halocline
Contributor
Is a bp/w setting usually require lesser lift capacity? 30lb will be a suitable choice?
- Another question about lift capacity, will water temp affect the need of lift capacity? (I mainly dive in hot/warm water, in 3mm wetsuit) ....
- back pad necessary? will metal back plate be uncomfortable?
Sorry for so many questions. (Clearly I am now turning my head to bp/w)
Sometimes a BP/W does require a little bit less lift because there is less inherent compressible buoyancy than with a typical padded jacket BC. So you need less compensation due to buoyancy loss at depth. But not much; in general many warm water divers dive with much more lift than they actually need.
Cold water means thicker wetsuit, which means more compressible material that loses buoyancy as depth increases. As such, you need more weight to get down, then more lift to compensate for the greater amount of lost buoyancy due to wetsuit compression.
Don't forget, every diver (except sidemount divers) already has a big metal cylinder on their back, the tank. Because the point of contact with the diver's back is only a thin line down the middle, there is very little stability, and when the tank does press against your back, it does so in an uncomfortable manner. The rigid plate spreads out the point of contact over a large portion of your back; this radically increases the stability and any pressure from the tank is spread out evenly. This is far more comfortable, to me anyhow, than the tank being fastened to the diver with soft material.
I realize a portion of scubaboard users get tired of hearing about the wonders of the BP/W and the horrors of the jacket BC. But, this is one of the few areas of scuba gear where it really makes a difference in diving enjoyment, and the general dive gear/recreational instruction industry has it dead wrong. A lot of scuba gear sales are based on hype and gimmickry. For example, regulators haven't really improved in decades despite multiple claims of new and improved wizardry.