Pony band - which one and other Q's

[mdsd]

:33:
After reviewing many posts on this board, I am zeroing in on a config for my redundant air source.

Strapping a 13cf to the side of my AL80 with a weight pouch on the other side of the AL80 to balance the load.

Some questions:
1. What is the best band for the 13cf tank? (I would like quick release because I will only use the 13cf for deep dives (>60 ft) or new-buddy dives.)
2. What is the proper orientation for the 13cf tank? Up or down?
3. What is the most cost affordable option for a pressure gauge for the 13cf?
4. What is the most cost affordable option for the first stage?
5. What is the most cost affordable option for the second stage?

 

[MakoSince70]

I have used a 13 ft pony for a couple of years as a back up on deep dives.
My bracket of choice is the QuickDraw. (may not have the spelling) But, you can find them at Scubatoys.com. Has a quick release pin that is easy to use. Cost is around 100.
I prefer the pony in an upright position because my reg seems to configure better that way

I turn the air on prior to the dive. I want the pony in the event of an emergency and do not want to fool with getting it on. Many tech divers will disagree with this statement, but thats my preference.

Low cost reg, spg. Can't help you. I rig a top of the line Scubapro Reg outfitted with a transmitter to a Suunto hoseless spg and computer. A lot of cost for a backup pony but the rig is my wifes primary.

For counter balance wt, I find two pounds added to the bc pouch on the opposite side of the pony works for me.

Check out the QuickDraw, you will like it

 

[Doc Intrepid]

:33:
After reviewing many posts on this board, I am zeroing in on a config for my redundant air source.

Strapping a 13cf to the side of my AL80 with a weight pouch on the other side of the AL80 to balance the load.

Some questions:
1. What is the best band for the 13cf tank? (I would like quick release because I will only use the 13cf for deep dives (>60 ft) or new-buddy dives.)
2. What is the proper orientation for the 13cf tank? Up or down?
3. What is the most cost affordable option for a pressure gauge for the 13cf?
4. What is the most cost affordable option for the first stage?
5. What is the most cost affordable option for the second stage?

Permit me a few brief observations:

1. Pony Tamer is a pretty good option. Here's a photo:
http://shop.divebooty.com/3415.html

2. Regardless of what tank you use, you should be able to turn it off and on. Put a BC and tank on, then reach back behind you both over your shoulder and back behind your waist. Which configuration would allow you to reach the knob of the tank valve?

3. You don't need a pressure gauge on a 13cf tank. Once you go on it you're going up. You'd better know there's enough gas in it to allow you to surface at a leisurely pace. If you don't know that, you'd better sit down and do some math.

4. and 5. When your life depends on a piece of equipment, particularly after some other situation has just added excitement to an otherwise routine dive, it is wise not to go with the lowest bidder. Buy a decent quality regulator and ensure it is serviced regularly.

Unsolicited pontifications:

1.

I turn the air on prior to the dive. I want the pony in the event of an emergency and do not want to fool with getting it on. Many tech divers will disagree with this statement, but thats my preference.

Ummm, not just 'tech divers' disagree with this statement. The reason why you charge your regulator then turn off the valve is because you're paying extra for this equipment and its maintenance, and carrying all this extra weight, because you believe that in the gravest extreme underwater your life may depend on having that gas available. The reason why you might need it is because dives don't always go exactly as you expect them to go. That includes emergencies - they rarely occur with the choreographed precision that you experience when you practice your 'out of air drills' at your local dive site. Real emergencies are almost always more interesting.

So, when you absolutely need that gas, it would be discouraging to discover that while you were flailing around stabilizing some 'issues', you experienced a free-flow that bled off 90% of your small 'redundant air source'. It really sucks when that happens. To prevent things like that you turn the valve off - thereby ensuring that a free-flow doesn't eliminate your redundancy. At the very least, you ensure that if you DO have a free-flow you can reach and turn the valve off to stop it - but with only 13 cu ft to begin with its a moot point. Do you know how quickly a free-flow can empty a 13 cu ft tank at depth?

