BCD question.

[rnln]

Hi everyone,
I am new to this board and this game so I am reading all over the place and still not very clear. My first question about BCD is the lift capacity. I have seen people posted as low as 17lbs and as high as 45lbs. So, choosing a BCD, or wing, is it that I have to choose one which works with my own weight? Can someone please explain?
Thanks in advance.

 

[James79]

Hi everyone,
I am new to this board and this game so I am reading all over the place and still not very clear. My first question about BCD is the lift capacity. I have seen people posted as low as 17lbs and as high as 45lbs. So, choosing a BCD, or wing, is it that I have to choose one which works with my own weight? Can someone please explain?
Thanks in advance.

Really depends on a few factors. It has to be enough to float at surface with a full tank, and also maintain neutral at depth. It's counter intuitive, but you may need more lift at depth due to wet suit compression ( the closed cell neoprene compresses under pressure resulting in less buoyancy and you having to add air to the bcd to compensate). Thicker the suit and deeper the dive plan make for more lift required.
Depending on your depth of interest, there is an excell sheet on here that helps with weight and lift requirements, and the instructions explain it fairly well. I'll find a link for you if no one beats me to it.

 

[James79]

Found it
Optimal Buoyancy Computer
There is the thread. Others explain it better than I can!

 

[JackD342]

My simple advice is to have enough lift to float your gear at the surface if you take it off, assuming weight integrated BCD.

 

[Ojai Diver]

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[tursiops]

My simple advice is to have enough lift to float your gear at the surface if you take it off, assuming weight integrated BCD.

Yeah, you want AT LEAST this much buoyancy, or risk watching your BCD sink to the bottom if you need to remove it.

 

[Princess Chris]

To put it simply, lower lift capacity tends to be used for warm water and higher for cold. You need more weight in cold due to a thicker/more buoyant exposure suit therefore need more lift. If you try using a travel bcd with 17lb lift capacity with a semi dry and 22lbs of weight you may not have it for very long should you let it go in the water. However used in the right environment they are very handy. It's all down to what kind of diving you are going to be doing.

 

[happy-diver]

I have seen people posted as low as 17lbs and as high as 45lbs.

In your circumstance 17 is far too low and 45 is far too high for single tank rec diving

Really depends on a few factors. It has to be enough to float at surface with a full tank, and also maintain neutral at depth. It's counter intuitive, but you may need more lift at depth due to wet suit compression ( the closed cell neoprene compresses under pressure resulting in less buoyancy and you having to add air to the bcd to compensate). Thicker the suit and deeper the dive plan make for more lift required.

and this whilst this information is bandied about incessantly
in this context does not apply to one tank recreational depth

 

[rnln]

Thanks everyone for quick answer and document. About the other discussion, manual, and Excel, OMG haha. It would take me many free days to understand. Many terminologies I don't even know what it means yet

Of course I will need to read more and more, but for right now can someone from SoCal tell me the proximate least lift capacity of a BCD or Wing/blader most people get? Should it be possible?

 

[Ayisha]

Approximately a 30 lb (donut shaped) wing is very suitable for all except the largest single tanks. For example, it's perfect for an 80 cf or easily up to 119 cf tank.

A 40 lb (donut) wing is suitable for doubles. Anything with a much higher lift capacity is for exploration diving with multiple tanks, scooters, etc.

No matter what advice you get, no wing is equally suitable for a single tank or doubles.

If the wing is too large for the tank/tanks, it will "taco" around it/them, trapping gas, making it more difficult to release gas, and making you less streamlined and creating drag in the water.

Hope that helps...