First BPW - Basic Questions

[Mr Carcharodon]

for warm water I would suggest an aluminum backplate

Best wishes.

For warm water don't go with both a steel backplate and a steel tank or you will end up overly negative and end up having to compensate with a big wing. If your wing fails then what? A much cleaner solution is to have an aluminum backplate or aluminum tank for warm water. A extra backplate is a pretty trivial expense compared to the cost of travel to a lot of warm water destinations.

 

[Mike126]

Mike, Tobin has mentioned many times that a wing should be able to float your rig at the start of the dive and compensate for changes in wetsuit buoyancy during the dive. I know I am probably in the minority but I would prefer to go to the next size higher if I am on the border line regarding lift. You also need to remember that wing lift is measured with the entire wing submerged. When you are floating on the surface the wing is only partially submerged.

Agree, if I am boarder line I should go higher. Better to have a little too much than too little. I guess I'm confused on the what the lift is trying to accomplish. Shouldn't the wing be able to float your rig and the yourself?

If your numbers are correct, for warm water I would suggest an aluminum backplate and AL80 tank. I believe the "head weight" thing is a little overstated (not the actual weight of a head, just the requirement to be 10 lbs. positive to float comfortably). Even removing the "head weight", you would still be significantly negative.

I would not be comfortable jumping into the water that negative without ditch-able weight.

Best wishes.

For warm water don't go with both a steel backplate and a steel tank or you will end up overly negative and end up having to compensate with a big wing. If your wing fails then what? A much cleaner solution is to have an aluminum backplate or aluminum tank for warm water. A extra backplate is a pretty trivial expense compared to the cost of travel to a lot of warm water destinations.

I was using the steel tank as the worst case scenario. I assume I would probably be using an AL80 in both the warm and cold water dives. I was trying to see if one plate can meet both my cold and warm water needs. Using an AL80 my lift requirement comes down to around 20#s (Head 10, Tank 1.6, Regulator 2, Plate 6.5) so a 26# or 30# wing would suffice.

Do most people dive with AL plates in warm water?

Again thanks for the feedback for the novice.....

 

[TSandM]

A steel plate with an aluminum tank isn't bad -- the tank is -2 to begin with, and the plate is -5, so even if you have no exposure protection on at all, it takes only a very small wing to float you, and you should be able to swim up 7 pounds (at least I can, and I'm not terribly powerful).

A steel plate with large steel tanks is another kettle of fish, because there you can end up 15 or more pounds negative at the beginning of the dive, and holding that at the surface with a failed wing would be no fun at all.

The basic idea is to balance the things that float with the things that sink . . . if you want to dive large steel tanks in warm water, use an aluminum plate or wear a wetsuit.

 

[ams511]

Mike, you are buoyant so you float by yourself without help of the wing. This is especially true if you are wearing a 7 mil wetsuit. So the wing needs to float the rig alone. You also need to decide also where to carry the weight, either on a belt or on the rig. If on a belt the wing can be smaller as the rig is lighter. Wearing a 7 mil wetsuit you could dive with a steel plate and a steel tank and reduce the lead weight accordingly. The problem, as TSand M pointed out, is that a wing failure at the start of the dive will have trying to swim up at about 15 - 20 lbs between the tank, plate and regs. You should do a search for the term, "balanced rig" on here and online. You will find much info on weighting.

 

[Mike126]

TSandM and AMS511 - very good advice. I did chat via email with Tobin some more yesterday and he set me straight with a better understanding of what wing lift is all about. I think some of my earlier concerns were based on using a steel tank and SS BP in warm water with no wetsuit or a 2 mm shorty. As you guys also pointed out, that is just too much weight. His initial recommendation was the Torus 26 and long pattern SS BP (I'm 6'4"). After talking to him and reading everyone's feedback, I think I might go with the LCD 30 wing and SS long BP. While it may not be tuned as optimum as possible, the 4#s in terms of trim will probably not be noticed. But, for piece of mind the 4#s may help me sleep better.

The frustrating part is that when you read PADI's recommendations they say you should double your lift requirement. If that's the case I'd be using a 40# wing.

My weight will be carried on a belt and not the rig. It looks like for warm water dives I may only need a couple of pounds on a belt. Cold water with a 7mm I can cut back from 22#s to somewhere around 12-14#s. My goal to moving to a BPW was to remove the excess. Otherwise I would go back to the Zeagle Brigade.

 

[victorzamora]

Good for you, Mike. I think this is another case where Tobin's awesome service wins you a great setup.

 

[rhwestfall]

a word of "caution" as to the LCD 30. As much as I like mine, its also an aggravation that the hose elbow is in constant conflict with the first stage as it is centered on the top of the wing. Love my DSS gear, but dislike this.... The wing is great, especially for a tall diver as it is long and narrow. It will be a little "problematic" with short tanks like the HP80 (or AL63), and you have to be real careful of pinch flats.

 

[halocline]

Do most people dive with AL plates in warm water?

Again thanks for the feedback for the novice.....

It depends on the tank. With an AL tank, which is what most tropical charters/dive ops will provide, a steel plate is ideal as it offsets the buoyancy of the tank. For a steel tank, you don't want to be overweighted, so often an AL plate is better. It comes down your your personal ballast needs and to a certain extent wetsuit choice. Lots of people use 5 mil suits in warm water, and those can be pretty floaty.

---------- Post added September 27th, 2013 at 07:49 AM ----------

The frustrating part is that when you read PADI's recommendations they say you should double your lift requirement. If that's the case I'd be using a 40# wing.

Easy solution, take any gear recommendation by PADI with a grain of salt.