BP/W: I officially don't get it

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Dumpy claims that BP&W's essentially **Have** to force the diver forward at the surface, i.e. one diver based on his personal experience, knows for a fact that BP&W's are suboptimal at the surface, and this cannot be corrected with setup or proper weighting.


......

OTOH if the diver is properly weighted they need only a small "puff" of gas in the wing. This gas will be behind the divers head and shoulders only and as such cannot push the diver forward.

Weight distribution can help, but correct total weighting and proper harness adjustment, particularly the crotch strap are important.

I know that I can make a diver miserable in a BP&W with a loose crotch strap and too much weight, and in 5 minutes I can make them happy campers with a harness adjustment and proper weight check.

The choice is yours who to believe.

Tobin


I do not intend to get in a pissing match, but yes if you put a small amount of air in the wing AND you lean back, then you can float on the surface without too much trouble. However, in rough seas, when you want to relax and be seen by a boat (and to have your head held out of the water to the maximum extent practical) a BC often works better, is more relaxing and comfortable than a BP/W in my opinion.

Why would anyone want to beleive YOU about what makes ME more comfortable at the surface? I've been diving actively for around 35 years.
 
If you are pushed face down, and carry very little or no weights, and the weights are correctly positioned, there is only one way to fix that. put on more thermal protection, and add some weights to counter the extra buoyancy.
 
If you are pushed face down, and carry very little or no weights, and the weights are correctly positioned, there is only one way to fix that. put on more thermal protection, and add some weights to counter the extra buoyancy.

Humm, well no not really.

Different selection of components, lightweight plates vs SS plates, buoyant cylinders vs negative cylinders etc. can solve basic overweighting problems.

If the diver is correctly weighted, i.e. total weighting, and is using a crotch strap very little gas is necessary in the wing for comfort at the surface.

If there's only a puff of gas in the wing it cannot force the diver forward.

Tobin
 
You know, I listen to these arguments with complete confusion. I have dived a bunch of different backplate setups in different water conditions: Double steels in salt and fresh water, double aluminums in fresh water, single steels in salt and fresh water, drysuit dives and wetsuit dives, temperatures from 43 to 81 degrees. I've never been pushed forward in the water. I like my head well out of the water when I am on the surface, so my wing is usually filled pretty full (often until the OPV pops) and I STILL don't get pushed forward. In cold water, I use a heavy weight belt (16 to 20 lbs) with the weight mostly off to my sides, over my hips, and with a single tank, I use 6 lbs on the cambands as well (steel plate). If anything, the gear seems to want me to float on my back (especially in the doubles) and I may have to work a little bit to stay upright.

I think you have to have the crotch strap pretty loose to get pushed forward.
 
What I've found is that I can position myself vertically, face-up, or face-down in a BP/W at the surface, with about equal ease. As far as I know, BCs aren't designed to function like type I life preservers.

If you're doing seriously cold water diving it's probable that you'll actually have a lot of other weight, and wherever that's positioned it'll be forwards of the buoyancy bag.

Anything I've missed?
One thing comes to mind... if you're doing cold water diving, you're also almost certain to have a crapload of forward buoyancy from your exposure protection, which should about offset the downward force from your weights.
 
I do not have thousands of dives under my belt, but what I do have is a properly set-up BP/W. I went limp on the surface this weekend just to see what would happen, and I just bobbed there like a cork, more or less neutral. If I leaned back, I would plop onto my back. If I leaned forward, I would plop face down. There was no inherent bias either way, and that's pretty much ideal for me.

I've also had a few experiences with improperly set-up BP/Ws (sometimes, just a bit off), and when you screw things up (improper shoulder or crotch strap lengths, significant overweighting, etc.) you can definitely feel yourself being pushed face-down, especially if the bladder is quite full. However, this was always immediately eliminated once the rig was set up correctly.

I've not noticed much difference with a jacket BC (someone has already mentioned that BCs of any type are typically not PFDs), but the one advantage they may have at the surface is that the entire bladder is under your armpits below the surface, providing you with maximum lift for the bladder capacity. Once comfortable with the "ride height" of a backmount-type BC, this wasn't an issue for me in chop, swells, etc.
 
So what do I have wrong with my doubles set up that I am not comfortable on the surface?

I am perfectly comfy with my singles BP/W whether I dive HP130, LP85 or Al80 with SS or Al plate, and whatever weights I need (varies from tank and undies between ~3-16lbs). However, when I move onto dubs it is NOT comfortable to bob around for any prolonged period. Any chop and I certainly keep reg in mouth because I float very low (putting more air in wing makes me more tipsy).

My dubs are LP85s, plate is Al, I have 3 lbs tailweight for balance and with very heavy undies I add 4-5lbs on waist. No other weird ballast. I like to cinch my crotch strap tight because my harness is bit looser (have some back bending issues, so like to make donning easy), harness is not ridiculously loose though.

I feel more balanced when I add weight - maybe more weight lower on the body would actually make the floating more comfy? SS plate with doubles was way too much weight high up. I find it hard to push onto my back with the doubles, it's not comfortable to stay in that position if there is much air in the cell. If there isn't much air, I need to crane neck and I'll get slurpies down the seal. The wing is Oxy Vertex btw, donut.

I am BP/W proponent but I'd welcome some more surface comfort with the doubles unit. I am quite sure I do not have any extra weight on me, and I have tried the different holes both on plate and wing multiple times. Still I end up having to do a bit of leg work when on surface.


.... maybe I just have fat legs that want to run from under me.... no rig will fix that...
 
What are you wearing for exposure protection? Heavy neoprene might make your legs floaty.

And what lift wing are you using? It almost sounds as though you might not have enough lift for the gear you're carrying.

I dive double 85s at home, but I have to admit I carry a LOT more weight than you do. I use an Al plate, 6 lb v-weight (don't ask), and 16 pound weight belt. I think the belt helps me balance at the surface, to some degree.
 
I purposely inflate my wings to maximum expansion (the overpressure valve was popping) and my BPW simply doesn't put me face down in the water.
 
I have been watching this thread for a wile this is my two cents .


I have been diving both jacket bc's with weight belts and intergraded weights both regular jackets and back inflates .All i can really say is they suck i have to say they never fit rite there either too small or to big . the weight pockets are never big enoph for cold water diving so your always forced to were a weight belt that drags your fins down for bad position in the water. And once you go tech jacket bc's are just horrible (other than the diverite trans pack ).

I have close to a 1000 dives in all conditions .950 of those are in bp/w or in a transpack (nomad sidemount rig ) . simple streamlined no useless dohickies . In all that time i have never seen somebody being pushed face down using a plate and wing combo unless hugely over weight or the rig is poorly adjusted ( but my scubapro night hawk that i started with did this to me all the time) .

So if somebody really thinks that a jacket bc is superior to a bp/w in anyway maybe. should maybe pick up a book and learn to set up the plate properly or should pic up another sport like golf .


BTW pick up the book dressed for success by Dan mackay. There is a hole section on how to fit a backplate
Its sold at Welcome | Global Underwater Explorers
 

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