Pony/Redundant Set-up
- Thread starter CavemanScuba
- Start date
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OP
CavemanScuba
Contributor
OP
CavemanScuba
Contributor
Crush
Contributor
For me a 19 cu ft pony is a bail-out device and does not form part of my air management strategy. I haven't had to use the pony yet (save for practice) and hopefully never will. If I do need it I would like to think that using it twice in one day on back-to-back dives would be highly unlikely. In any event, a transfer whip will allow you to top up a 19 cu ft between dives.
I am not saying that there is anything wrong with a 40, however.
GrumpyOldGuy
Contributor
Here, I will offer my 2 cents. I don't mean to pick on Elan, but I think we can discuss differences of opinion without pissing on each other as it tends to happen with some others zealots on pony bottles.
If you assume the diver stressed and consuming 1 cu/ft per minute and wants time to work things out on the bottom and do all deep and safety stops, then you are correct that a 19 is not big enough at 100'. This is a big issue with pony bottles, unless you know your SAC and have a pony ascent plan in place, then the size increases insanely as you add all the extra buffers such as fumbling around at depth for a minute to "work things out".
However, if you know your SAC and practice with the pony on a regular bases, the amount of air needed is much less. I personally can do all my stops from 100' on a 6 cu ft bottle, now don't read this as an endorsement of 6cu ft for a 100' dive as that is under ideal conditions and no tolerance and could get you killed, just saying that a 30 may be overkill IF YOU PRACTICE AND KNOW YOUR AIR USE FOR ASCENT.
First, if I bail out on a pony, my diving is done for the day, maybe a lot longer. A major issues happened and I will not continue to dive until I understand why it happened and have some serious soul searching. No reason to plan a pony big enough to allow me to screw up 2 sequential dives.
The is some logic to buying a 40 for use as a stage, as long as you don't plan on traveling by air with it. I own 3 pony tanks including a 40, different sizes for different uses.
I agree, its not a cost issue. If the 40 works for you (meaning you don't travel by air and don't mind the extra size and weight (topside) fine. Once you set up one size to sling, you can add another bottle cheap enough later if you want more flexibility.
Not always true, many systems connect to the tank bands with quick releases. So if you need to swap tanks, its 30 seconds or so. Plus many larger boats have compressors depending in your location, so the whole tank switch becomes moot. My mounting hardware for back mount was about $25, so the cost is about the same as stage rigging.
If you assume the diver stressed and consuming 1 cu/ft per minute and wants time to work things out on the bottom and do all deep and safety stops, then you are correct that a 19 is not big enough at 100'. This is a big issue with pony bottles, unless you know your SAC and have a pony ascent plan in place, then the size increases insanely as you add all the extra buffers such as fumbling around at depth for a minute to "work things out".
However, if you know your SAC and practice with the pony on a regular bases, the amount of air needed is much less. I personally can do all my stops from 100' on a 6 cu ft bottle, now don't read this as an endorsement of 6cu ft for a 100' dive as that is under ideal conditions and no tolerance and could get you killed, just saying that a 30 may be overkill IF YOU PRACTICE AND KNOW YOUR AIR USE FOR ASCENT.
First, if I bail out on a pony, my diving is done for the day, maybe a lot longer. A major issues happened and I will not continue to dive until I understand why it happened and have some serious soul searching. No reason to plan a pony big enough to allow me to screw up 2 sequential dives.
The is some logic to buying a 40 for use as a stage, as long as you don't plan on traveling by air with it. I own 3 pony tanks including a 40, different sizes for different uses.
I agree, its not a cost issue. If the 40 works for you (meaning you don't travel by air and don't mind the extra size and weight (topside) fine. Once you set up one size to sling, you can add another bottle cheap enough later if you want more flexibility.
Not always true, many systems connect to the tank bands with quick releases. So if you need to swap tanks, its 30 seconds or so. Plus many larger boats have compressors depending in your location, so the whole tank switch becomes moot. My mounting hardware for back mount was about $25, so the cost is about the same as stage rigging.
Oh the ride the pony issue...Well my 5¢ worth, cause I am Canadian eh...
I use to back mount a 30 to my 80. I had a 5 foot alternate which I tucked into surgical tubing around the tank and was neatly stowed under my left arm. I used pony tamers to attach the 30 to the 80. Once I mastered the position of the 30 and balanced my weight, the turtle factor, was a non issue. ( sometimes mounting a secondary tank off centers your balance which makes you roll on your back as you swim ).
I then switch to a DIR slung rig. I use to have a Zeagle ranger and found slinging the 30 was uncomfortable. I then switched to a back plate and wing and found slinging a redundant gas supply was better this way.
I have to add that a 19 is not adequate gas for a 100 foot bail out. A 30 is the bottom line minimal for a recreational dive. Adding a large tank above an alu-80 should also be considered if one tends to go deeper that 80 feet.
