6cuft pony how negative??

[domino22]

How negative is a 6 cuft pony bottle with full air with a oms 200 din valve? Anyone know? Thank You

 

[Otter]

You could fill a bucket full of water. Stick the tank in and capture the displaced water. Weigh the water and then weigh the tank. Then you would know fo sure.

 

[domino22]

That sounds like a good idea I will give it a try. Thanks

 

[OneBrightGator]

it won't make much difference with only 6 cu. ft. but I'd do it with only a little pressure in it, not full.

Ben

 

[domino22]

OneBrightGator once bubbled...
it won't make much difference with only 6 cu. ft. but I'd do it with only a little pressure in it, not full. Why because displacement is due to volume and not the weight in the volume of the tank?

Ben

 

[Doc Intrepid]

-1 lb full in salt water.

Here's a link that may be helpful:

http://divesales.com/tanks/index.html

scroll down, you'll see all their (Luxfer) tanks with weights full and empty (except the 6). The 13 is ~ -1.71, ergo the six is likely to be somewhere between 60% to 70% of that (1.02 to 1.19 lb) as much of the weight's in the valve and the valve is the same.

Likely good enough for weight planning, unless you're going to weigh your knife, wetnotes, etc.

Best,

Doc

 

[OneBrightGator]

domino22 once bubbled...
why?

Well, it's honestly being way too nitpicky, but you should have enough weight to hold yourself at 20' with 500 psi in your tanks, so in your worse case you'd have nothing in your backgas and 500 psi in your pony, but with only 6 cu. ft. we're probably talking about insignificant swing.

Ben

 

[domino22]

Doc Intrepid once bubbled...
-1 lb full in salt water.

Here's a link that may be helpful:

http://divesales.com/tanks/index.html

scroll down, you'll see all their (Luxfer) tanks with weights full and empty (except the 6). The 13 is ~ -1.71, ergo the six is likely to be somewhere between 60% to 70% of that (1.02 to 1.19 lb) as much of the weight's in the valve and the valve is the same.

Likely good enough for weight planning, unless you're going to weigh your knife, wetnotes, etc.

Best,
I was asking for weight planning. I will use it under my right arm attached to BP. I guess the weight is so small I will concider it as a non factor. Thank you.
Doc

 

[Doc Intrepid]

under your left arm, not 'right' arm.

You attach the 6 to the bp under your LEFT arm.

Keep your right arm unencumbered.

Here are a set of straps that work real well for that purpose (scroll down mid-way: 'argon inflation system', etc.):

http://www.halcyon.net/exposure/accessories01.shtml

Regards,

Doc

 

[Genesis]

The 6cf bottle as a bailout is pretty marginal.... especially if you're diving fairly deep.