Looking to reduce weight on land.

[WD8CDH]

Originally Posted by mitsuguy

its a cool system, but they sell weights to make the assembly less positive, neutral, or negative...

out of the water, the tanks will be much lighter than standard gear, however, the weight you need to add will be similar to an aluminum tank to stay neutral in the water... this is both good and bad - it doesn't solve the root problem, walking with gear on is heavy, but it does make moving the tank around by itself easier...

Not quite true, when you add the weight they will still be much lighter than aluminum tanks, they are still lighter than even HP steel tanks of the same capacity.

[mitsuguy]

Originally Posted by WD8CDH

Not quite true, when you add the weight they will still be much lighter than aluminum tanks, they are still lighter than even HP steel tanks of the same capacity.

Lets see if we can do some math and stop guesstimating...

their 6.7 liter setup, even at 300 bar, is only 71 cu ft.

if I am reading this correctly, an empty tank setup weighs 27 lbs, and a full tank setup weighs 37.7 lbs... which is confusing, because 10 lbs should be around 133 cubic feet... so, if we were to assume that 6.7 liters doubled up, you would get roughly 130 cubic feet of air, then we are doing pretty good, assuming you could find someone to fill it to 300 bar to start...

You could get a PST 130 cu ft steel cylinder (I can't compare it to aluminum, as the biggest AL cylinder I see is 100 cu ft), which weighs only 43 lbs and never goes positive no matter how empty you get it...

I'd just like to know the actual buoyancy characteristics of those tanks, and being as how I don't see them published, its hard to say for sure