Pony bottles VS stage bottles

[RockPile]

What you are describing is not a stage bottle. A stage bottle is, by definition, used to extend your bottom time/penetration distance/etc.

Being an instructor, I respect your training and education level enough to do a little research and see if I’m off base as is the case from time to time. I would hate to think that I was perpetuating falsehood.

Stage bottle: http://wrolf.net/scuba_slang.html
“A separate gas supply which is detachable from the diver.”
This seems pretty open-ended and makes no mention of a proper or “correct” strategy for use.

This site details proper use and rigging with some theory: http://www.dive-rite.com/TecTalk/stage/index.htm
The author uses “deco” and “stage” bottle interchangeably, with, interesting, no mention of the “more correctly” used “bottom stage.” I think it’s worth noting that I was able to find next to nothing referencing “bottom stage.”

There seems to be a bit of diving dogma at work here: that a pony and stage are mutually exclusive ideas. In reality the only difference between a pony bottle and stage bottle is size (though I suppose there is a guy somewhere calling his slung 63 a pony). What they are used for is entirely up to the diver.

My original point was just that a pony-size tank (small) has a limited range of uses (it couldn’t feasibly be used to extend bottom time) and a stage bottle (larger) solves this problem with more air. A stage bottle can be used for extending bottom time, redundancy, deco, lift bag work, or for just looking like a tough guy. If that’s incorrect or unacceptable, it’s news to me.

Thanks,

JB

 

[Soggy]

Stage bottle: http://wrolf.net/scuba_slang.html
“A separate gas supply which is detachable from the diver.”
This seems pretty open-ended and makes no mention of a proper or “correct” strategy for use.

I see your definition and raise you this one:
http://www.5thd-x.com/xducation/stages.html

Purpose: Stage bottles are intended primarily to extend bottom time by carrying extra volumes of gas. The stage bottle will have the same contents as the back gas for that dive. Deco bottles, on the other hand, are utilized to contain gases that will accelerate decompression. As such, their contents will vary according to the depths that the decompression is carried out. While many use the terms “stage bottle” and “deco bottle” interchangeably, they do in fact have two distinct objectives.

Here's a thread specifically on the topic. I have not read it entirely, so it may support your hypothesis or mine, or both:
http://www.scubaboard.com/showthread.php?t=65910

Ultimately it appears that the term is somewhat confused. In light of that, it would be best to use terms that describe the function of the bottle rather than nondescript terms such as "Stage Bottle". Call them what they are: bottom stage, decompression stage, or bailout bottle. A pony is a bailout bottle and its size is irrelevent to the usage of the term, unless you can point out some glossary that says "a pony bottle is a bailout bottle with less than 40 cft of gas." However, in common usage in the technical diving world, when one uses just the word "stage", it implies a bottom stage of gas used to extend bottom time.

 

[Rick Murchison]

Hmmm... let's split some more hairs and stir the pot a bit more...
A "pony" is a small version of something else, in this case a compressed gas cylinder. (We all know what a pony is w/r/t beer, right?) In diving, a pony usually refers to a cylinder of 40CF capacity or less, and it may be used as a bailout bottle, a redundant gas supply, a deco bottle, a stage, a diluent or oxygen bottle for a CCR, or even for a drysuit inflation bottle. Granted, when most divers think of a "pony" they're thinking of a 13 to 40CF redundant gas/bailout bottle, but realize that "pony" is really just a size thing and not a use thing.
A "stage" implies not size, but purpose - and that purpose is to extend the dive by using what's in the bottle, whether it be big or little. A stage could be a pony! But usually a stage is a larger bottle (I use AL80's exclusively for this role). I don't require that a "stage" have back gas in it; for example, I consider a travel bottle to be a stage. The one thing that is common to all stage bottles, though, is that the gas in the stage is intended for use, not for backup, and as far as my perception of what a stage is all about it doesn't really fit well into the "redundant gas" definition.
As for Dive-Rite's lack of separation, their article is strictly on rigging, and as the rigging's the same for a pony or an 80, there's no need to separate the two in the article.
Rick

 

[RockPile]

Soggy,

Good site.