By all means, dive any way you want to. But bizarre things happen, and a free-flow off your redundant tank valve will eliminate that option. If the free-flow occurs as a result of some underwater flailex, it might just ruin your entire day.


2. When you're involved in responding to an underwater emergency, most people's respiratory rate accelerates. Regardless of what your SAC rate is normally, it may be a tad higher when life gets interesting. Using 1.3 cu ft per minute might be a good idea, to calculate how much gas you might need to bail out of a situation. You might use 100' for a depth, because lots of recreational dives get that deep, and because its pretty easy on the math - at a standard ascent rate of 30 ft per minute it will take you 3 minutes to ascend to 10'. So...assume you have some 'issue' at 100'. Lets give yourself 2 minutes to respond to whatever the issue might be, after you do the gas switch to your redundant gas source. Then add 3 minutes to ascend from 100' to 10'. Then a 3 minute safety stop because you were at 100' for several minutes - perhaps longer than you planned, with the situation. Then another minute to surface slowly. That's 9 minutes for the response and ascent at 1.3 cf/min consumption rate, or a requirement for 11.7 cubic feet of gas. Will your 13 cubic foot tank be adequate? If its full, and if your consumption rate doesn't exceed 1.3 cu ft/min, and if you can get untangled from whatever in 2 minutes, etc. then yes it likely will. Do you want to cut things that close? All these are things that only you can answer, but if you're going to carry redundant gas anyway, you might want to spend some time playing around with scenarios.

Don't just decide on a solution and proceed under the illusion that you are now safer. Spend some time chalk-talking emergency response with your buddy, and working with the gear so that you know its capabilities and requirements. Hope this helped.

Regards,

Doc

 

[mdsd]

re: makosince70
great feedback, i'll check the quick draw
i agree with "air on" and the 2 lbs, sounds right

i'll need to think about the regs and gauges etc, any other thoughts out there?

 

[mdsd]

Permit me a few brief observations:

1. Pony Tamer is a pretty good option.

3. You don't need a pressure gauge on a 13cf tank. Once you go on it you're going up. You'd better know there's enough gas in it to allow you to surface at a leisurely pace. If you don't know that, you'd better sit down and do some math.

Doc

Thanks,

1. I'll check out the pony tamer too.
3. Skip the PG.

Good points about the free flow scenario. I did not consider that, ie, losing air on the way down or at depth. I think 13 cf is plenty for an ascent from 100ft or thereabouts.

 

[Scubakevdm]

3. You don't need a pressure gauge on a 13cf tank. Once you go on it you're going up. You'd better know there's enough gas in it to allow you to surface at a leisurely pace. If you don't know that, you'd better sit down and do some math.

An SPG is very handy for telling whether or not you are about to jump into the water with an empty or partial pony though. I suppose you could get a tank checker, but I like the ease of an SPG for about the same cost. You can get an 8" HP hose for it and bungee it to the 1st stage to keep it out of the way.

 

[Doc Intrepid]

I'd just throw my primary first stage on it to check it, and save myself the extra $$!
('Course you could also buy an aluminum 30, throw an SPG on it, sling it like a stage or deco bottle, and have something thats way more useful, too! )

 

[mdsd]

FYI

Found another pony mounting bracket at http://www.sealifescuba.com/

 

[paulwlee]

When I was still using a pony tank,(I now dive doubles so don't use one) I searched a lot for a good pony bracket and found the Tigermount. I feel that it's the best you can get. Look at www.tigergear.com.

As for the regulator, I suggest getting something like the Oceanic Alpha. Simple, dependable, affordable, and with pretty good performance that rivals some more expensive regulators. For the SPG, the mini SPG should be fine. Since it's for emergencies, you really don't need to check the pressure during the dive. But having that mini SPG on the regulator is convenient since you can check the pressure when you hook up the regulator before the dive without hooking up another regulator.

 

[liberato]

The Quick Draw bracket from Ultimate Products Corp mentioned already is definitely the most elegant solution if you want a tank mount style and don't have budget concerns. It is particularly nice because there is no attachment to the main tank so it can be swapped out easily.