Proper Weighting w/ Pony Bottle

[limeyx]

You *guess*? Have you ever even dove with a pony? Tell you what, throw your pony rig in the ocean and see how positive it is. None that I know of are positive.

Mine stays full, and I rarely use it, and when I do, it's only for drills. If the emergency ever arises, I'll deal with being a pound or two underweighted.

I meant when they are empty. My AL40 deco bottle gets maybe +2 when fullyempty and so a 19 or smaller should probably be less positive.

Only way to tell for sure is to get in the water and do a weight check. Anything else is guesswork.

 

[srownin]

I definitely want to gauge the negative buoyancy of my pony when full. I, like a few others here, will only use my pony in an OAS and when doing drills. That being the case, if I am using my pony, I am going to the surface too, so I do not really mind beinig underweighted as I use the air.

There happens to be a great article on proper weighting in ScubaDiving this month. I am going to try some experiments in my bath tub to get an idea first. After that, my brother and I are going to experiment with the techniques described in the magazine at the quarry in a few weeks. I will report back any interesting findings.

--Scott

 

[srownin]

OK. I decided to take a look on the web for some info. I found, on the luxfer Web site, the data I was looking for.

My tank is a 13 cu. ft. pony. According to their Web site it should be -1.71# buoyant when full, and -0.72 empty.

The scubadiving article puts a reg and console at 1-2 pounds negative. Since I have a reg and pressure guage on my pony, I am guessing another 1.5 negative.

If your curious, check out luxfer.com, go to scuba cylinders and the product specs.

--Scott

 

[Tagerisatroll]

The luxfer page is a good starting point but you'll need to tune your setup, I found myself to negitive just using their numbers, with my new Luxfer al100. but it was alot larger tank

 

[all4scuba05]

gee, I wonder if handing off you pony to your buddy changes anything?