I guess I never thought of "stage" as nondescript. It's just general because its uses very, like "vehicle." It's the same with "pony bottle." It's a bottle that can be mounted all over the place for use only as a bailout but only because it's too small to do anything else.

A stage is big. Can be used (and used CORRECTLY) for a variety of things.

You have an interesting take and it's apparent our debate has narrowed into a semantic cleavage probably more akin to the different diving traditions we come from rather than too an absolute rule. With that I yield. Good talk.

JB

 

[JimC]

Nothing provides 100% redundancy (your "redundant" second bottle could quietly leak by a tank neck o-ring unnoticed while you're swimming along captivated by other things, or by way of an unnoticed freeflow if you just forgot to turn it off). There are simply "acceptable levels" of redundancy. I accept the level of manifolded doubles, "H" valves, ponies, independent doubles...

Yes, the second bottle could have a problem, but this requires 2 failures for the system to break down where manifolded doubles and h-valved singles only require a single failure. Granted with manifolds and h-valves the these failure modes are rare.

I look at it this way: It is more likely for someone on independent doubles to loose there reserve though more common failures like free flows. But it is less likely for independent doubles to loose there ability to extract a diver from the dive due to a failure.

 

[RockPile]

Gosh darnit, Rick. You've dragged me back in.

I agree with everything you say. Just give me this. If you DON'T use the stage, would it then be redundant?

Now I'm done. I've been drafting the same lease all morning...

Out,
JB

 

[Soggy]

If you DON'T use the stage, would it then be redundant?

No, it wouldn't be a stage, it would be a pony bottle....or bailout bottle. Take your pick

"stage" describes usage...gas intended to be used on the dive, usually to extend bottom time or to be used at some staged point of the dive (specific depths, i.e. travel stage or deco stage)

"stage-slung" implies equipment configuration. So, a stage-slung pony/bailout bottle is what you are describing above: a pony bottle slung *like* a stage.

 

[Soggy]

A "pony" is a small version of something else, in this case a compressed gas cylinder. (We all know what a pony is w/r/t beer, right?) In diving, a pony usually refers to a cylinder of 40CF capacity or less, and it may be used as a bailout bottle, a redundant gas supply, a deco bottle, a stage, a diluent or oxygen bottle for a CCR, or even for a drysuit inflation bottle. Granted, when most divers think of a "pony" they're thinking of a 13 to 40CF redundant gas/bailout bottle, but realize that "pony" is really just a size thing and not a use thing.

Technically, I believe you are right. You could conceivably have a pony bottle decompression stage, but in common usage, a pony bottle means a small bailout bottle and nothing else. I've never heard someone knowledgeable about technical diving referring to a 40 cft decompression bottle or a 6 cft argon bottle as a pony.

 

[Spectre]

A slung bottle is a slung bottle, the terms 'stage bottle', 'deco bottle', 'travel bottle', 'pony bottle' when used to describe a slung bottle does not imply differences in the physical characteristics of the bottle, but rather are used to imply both the gas that's in that bottle as well as the protocols for use of that bottle. Pony bottles and stage bottles tend to carry the same type of gas, and the implied difference is pony bottles contain gas that is -not- used as part of your gas plan, where stage bottles are. Travel bottles and deco bottles generally imply deco gas [although a bottom stage could be used as a travel bottle as well], and the implied difference is also what the bottle is used for [although travel bottles are generally an added use of an existing deco or stage bottle].

There's another post where I mention this a little more, but since it's in the context of a pony bottle vs. a buddy, I'll just link it since this is the solo divers forum:

http://www.scubaboard.com/showpost.php?p=1156704&postcount=93

 

[fire_diver]

one went one my back just as I rolled off a boat. it;s loud, it's no fun, and I couldn't hear anything for quite some time.

Holy crap they're loud! I had to vent a cascade system last week for hydro. When I cracked the 4500psi bottles, I thought I had just done permanent hearing damage to myself. At least I could run away from it. Wouldnt want that strapped to my back, 3 inches from my head.

FD