PST LP 104 -- buoyancy stats

[roakey]

I've been wanting to do that for some time myself, Rick.

Though I thought a fisherman's fish scale would be adequate (tolerates exposure to water, etc.)

Roger

 

[Rick Murchison]

Originally posted by roakey
I've been wanting to do that for some time myself, Rick.

Though I thought a fisherman's fish scale would be adequate (tolerates exposure to water, etc.)

Roger

I use the balance because that automatically applies the correction for the displacement of water by the lead (if I remember correctly lead weighs about 91% in water what it does in air)... saves on the math...
Rick

 

[roakey]

Originally posted by Rick Murchison
I use the balance because that automatically applies the correction for the displacement of water by the lead (if I remember correctly lead weighs about 91% in water what it does in air)... saves on the math...

Ok, I'm confused. If you're looking for absolute buoyancy, or weight in water, using a balance and lead means you'd have to correct for the lead in water.

In other words it sounds like your method would require the "fix."

What am I missing?

Roak

Ps. Nevermind, you're seeing how much lead you'll need in the water, hence using the lead as balance in the water. I'll leave my reply above in case anyone else is banging their head like I was.

 

[large_diver]

OK -- all good points.

I guess this brings me back to reason for getting into this(ignoring for now whether I am overweighted or not).....whether or not a larger tank like this is dangerous for someone in a wetsuit.....

I am a wetsuit diver for now. Drysuit someday. Single tank diving only.

Lets say that I need 40-45 lbs of total negative buoyancy.

Let's assume I'll be wearing a BP/STA with about 10lbs of negative buoyancy. Let's also assume I'm using an LP 104 or LP 95 with ~ 10-12 lbs of negative buoyancy. Why a 95/104 -- I would like to buy an "all purpose" tank that I can use for both shore and deeper diving.

In a wetsuit scenario, that is a lot of non-ditchable weight. A drysuit would provide redundancy if my wing failed. I do carry a Halcyon closed curcuit surface marker with 40lbs of lift that I suppose could also be viewed as redundancy in an emergency (although this can't be deployed very quickly).

Am I going to die......constructive responses welcomed.

 

[Mverick]

Boy your leaving yourself wide open for one of those smart comments and I'm biting my lip right now.

How much weight do you need to get down in just shorts and a T-shirt? Over the amount you need to get down in that wetsuit. That will tell you more about what you would need to drop at depth.....

But to be honest. You should probably just buy an Luxfer AL 80. That is an alpurpose tank. Use it for a stage tank later. And I'd buy a PST 104 there galvanizing is better than others. It's a nice size tank to.

Unless you get a great deal on some HP 100's like abysmal is offering. I bought a bunch and I love the one's I have already. But I dive dry.....

Can't hold it anymore.
Yes, someday you'll die............. No matter what tank you buy......

Sorry, couldn't hold it.........

Oh, and you're not supposed to use a Stainless backplate diving wet either. If you would go to an AL you would have another 5lbs of drop weight......

But I do........ SST backplate that is. When I use a HP100 and shorts and a t shirt..... No drop weights.......

 

[metridium]

Originally posted by Mverick
Oh, and you're not supposed to use a Stainless backplate diving wet either.

Even with AL tanks? In a 3mm, I still need 9lb or so with an AL80 and a SS backplate.

I wouldn't dive that configuration with an LP 104, though.

 

[Uncle Pug]

Originally posted by Mverick
Can't hold it anymore.
Yes, someday you'll die............. No matter what tank you buy......

Sorry, couldn't hold it.........

I can't hold it either....
I have a remedy for that....
PM me and I'll give it to you....

 

[tivey]

send a request to tivey@pressedsteel.com

 

[goatboy_k]

i dive old PST 104's with a 2 mil shortie, Fred T 1/4 inch stainless BP (12 lbs) , 45lb oxycheq wing, and no weight belt all the time. Plus whatever im carrying. It works great for me. I dive in freshwater mudholes of the midwest. And i can swim it up if i have to.

kurt

 

[fgray1]

There are so many factors when deciding on tanks and how much weight you will need. Here is what to do. Buy a neutualy bouyant tank record your dives , try differant weight at differant depths. That way you can calculate the proper weight for the dive you'll be doing. Make a chart and include it in your dive plan. All equipment is differant . Find what works for you with your equipment. Salt water will be completely differeant than fresh.
Set your configuration and stick with it.