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+--- Thread: Pony bottles (/showthread.php?tid=2397)
Pony bottles - eric myers 2 - 09-26-2005
If you don't use a pony bottle, consider adding it to your gear configuration. Think about it this way, a free flow can happen at anytime, so a redundant airsource is one way to add a little piece of mind and a safety factor!
I dive my 30 cft AL pony almost completely fulltime, especially on "deep dives."
Pony bottles - LKunze - 09-26-2005
Pony's are a viable option. Here's my take on the pony. For dives within recreational depth limits, a pony isn't absolutely necessary if a.) you're diving with a good buddy and b.) you're diving with a high end regulator that's rated for cold water and is properly tuned for cold water conditions. I've never had a free flow with my Apeks even when it once had the I.P. set way too high. Now I keep my I.P. set at about 120 but I once had it set as high as 150 and it still didn't free flow in 36 degree water down to 125 feet so I've accumulated some trust in my regulator's performance. I consider my buddy and our dive plan to be my real back-up for deeper dives. If I don't have a buddy that I trust and have dove with on deeper dives then I don't do the dive period. Now if one were to be diving below recreational limits then a doubles rig would be the best option and a pony or two regs with H-valve would be the second best options in my opinion. Sharing air (two divers huffing of off one 1st stage in a single tank rig) past recreational limits is gonna push even the best regulator into a likely freeflow. Maybe even within recreational limits. I will say though that I have had a chance to dive Matt's 30cf pony rig a couple times. It's setup slung like a deco bottle on the left side and it actually trimmed out and swam pretty nicely.
Re: Pony bottles - LRRP02 - 09-26-2005
Here is my 2 cents. Ponys are okay espicially if you want that little extra assurance when diving high end drift dives. As far as freeze up as long as the air is very low humidity but remember when you inhale the venturi effect drops 17 degrees so in 34 degree water actual is 17 degrees high moisure in your air will give you a freeze up and if it is in your pony guess what when you breathe off it
Re: Pony bottles - eric myers 2 - 09-27-2005
Your Apeks never having had a free flow is pretty impressive! While I agree high performance, cold water rated, and properly tuned regulators (aprox. 120-130 IP) can help lend towards safe diving, having a redundant air source being a totally autonomous system (i.e. 19-30 cft AL or greater with own regulator) can only add to margin of safety.
Additionally, in my opinion the selection of a pony bottle size should fit the diver's dive plan and their physical attributes. For example, if you are a 250lb guy who sucks air like a fat kid in gym class on track and field day, and you plan to dive right to the recreational limits than you should probably use at least a 40cft tank; that is opposed to a 100lb woman who sucks air like a grandma sipping sherry on her anniversary and your favorite depth is 80 feet than maybe you can get away with a 19cft tank. Bottom line your pony, when used as a bailout bottle, should be able to return you to the surface safely from your deepest depth or the first available level depending on the mix.
Regulator Trust: I have heard that before and I have never really been able to understand it. Someone once said to me, "trust your training and your equipment." There was only one problem, that person's equipment was working and mine was questionable. I personally subscribe to the theory that "Murphy's Law is alive and well and living in my gear bin." Someone also once told me that, "Regulators are a mechanical device and mechanical devices fail all the time none of which are all to terribly important except life support devices...better have two just in case!"
H-Valves: H-Valves are a great invention and if I had enough regulators I would probably dive an H-Valve and a pony but I probably would never dive an H-Vavle in place of a pony and here is why. What happens if the free flow occurs at the end of your "deep" dive? You just hit the recreational NDL you have about 750-1000psi left, just enough to return you to the surface right? Wrong, in an instant you blow a o-ring on your H-Valve and automatically lose 500psi before you can reach back and shut down the valve, now what? H-Valve guy is considering a CESA and Pony Guy is sitting at 50ft doing a deep stop and then 20ft for a safety stop!
My little pony:
Redundancy from a fully autonomous system? You just can't beat it unless you add another one (doubles and isolator manifold aside)! Hey, by the way you and I just kind of said the same thing. The best part is I blew off like :30 minutes writing this frickin' post...awesome.
Let's go diving!
[table]Pony's are a viable option. Here's my take on the pony. For dives within recreational depth limits, a pony isn't absolutely necessary if a.) you're diving with a good buddy and b.) you're diving with a high end regulator that's rated for cold water and is properly tuned for cold water conditions. I've never had a free flow with my Apeks even when it once had the I.P. set way too high. Now I keep my I.P. set at about 120 but I once had it set as high as 150 and it still didn't free flow in 36 degree water down to 125 feet so I've accumulated some trust in my regulator's performance. I consider my buddy and our dive plan to be my real back-up for deeper dives. If I don't have a buddy that I trust and have dove with on deeper dives then I don't do the dive period. Now if one were to be diving below recreational limits then a doubles rig would be the best option and a pony or two regs with H-valve would be the second best options in my opinion. Sharing air (two divers huffing of off one 1st stage in a single tank rig) past recreational limits is gonna push even the best regulator into a likely freeflow. Maybe even within recreational limits. I will say though that I have had a chance to dive Matt's 30cf pony rig a couple times. It's setup slung like a deco bottle on the left side and it actually trimmed out and swam pretty nicely.[/table]
Re: Pony bottles - ghosch - 09-27-2005
If you can hold your breath long enough for both your ascent (yes, I know you don't actually "hold" it on the ascent) and your safety stop, then dive w/o a redundant air supply.
Otherwise, nothing beats a truly independant alternate gas supply, IMHO.
Re: Pony bottles - billatlake - 09-28-2005
Well put. Especially considering LRRPO2's comments on moisture. You could find the moisture at depth in your pony, or in your primary!