as a pony basically disappears & I don't even notice it's there. That's what got me thinking about the 72 and maybe extending bottom time. Not necessarily going to try it, just wondering if it was reasonable.

 

[TSandM]

Why would you breathe it down halfway and switch? That's a strategy we use in cave diving, where we are diving thirds. In open water diving, it would be reasonable to breathe the stage down as far as you are comfortable doing, and then switch to backgas, keeping your minimum gas reserve in your backgas tank. Figure the total usable gas, and the appropriate gas management strategy for the dive.

 

[*dave*]

In terms of having a redundant gas supply, it would make sense diving a single. Breathing down a stage when you have redundancy in isolated doubles is one thing, but the slung bottle would be the only source of redudancy diving a single.

 

[Kern]

In terms of having a redundant gas supply, it would make sense diving a single. Breathing down a stage when you have redundancy in isolated doubles is one thing, but the slung bottle would be the only source of redudancy diving a single.

This would be my rational as well.

 

[highlandfarmwv]

Not if you can climb back up the ladder with it!!

 

[rongoodman]

FWIW, the Hymark Al 72s ride very nicely when slung. I used one with my 85s last week on the Lake Ontario wrecks and hardly noticed it was there. I then had a plenty of gas in my doubles for the second dives.

 

[gfyrasng]

If you're trying to extend your bottom time, wouldn't it be easier to just dive a bigger tank? Less equipment and less points of failure.

 

[rongoodman]

If I ever thought that, climbing up the ladder on that rocking boat with just the 85s changed my mind. I managed OK, but I can't imagine doing it with a pair much bigger than that!