Buoyancy vs trim vs BCD vs Wing

[Kermit]

I use a wing but, for buoyancy there's not a lot of difference between a wing and a bcd until you start carrying a lot of gas. The concept is to be neutrally buoyant at 3m with an empty tank. Extra gas needs to be added to compensate for the weight of gas you start your dive with (about 2kg of air in a full 12??) and the compression of a neoprene suit (drysuit or wetsuit) at depth.

I use a membrane drysuit and find that I can adjust my buoyancy when using a single cylinder quite comfortably just adjusting the amount of gas in the drysuit, other people use a constant volume drysuit and adjust with a bit of gas in the wing/bcd. Either way is suitable as long as it suits you.

The point is there aint a lot of gas in your wing/bcd even if you are using it as your sole method of buoyancy adjustment. With me, there is no gas in my wing unless I'm sitting on the surface. If you still have gas in your wing/bcd with an empty tank at 3m then you are overweighted.

Trim is a different thing completely. This depends on WHERE the weight is situated. Moving your tank up and down in the straps has a large effect. Also, think about where your weights are situated. For me, I have weights in a pouch by my belly and some strapped to my tank. This is just a personal thing, the important thing is that I know exactly where to position my tank and weights to get the trim I want and I make sure everything is in the same place (exactly) whenever I dive.

An underwater camera is a very handy tool. How you feel your trim is in the water can be very different to how it actually is as shown on a camera.

Best of luck,
kind regards
Ian

[o2dependant]

Thanks all!!

I think I will go with the wing as even though I did use it a handfull of times I just felt like we had a better connection.

Once I get all my gear I will likely get a day in with somone who can help me fine tune things.


Was not aware of the friday ruckus!!

[Graham Smith]

Was not aware of the friday ruckus!!

It's an old tradition from "The other place". There are some fairly contentious topics such as using a Pony, Wing v BCD, BCD v Drysuit for buoyancy, and many others.....All guaranteed to start up a heated debate otherwise known as "The Friday Ruck".

This thread (and topic) looked an ideal candidate for a Friday....

G

[Regthing]

A wing and back plate is also good as the weight of the back plate will replace some of your lead, for dry suit diving get stainless steel, not aluminium. It also places the weight higher up your body and closer to your centre of gravity.

There are also weights available that fit in the groove of the back plate, between twin sets, in pockets on can bands etc that allow you to position the weight where you need it to achieve the trim you want.

[ootini]

I now dive a plate, oph, wing and twin 12s. In fresh water I need no extra weight, in salt I stick two small shotbags in pockets on the waist band. I love the lack of clutter and shit in front of me when using a wing/oph compared to a traditional bcd.

[Nitnab Nhoj]

The air in a jacket-style BC or a wing-style BC goes to the same place when the correctly weighted diver is horizontal ie. the highest point behind the shoulders. The flotation low down in a jacket-style BC only comes into effect when the diver is horizontal with it fully-inflated at the surface. Sounds like the OP needs to look at the position of his ballast rather than the BC.

[Mike Ward]

FWIW, if you're also diving in a shorty the bare legs will be less buoyant than legs clad in neoprene, the reverse of floaty feet in a drysuit.

[sheesh]

If you can get ankle weights is there anyone who does ankle floats?

[Mike Ward]

Some of that thick foam pipe lagging?

[o2dependant]

FWIW, if you're also diving in a shorty the bare legs will be less buoyant than legs clad in neoprene, the reverse of floaty feet in a drysuit.

Interesting. This was actually in a 3mm shortie( and a first and only). Usually I'm in a full suit. Was weighted properly I checked in and out