BP/W HP100 vs AL80 weighting

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A very basic question for anybody--I searched a bit but didn't see an answer.

How on earth do I know the buoyancy of my BP/W? Is the weight close enough? (I do have some padding, but it's supposed to be neutral.)
 
I'll add my input here which may or may not muddy the waters.

My Summer rig is 15L faber steels (HP120?) on a Dive Rite Transpack harness and voyager 36# wing and a 3mm suit. There is no plate. It does had a back pad that they claim is neutral but which I figure is worth +2. For this rig I carry zero weight, I'm a bit over perhaps +4.

One nice thing is that the wing is big enough that even if I roll in without adding air, it will still support me at the surface (not much but enough to stop a neg entry or if I had an emergency enough to allow me to get out of the rig)

If I move to an AL 80 then I remove the back pad, and add +2-4lbs of lead (And can dive with just +2 but like the additional head room that +4 gives on a safety stop)

I have in my storage 2 harnesses with AL and SS plates, which I moved away from because they were adding too much weight, Although this year I'll be dusting off the SS plate and harness for my DS because I didn't like the placement of the lead last year (+12lbs) So this year I'll just have to add +6 in addition to the plate

I can't say I've ever used the wing calculator, and maybe my wing is too big (although it works with my big tanks) I've used a 30# wing and didn't get on with is as at the surface it didn't feel as though it had enough lift. That might be explained by the wing not being adjusted properly (too high) or just something in my head - never the less I'm happy at the surface in chop in my current set up.

My wing sizing has always been by gut feel, and weighting by feeling how much air I have in at the Safety stop (reaching around and squeezing my wing whilst slightly head down)
 
I've been playing with this calculator for a couple weeks now and no matter what I do with it, I can't get it show neutral at the SS with a steel tank with just a skin. Even if you drop the 2 lbs of trim weight that you are including, it's still -12 and -4. The only way I can get it to balance, with a steel tank, is to wear at least +7 lbs exposure. Let me know if you figure it out, ha!

@seeker242 I just thought of another way we can make this combo work..starting eating a lot of these!

homemade-twinkies.jpg


Seriously, though, after talking to Tobin I realize how simple this really is. If the diver is neutral, nothing to add or subtract. Everything else but the suit are negatives if diving steel. So if my 2/3 is +5 in the water I will be just a tad overweighted. Still going to test it's buoyancy, and really curious how buoyant my jacket is...guessing at least 4lbs!
 
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As a rule of thumb, add 2 lbs per millimeter to offset the wetsuit. From there you can fine tune according to your own body.

I have read somewhere that each mil of weight suits = approximately 2 lbs. So your guess of +5 kind of fits that.
Search for that rule of thumb and found by Quero right here in 2013 see above.
 
https://www.shearwater.com/products/perdix-ai/

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