Pony Setups

[GLOC]

This is not meant as a troll as I genuinely don't understand having had a fairly short singles diving experience.

Having just read on the 'Customer Service' thread talking about poor service, I have noted that the OP has now taken the octopus from their main cylinder and put it onto the pony. To me this seems daft but that is my viewpoint as I use twins rather than a single and pony, and even if I did use a single and pony, I would keep 2 x 2nd stages on the main cylinder and have a another 2nd stage on the pony.

My reasoning for this is because if my buddy needs the pony, for whatever reason, I don't want him to have my only alternate air supply in the event that I have a 'mare.

What is the normal size of a pony? 3L? It seems that alot of people are using pony's to add some safety factor to dives which are deeper than 20m or so. I just wonder if there is any guidance given from the training agencies as to how long the pony will last on the way up or if it is assumed that there will be no stops, even safety stops, on the way up.

As I have said, I have no experience of pony's having gone from a single to twins very early in my diving career and this would give me a broader view of things, rather than go with the "I'm right, you're wrong" brigade!

Thanks

[colinicky]

How long a pony lasts all depends on your breathing rate .I did a deliberate bail out onto a pony @ 40m once to see how far I got ! My SAC is about 20 when relaxed & under no stress .@ 6m on deco doing nothing & totally relaxed I can get 30-35 minutes from a 3l .
If you have to bail from your back gas to a pony at depth then you are already under an extra work load therefor your breathing rate goes up + the " Oh Sh*t " factor of why you bailed onto your pony .& my sac can very easilly hit 35 Lpm ,which at the surface means from a 3L x 232 bar / 35lpm = 19minutes of gas BUT @ 40 metres my consumption would be 5bar x 35 sac = 175 lpm ! = 4 minutes FFS
So is a 3l big enough ? probably not IMHO

[Ding Dang Doo]

But if you are on a 'bail out' you must consider the dive to be over and start making an ascent - so as you go up, the amount of gas you use from your cylinder gets smaller - so I think that in practice, you would get longer than 4 minutes... I think.

I've just gone to a 'slung' pony set up - my diving is never over 40m, generally less. I have moved my secondary reg to my pony, and adopted a 'long' hose from my primary reg off my main cylinder, to enable easier 'donation' - it also leaves options open to me if I either want to use the pony for my own use, with my buddy using my reg or 'donate' the pony to someone else.

At least I have an option now, whereas diving off a single cylinder, I didn't.

Pete

[Lou]

When I dived a single and pony I limted myself to about 30m. This was the depth that I felt confident I could ascend rom, with a safety stop. I used a pony down to empty on the last dive of our holiday in Canada (it had to be empty to fly so seemed like a good time to try) and it does last suprisingly long.

However, I id keep three second stages for precisely the reasons that GLOC gives. If i lose my main tank, granted, dive is over and I am going up. If, however, I just lose a second stage for whateer reason - failed mouthpiece, wet breate etc, then I can continue the dive on the alternate and still have redundancy for a buddy or myself. It also allows me to back up a buddies redundancy in the event that hyperventilation did cause them to run through their pony too quickly.

For the sake of a single secondary the advantages outwiegh any disadvantages, in my opinion.

[Hazel W]

Like pete I use a slung pony as a "bail out" reserve when diving solo ....twin 10s with my primary on a long hose complete the back set.
in the event I was forced onto the reserve, I would be heading for the surface as quickly as a sane profile would allow therefore would expect to get between 6-10 minutes of breathing as I accended (from 40 ish) putting me hopefully on the surface with time to spare in a no deco dive ( i dont acumulate deco while solo.)
When diving buddied then I do usually take the pony because it forms part of my balance and weight system .. and generally fill it with 50...or 80% to use while on stops....

2p

Hazel

[Garf]

I used to work it out assuming a SAC of 60, as you'd be running a SAC much higher for the first minute until the emergency is controlled and then much lower after that once you have your shit back together. With a pony carrying approximately 650 litres of gas, that's going to give you 2 and a half minutes at 30M. I used to fill it with air so it could be breathed at any depth I was likely to visit.

In my humble opinion, that's more than enough time to notify your buddy of a problem and get ready to air share, or get to the surface on a no-deco dive. You might miss a safety stop, but the pony will get you out of the water alive.

Which is it's only purpose for existence, in my humble opinion.

[tom]

Originally Posted by Lou

For the sake of a single secondary the advantages outwiegh any disadvantages, in my opinion.

Same here. Having two second stages on your main cylinder gives you more options for access to the largest gas supply.

[chas49]

(which of the various pony threads to post on? )

Have just added a (sideslung) 3L pony to my setup (15L main). Currently have three second stages and was considering getting rid of the octo on the main cylinder - but I think I'm persuaded by the arguments above. If I've got it, I might as well take it with me - it's no use in the kit box, if I have an incident under the water!

I'm now thinking of going over to the long hose primary/ necklaced octo setup.

Questions:

(1) Which octo do I necklace?

(2) Where do I stow the other one?

[Muzzer]

Like Chas49 I run a single 15l with two second stages (primary on a long hose, secondary on a short hose neclaced) with a stage-rigged sideslung 3l pony with its second stage bungied to the side.
I used to run the same rig without the octopus on the 15l as I was told by an instructor that it's superfluous (sp?) and an unecessary extra failure point, but I have gone back to three second stages now as it makes more sense (to me anyway ) to have the octopus mainly as AAS for my buddy and the pony for me, plus my regs (apeks tx40's) have the venturi adjustment levers on them so I leave the occy 'tuned down' to help prevent freeflows. An added benefit of having the pony sideslung is that you can hand it off to someone if the need arises.
Seems to work OK for me.

R
Steve

[Lou]

I would necklace the octo on the main tank as per a standard set-up. Stow the pony reg snoopy looped to the pony, just like a stage is arranged. this means that there is no confusion over which reg comes off of what tank.