BP/W for me and my son?

[beaverdivers]

The choice of plate material is a function of required ballast. And you have provided zero information in your question about how much total ballast a specific diver might require.

OK,

84 degree water, skinny ( very neg. buoyant diver ) w/non- buoyant suit = zero weight needed

What would be the proper BP/W?

In general:

Wings get bigger as you move further from the equator, the water gets colder and suit buoyancy typically increases

Would a small tropical wing work up North?

 

[rivers]

What would be the proper BP/W?Would a small tropical wing work up North?

No, just as a travel jacket BC wouldn't be appropriate for cold water diving.

 

[Storker]

Wings get bigger as you move further from the equator, the water gets colder and suit buoyancy typically increases

Would a small tropical wing work up North?

The LDS that probably sells the most BP/Ws in all of Norway (at least, they are the ones who push BP/Ws hardest), usually recommends a 40# wing for single tank diving in Nordic waters. If I've done my math right, my rig - weighted for winter diving - would at best be borderline buoyant with a 30# wing, so I followed their advice and have a 40# wing on my BP.

 

[cool_hardware52]

OK,

84 degree water, skinny ( very neg. buoyant diver ) w/non- buoyant suit = zero weight needed

What would be the proper BP/W?Would a small tropical wing work up North?

You *still* haven't told me what cylinders the dive is using.

Ballast is *everything* the diver gets into the water with that does not float.

Wings must be sized for the most buoyant suit they will be used with. Doesn't matter if the diver only dives cold water once a decade.

Will the smallest possible warm water wing work in cold water? Typically no. OTOH if the cold water application is well understood, i.e. I provided with *all* the info I need, and we know the actual buoyancy of the divers cold water suit then it's common to size a cold water wing that is still practical for warm water, a little bigger but not a 98lbs, dual bladder monster.

Tobin

 

[beaverdivers]

You *still* haven't told me what cylinders the dive is using.

Let's say a standard AL80. The neg. buoyant diver still sinks w/ 500 psi w/ no weight. What BP & which wing would you recommend? They are only going to dive in warm water w/ a non- buoyant suit.

Wings must be sized for the most buoyant suit they will be used with. Doesn't matter if the diver only dives cold water once a decade.

Wow! If they are diving a 7mm (needing 16 lbs. to be neutral at 500 psi w/ a steel tank )only once up North, how big of a wing would they use even in the tropics?

Will the smallest possible warm water wing work in cold water? Typically no.

Makes sense.

it's common to size a cold water wing that is still practical for warm water, a little bigger but not a 98lbs, dual bladder monster.

Like a 60 lb wing

 

[decompression]

BD, if a neg bouyant diver with 500 psi and an Al80, I'd put him in a AL plate with an 18# wing and tell him to inhale.

It's unbelievably rare to have someone more than a pound or two neg, bare a$$ in fresh water. So, In which case the lung capacity will more than compensate no to mention the added buoyancy of seawater.

Still not a hazard.

This is how we start every class......
UTD EXTREME SCUBA MAKEOVER - YouTube


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[cool_hardware52]

Let's say a standard AL80. The neg. buoyant diver still sinks w/ 500 psi w/ no weight. What BP & which wing would you recommend?

If you want a recommendation please provide, in a coherent fashion, the following:

Divers height and weight
Exposure suit used and the buoyancy of that suit
Cylinders to be used.

Try to focus. What I need to recommend a wing is the buoyancy of the diver's suit, not how much lead it takes to get them neutral.

Buoyancy compensators are used to compensate for things that change wrt to depth and that's pretty much only the suit.

Personal buoyancy for scuba divers remains constant wrt to depth. Personal buoyancy will impact total weighting (and maybe tank choice and plate choice) but it does not need to be compensated for as it does not change wrt to depth.

Like a 60 lb wing

Shudder.........

Tobin

 

[beaverdivers]

Divers height and weight

5'6" & 109 lbs

Exposure suit used and the buoyancy of that suit

non -neoprene suit & it has zero buoyancy

Cylinders to be used.

80 AL

 

[bryanmc57]

Casey... Do you have any relatives named Stuart? J/K LOL

 

[fjpatrum]

OK,

84 degree water, skinny ( very neg. buoyant diver ) w/non- buoyant suit = zero weight needed

What would be the proper BP/W?Would a small tropical wing work up North?

In my case it's a steel plate (~6 pounds) with stays (~1 pound) and anything from 0 pounds with a 3mm wetsuit to 4 pounds with a 5mm wetsuit. So, without buoyant suit I'm 2.5-3 pounds heavy? That's not going to cause "buoyancy problems" that are even remotely close to dangerous in anyone but the greenest of newbs.

Again, I'm 6'1, 170 pounds, 3-5% body fat, negatively buoyant (I "float" with the surface just above my eyes) without a wetsuit. I use the same ~18# wing in 40 F water with my dry suit as I do in tropical 80+F waters. I have dived the same plate and wing with everything from a 1mm short sleeve top (essentially non-buoyant and I was cold) to 14+mm of neoprene (not recommended) as well as my dry suit with mid weight thermals underneath.

With AL80s on most of these dives I have never been "over weighted" except when I found a weight belt on a quarry dive. With my HP 100s and non-bouyant suit I would be ~8 pounds heavy at the end of the dive, which could be more of a problem but still well within the "swim it up" realm for me.

You can have all the same weighting issues with a BP/W as you can with a vest and vice versa. Proper weighting isn't about gear, it's about attention to detail, no matter what kit you have.