Pony bottle - what size?

[SCUBA482]

I dive in generally good conditions. I was trained to CESA from 60' in the 70's, and I do still practice CESA's (but not often enough) from about 40' these days... so my personal "safe depth" is about 40-50 feet. I won't go below that depth without redundancy (or a buddy!).

I couldn't agree more with practicing your skills to know what your own personal "safe depth" is. I too feel anything below 40-50 feet makes me more desirious of toting my pony along.

 

[DareDevil]

(OT) I logged a while ago, but I stopped posting for a number of reasons. Well, time to come back (OT)

I do many solo dives (around 30%) and since I dive mostly in Summer/Spring the first solos are always aimed to check the equipment (Regulators, BCD, weights ...) and the diver (how I feel underwater, buoyancy control, breath frequency ...). Other solos are for the fun of it, but never below 30m (~100 feet) and rigorously no-deco.

I have never (so far) used a Pony Bottle. That does not mean I consider a Pony useless, and I am posting just to talk about it.

My take is simple: considering the redudancy level of the equipment (two separate regulators, computer with air sensor + analog manometer, watch and tables) and the context (max 30m depth / no deco) I can't see how a third regulator and a pony would change the odds.

This is maybe due the fact I fail to envision a scenario where both regulators would stop providing air and therefore making it impossible to execute a controlled ascend to the surface. Even with one of them going free-flow, it would be still possible use the other.

I have experienced A SINGLE regulator failure a couple of times (free-flow, mouthpiece disconnecting) and that was an extremely rare event, but never experienced or even seen a double failure.

The only thing I can think about is to have BOTH tank valves not fully opened and therefore stopping to provide air at a certain depth. But if a diver does that to the main tank, he could do that as well on the Phony.

Regards,

DareDevil

 

[b1gcountry]

My take is simple: considering the redudancy level of the equipment (two separate regulators, computer with air sensor + analog manometer, watch and tables) and the context (max 30m depth / no deco) I can't see how a third regulator and a pony would change the odds.

This is maybe due the fact I fail to envision a scenario where both regulators would stop providing air and therefore making it impossible to execute a controlled ascend to the surface. Even with one of them going free-flow, it would be still possible use the other.

Regards,

DareDevil

Unless I'm looking at the wrong picture, the OP has a reg with two second stages, but there is only one first stage. They are both connected to the same first stage. If the first stage has a nasty failure, or the tank empties, that is going to kill both second stages. If you have a second freeflow, you can breathe off of it just fine. I'm not sure if you understood the scenario correctly. Either that, or I am misunderstanding something.

To the OP: Why are you using this 'vintage' gear? If you are a gear head, or you just want to see if it works, that's one thing. If you are trying to nickel rocket dive equipment for solo, I would recommend another way. Older regs can work just fine if you know your thing, or get them serviced by someone who does. Or they can be terrible, and untuned POS.

I would suggest looking into maybe a new SPG. I don't know many people with old school SPGs like that one, which makes me suspicious if they aren't around anymore, do they tend to fail. Maybe not, but something to look into.

If I had it to do again, I wouldn't have bought my 19cf pony bottle. I would have either gone with a 40cf bottle, or just a little 6cf bottle for shallow ascents. That way I wouldn't have a 19cf bottle sitting around unused for the last two years.

Tom

 

[DareDevil]

Hi Tom,

I wasn't speaking about the need of a Pony for the OP. I was merely thinking about the need of a Pony in the context I depicted (solo, max 30m, no-deco) and with the equipment I described.

IMHO, the OP to increase solo safety should consider first other options (a watch, a manometer, tables, better regulators, better BCD, ...) before thinking about a pony.

DareDevil

 

[A34735]

Forgive my ignorance, but what is 'CESA'? Free ascent?

 

[pdelannoy]

Relative to the original question regarding the pony. I solo dive at my local site more than I buddy dive. I use a 19 pony with its own regulator and pressure gauge. I chose the 19 based on my sac and the possibility of ascending slower than 30 ft/min with a 3 min safety stop at 15 from a depth of 100 feet. 100 feet because that is the average deep depth of my deepest dives at the local site. I train with with my pony and making the ascent I describe herein. I think that if you solo dive often that it is a good idea to have the second independent system.

PD

 

[walke121]

controlled emergency swimming accent. To the OP's question I have a 40 CF bottle that I use when spearfishing. I usually have another 40cf bottle with 100% O2 at about 15 ft under the boat.

 

[Jorgy]

I dive a 19 CF pony.........mostly for dives with "insta buddies"........

When I am with my regular buddies I rarely take it...........

I don't solo dive.........

Calcs said 19 CF would be enough air for recreational depths..........

If I were to do it again I would go with a 30 CF.........

I sling my pony, the difference in size/weight going from a 19 to 30 in negligible.....

Cost is about the same........

Way more air…………

Hope this helps.........M

 

[DeepSeaExplorer]

I would forgo the pony bottle and use the money to upgrade the reg, since you're more likely to have issues with a 30 year old reg.

 

[Apecks]

Here is my new setup:-

Catalina 40L
Apecks US4 Din First Stage
Apecks Pony Guage
Apecks XTX reg
OMS Rigging Kit