Pony Bottle usage

[Maule]

I'm curious out of the people that own a pony bottle what size they purchased. Also, what percentage of the time do you take it with you on a dive? Are you glad you purchased it or is it so much hassle that you find yourself not equipping it on your dives? Do you only use it for certain depth dives and if so what is your limit not to use/ or to use.

 

[fire_diver]

Welcome to Scubaboard. Not to belittle your question, I think it is a very valid one; but you might try to do a search under "pony" here on SB. This has been discussed ALOT even in the last couple weeks. If you don't find your answer this way, let us know, and we will be happy (most of us) to start another thread that last 500 pages and digresses into a battle of ideologies. We love doing that sort of thing here.

FD

 

[texdiveguy]

I'm curious out of the people that own a pony bottle what size they purchased. Also, what percentage of the time do you take it with you on a dive? Are you glad you purchased it or is it so much hassle that you find yourself not equipping it on your dives? Do you only use it for certain depth dives and if so what is your limit not to use/ or to use.

You asked a question and deserve an answer!

I use a Al19cf pony bottle in rec diving when on any single tank solo runs or deeper dives. Not a waste of money, and very easy to rig and sling.

 

[Dave in PA]

My first pony was more like a quarter horse: Al40 slung. My second pony was the same. I don't dive them every dive, but when going deep or staying long, I will carry one. I like it, The only regret was not going with DiveRites for both bottles. I usually have 40% or better Nitrox in it.

 

[c555]

My first pony was more like a quarter horse: Al40 slung. My second pony was the same. I don't dive them every dive, but when going deep or staying long, I will carry one. I like it, The only regret was not going with DiveRites for both bottles. I usually have 40% or better Nitrox in it.

Why would you have nitrox in it if you take it on deeper dives. It just makes it useless for where you are taking it. Makes no sense.

 

[Dave in PA]

I use a higher percent O2 on the way up, so I guess it's not really a pony anymore. I guess I should have also mentioned that I also dive doubles...... which is a really good reason to use a 40 cu bottle; if (when) you start doing more technical dives, the bailout bottle becomes a stage/deco bottle with out the expense of a smaller cylinder.

See, fire diver, it started on the first page!

 

[RICHinNC]

Personally, I have a 13 cuft...and I think that is too small. The 19 cuft is just about right and to me, anything bigger is just that...too big. But the reality is, it totally depends on the depths you are diving and what you expect from your pony.,

As to when do I dive it?? All the time. Take it with me on trips.

It is an emergency bail out bottle for ME....not to be handed off. I have an octo for others. It is not to extend a dive. It is to cover ME for a catastrophic reg failure....mine.

 

[Web Monkey]

I'm curious out of the people that own a pony bottle what size they purchased. Also, what percentage of the time do you take it with you on a dive? Are you glad you purchased it or is it so much hassle that you find yourself not equipping it on your dives? Do you only use it for certain depth dives and if so what is your limit not to use/ or to use.

I use a 19' down to about 60', and a 30' down to about 130'.

The gas calculations work out nicely, and the 30 is easily enough gas for a normal ascent and stop from 130' for me. Your mileage may vary, so be sure to do your own calculations.

Terry

 

[fire_diver]

See, fire diver, it started on the first page!

Well, since this has been started lets do this thing right.....

Ok, first off, good job for wanting to get a pony. Next step is to examine what diving profiles you plan on using it for.

You should be using it ONLY for a bailout bottle (unless you are doing staged deco).
Next step is to look at how deep you plan on diving now, and farther down the road.

Next step is to use your gas planning skills. For those new enough to not understand gas management, here are a few rough numbers....

to simplify things, we will assume that a stressed diver is using 1cf/min @ 1ata. If you are an air-hog naturaly, double these numbers.

diver spends 1 minute to sort out problem at depth.
ascent rate is 33ft/min
safety stop for 2 mins at 16.5 feet (1.5ata, again to simplify)

lets start with a basic rec diver, diving to a max of 66ft

sort things out: 3ata (66ft) for 1 minute = 3cf
ascent to 16.5ft = 2min at average depth of 2ata ((3+1)/2)= 4cf
2min stop at 1.5ata = 3cf
total needed gas is 10cf.

now again for 99ft or AKA 4ata
sort it out = 4cf
ascent = 7.5cf
stop = 3cf
total = 15cf

Now, if you like to do longer safety stops (and you should be doing more than 2 mins) add that extra time into the mix. Ever any hint of a possibility that you and your buddy might both need to use that bailout? double those numbers.

Once you know what diving you will be doing, you can figure out what size pony to buy. You should also have a 'fudge factor' thrown in to the pony size selection. If your ascent is a tad too slow, you will go OOA again. Also, you don't want to suck a bottle dry, always leave SOME pressure in it if you can.


Now, to start the real debate....
I say you need to sling that pony like a stage, keep the valve turned on, and don't use those tiny, unreadable "pony gauges" use a full size pressure guage.

FD

 

[Packhorse]

I use a 19' down to about 60', and a 30' down to about 130'.

The gas calculations work out nicely, and the 30 is easily enough gas for a normal ascent and stop from 130' for me. Your mileage may vary, so be sure to do your own calculations.

Terry

Im quite interested in your calculations.
By mine a 19cf will return you from 130ft at an ascent rate of 33ft/pm and a 3 min 15ft stop with a 1cf/pm SAC.

There for I belive a 19cf is a great size for any rec dive.
But if you are looking at going tec in the future a 40cf may be a better choice.