I follow a rule of thumb for this. anything below 80 I use a 40 redundant, plus either a 98, 100 or a 130 or use a set of doubles. This is based on a recreational dive where no deco is planned. Anything above 80 feet I use an Alu -80 or a 98 without any redundant gas. I rely on a competent buddy most of the times. I say most because on occasion I dive with strangers. I will then consider a back up plan where I will bring a redundant gas supply.
Also take note. Your back up PONY should be considered in your gas management system. You need to factor this in when planning your dive. For both you and your buddy. This is all part of good diving prictices and good gas management. Knowing your SAC rate is key in proper gas planning.
Now consider why you need this redundant gas. Plan you dives accordingly. If you follow your plans and dive with in your limits and training, you will see that a redundant gas supply is not needed. A good buddy will always be with you. So plan your dive and dive your plan, dive with in the limits of your training. Use a rule of 1/3 to plan a recreational dive. This rule is the most basic rules of gas management. 1/3 down, 1/3 around and a 1/3 out. I am repeating myself, Knowing your SAC rate - you can adapt this rule to the type of dive you will do that day.
If you dive solo - then this is a whole other topic.
I use to back mount a 30 to my 80. I had a 5 foot alternate which I tucked into surgical tubing around the tank and was neatly stowed under my left arm. I used pony tamers to attach the 30 to the 80. Once I mastered the position of the 30 and balanced my weight, the turtle factor, was a non issue. ( sometimes mounting a secondary tank off centers your balance which makes you roll on your back as you swim ).
I then switch to a DIR slung rig. I use to have a Zeagle ranger and found slinging the 30 was uncomfortable. I then switched to a back plate and wing and found slinging a redundant gas supply was better this way.
I have to add that a 19 is not adequate gas for a 100 foot bail out. A 30 is the bottom line minimal for a recreational dive. Adding a large tank above an alu-80 should also be considered if one tends to go deeper that 80 feet.
I follow a rule of thumb for this. anything below 80 I use a 40 redundant, plus either a 98, 100 or a 130 or use a set of doubles. This is based on a recreational dive where no deco is planned. Anything above 80 feet I use an Alu -80 or a 98 without any redundant gas. I rely on a competent buddy most of the times. I say most because on occasion I dive with strangers. I will then consider a back up plan where I will bring a redundant gas supply.
Also take note. Your back up PONY should be considered in your gas management system. You need to factor this in when planning your dive. For both you and your buddy. This is all part of good diving prictices and good gas management. Knowing your SAC rate is key in proper gas planning.
Now consider why you need this redundant gas. Plan you dives accordingly. If you follow your plans and dive with in your limits and training, you will see that a redundant gas supply is not needed. A good buddy will always be with you. So plan your dive and dive your plan, dive with in the limits of your training. Use a rule of 1/3 to plan a recreational dive. This rule is the most basic rules of gas management. 1/3 down, 1/3 around and a 1/3 out. I am repeating myself, Knowing your SAC rate - you can adapt this rule to the type of dive you will do that day.
If you dive solo - then this is a whole other topic.
OP
CavemanScuba
Contributor
To answer the whole issue....I want to do some ice diving but I feel I need a redundant for this purpose. Therefore that is the reason for my inquiries.
Crush
Contributor
Strongly consider getting proper training and don't just follow someone on a trust me dive.
OP
CavemanScuba
Contributor
well before you get into the ice diving. You are on your way to gaining knowledge regardless of some of the opinions or non opinions you will get.
Ice diving is a whole other issue. You will - I am certain, take an ice diving course. You will learn the ins and outs and you will then see what gear is needed. SO before you think you many need this or that. Ice diving is a whole whack of logistics, alot more extra gear than you realize. Its the small things you tend to forget. Since this is an overhead diving environment. A redundant gas supply is your least concern. Your main concern with ice diving is free flow, multiple free flows, gear failure, cold and then air supply. I say this from experience. Yes redundant gas is a major concern however it is not at the top of your list of issues to deal with when ice diving.
Again keep exploring your gear options, but get into an ice diving course, you will have a better perspective of it all.
Enjoy my friend. Safe dives
Ice diving is a whole other issue. You will - I am certain, take an ice diving course. You will learn the ins and outs and you will then see what gear is needed. SO before you think you many need this or that. Ice diving is a whole whack of logistics, alot more extra gear than you realize. Its the small things you tend to forget. Since this is an overhead diving environment. A redundant gas supply is your least concern. Your main concern with ice diving is free flow, multiple free flows, gear failure, cold and then air supply. I say this from experience. Yes redundant gas is a major concern however it is not at the top of your list of issues to deal with when ice diving.
Again keep exploring your gear options, but get into an ice diving course, you will have a better perspective of it all.
Enjoy my friend. Safe dives
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