I'm a newbie who tried a BP/W for the first time today...

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Wow, you must be 0% body fat and be solid muscle.

On top of densonium endoskeleton with adamantium grafts. Even if you allow for 10lbs tank, 6 lbs plate, and another 10lbs of solid cast lead STA, you'd still need steel knees and hips, and very tiny lungs, to sink a fully inflated 30 lb wing.
 
View attachment 522555
Even the pure harness has unneeded padding that creates positive buoyancy.

At least to me, this qualities as bp/w with basic harness. Scubapro backplate and pad are made to the same spec or even made by Halcyon. The pad is very thin, not those thick foam pad. Material is like the wing shell. I don't see how it can contribute to positive buoyancy. But I don't use one myself.
 
I never said I fully sunk it though.
 
I never said I fully sunk it though.

Still.. with no wetsuit and a single steel tank you still should have been bobbing like a cork with a 30# wing fully inflated. I sometimes dive with an 18# wing in that config which can be a little marginal at the beginning of a dive, but the 30# should have been heaps. Like you i'm a "sinker", i cannot float normally without constantly treading water.

As many people have said before me, something is amiss.
 
I'm also a sinker. With a drysuit, 27# wing, six pound backplate, 23 pounds on a weightbelt and a steel 130 I float just fine at the surface.
 
There are going to be a few factors that will influence the lift you need for your wing.

Your height and weight, the areas where you dive, (cold water or tropical ) hence your exposure suit thickness, how much additional weight you need, max depth of dive, and if the weight is integrated into your harness (if so you should have enough lift to float your rig on the surface).

If you're optimally weighted, you should be able to hold a safety stop at 5 m with 50 BAR left in your tank and your wing is empty or barely filled with any gas. (sorry I don't do psi and imperial).

So with all of the above in mind, I suggest you get fully kitted up and do what would be a typical dive for you in your environment. When you reach your safety stop hang for a few minutes and for this exercise have 30-50 bar left in your cylinder. Empty your wing completely and see... do you float up or sink? Ideally you should be neutrally buoyant. Once you've dialed that in you will be able to know how much weight you really need... and at your maximum depth, your wing should then compensate for any exposure suit compression. In addition as mention before, the wing should be able to float your entire rig on the surface.

Generally if you're weighted properly, you will probably find 30lbs of lift to be sufficient, however, I will say that the difference between a 30lbs wing and a 40lbs wing in terns of actual size and how much additional drag is added with the larger wing is quite minimal - especially with today's designs like Oxycheq, Halcyon, etc.. they make nicely streamlined smaller overall designs that do not induce too much drag.
 
So I sent the shop an email just to ask about it, and she again verified that it was fully functional and nothing was wrong with the wing and that there were no weights in it.

Her guess is that I am both just a sinker in general, but also that there was a chance that the crotch strap wasn't tight enough and that at the surface, the wing floated a bit up, making it so I wasn't quite on the surface as I should be. When we fitted the harness on me we mainly did it on my back and shoulder area, and didn't make adjustments to the crotch strap. It felt okay on first glance, but now that I think about it, I did have my trunks on without a wetsuit, so it may have been dangling down a bit so that it wasn't just riding up my shorts. So that could explain the feeling of me "sinking" a bit at the surface.

She also was just thinking that I may prefer an aluminum plate just based on my build and her experience with people of my size. She didn't recommend a 40lb wing at all though and said in her 8 years of diving with people using BP/W, only 1 person has ever needed one and he was a really big guy.

I will say though, I was really surprised how much I sank in the water with no air in the BCD. Like if I was in the open ocean and sinking that fast, it would kind of freak me out because I don't know if I could clear my ears fast enough, like without knowing it was coming.

She suggests I start with a steel plate though and do salt water dives to see how it performs there as well with wearing a wetsuit, and that if I get it from her, and the steel plate doesn't workout for me and it's too heavy, that I could just swap for the aluminum plate.

So speaking of that, I know you guys suggested the DGX brand (as others have) for the BP/W. The only brand this one shop sells is ScubaPro and it is clearly more expensive. Is the brand being SP pretty much what you are paying the extra money for? Is the quality of the DGX stuff and SP stuff comparable or is one better than the other? I haven't priced out at all how much the SP setup would be if I buy it from the shop yet so I don't really know the full price of everything if I went that route.

Again, this was just the X-Tek wing with a very minimal harness, basically what the DGX setup shows in the link someone provided. It was a wing, a backplate, and a harness with no padding or extra on it.
 
There are going to be a few factors that will influence the lift you need for your wing.

Your height and weight, the areas where you dive, (cold water or tropical ) hence your exposure suit thickness, how much additional weight you need, max depth of dive, and if the weight is integrated into your harness (if so you should have enough lift to float your rig on the surface).

If you're optimally weighted, you should be able to hold a safety stop at 5 m with 50 BAR left in your tank and your wing is empty or barely filled with any gas. (sorry I don't do psi and imperial).

So with all of the above in mind, I suggest you get fully kitted up and do what would be a typical dive for you in your environment. When you reach your safety stop hang for a few minutes and for this exercise have 30-50 bar left in your cylinder. Empty your wing completely and see... do you float up or sink? Ideally you should be neutrally buoyant. Once you've dialed that in you will be able to know how much weight you really need... and at your maximum depth, your wing should then compensate for any exposure suit compression. In addition as mention before, the wing should be able to float your entire rig on the surface.

Generally if you're weighted properly, you will probably find 30lbs of lift to be sufficient, however, I will say that the difference between a 30lbs wing and a 40lbs wing in terns of actual size and how much additional drag is added with the larger wing is quite minimal - especially with today's designs like Oxycheq, Halcyon, etc.. they make nicely streamlined smaller overall designs that do not induce too much drag.
Thanks for this. With my recent previous dives with jacket style BCD, I've had 6lbs of weight (3 on each side, once with integrated weights, once with belt) and I was basically neutrally buoyant with no air in my BCD for most of my dive. Every now and then I'd give one quick squeeze maybe. These were dives around 30-40ft.

So that is why I was shocked at how much I just sank with the BP/W on with no weights at all. But then I have to think about now having wetsuit on, being in freshwater, and also having less buoyancy due to no big bulk jacket BCD.
 
https://www.shearwater.com/products/swift/

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