Question Trim position in a BPW?

[Still Kicking]

I have. I do need to find one. But ideally if I go steel I’ll need to get wing with more lift.

No ... you will have the same weight as now (assuming you're correctly weighted) but in a different place. See my comment above about center of gravity.

Also, you can try moving your tank. Move the backplate down the tank a few inches so you place the weight of the tank/valve/reg nearer your head.

 

[MB NZ]

More weight at the top, less at the lower end. That's all you can do. As someone else said , it's a matter of physics. Imagine yourself as a seesaw with the centre of your body being the pivot. Moving the cam bands down the tank if you have space could help. Short of dangling ankle weights around your neck, a change of kit maybe required.

 

[rongoodman]

Is your body flat from shoulders to knees, no matter your attitude in the water, or are you dropping your knees? Posture does play a role, and you need to be maintaining a little tension in your glutes in order to maintain it. I agree about switching to a steel plate.

You say the issue is worse when changing direction, which makes me wonder how you’re doing it. Helicopter turn or something else?

 

[Eric Sedletzky]

I have. I do need to find one. But ideally if I go steel I’ll need to get wing with more lift.

The only reason you would possible need a wing with more lift is if you decided to attach a load of non ditchable weight to your rig and/or if you went to a 6 lb steel plate and a bigger steel tank.
If your weighting is dialed in now then your OVERALL weighting isn’t going to change.You’ll just be taking some off the belt and adding it back onto your rig higher up where you need it to trim out.

 

[rx7diver]

Another way of getting weight higher is to wear two 1st stages (two complete regulators). I dive an old-school Y-valve on my rig I wear for moderately deep solo dives. (LP cylinder.) Love it! I prefer it vs. an H-valve, but an H-valve will work, too, though probably not as well.

Or wear a single Scubapro Mk7!!

rx7diver

 

[Nemrod]

I’ve been diving a BPW for the last year, I like to say the least but I’ve been noticing I’m still in “seahorse pose” in the water sometimes - especially when I’m changing direction. A dive buddy pointed that out to me recently. Else, I can get into a mostly trim position in the water with my arms crossed(hands near my hips) or in “tech diver” pose.

There’s 5-6lb of trim weight on my upper cam band and depending on the tanks I dive, there’s 14-20lbs of lead on a weight belt. How else can I configure my weight? I think I trim out better in HP100s, which I now own one - it’s at the LDS for an hydro and VIP.

My current setup - 7mm wetsuit, layered with a 7/5mm hooded vest for exposure. LP95 tanks for air, Tusa T-Wing BPW with an dogbone aluminum backplate. 27lbs of lift.

You have too much weight and too much of that weight is too low on your body. You may also consider less negative fins and as suggested a steel plate and possibly moving your tank higher. Also, stop flutter kicking, bend your knees up more and use a bent knee frog/flutter or sculling. If you have negative fins (and legs as many men and women do) and they are fully extended then you are going to rotate feet down when static. A steel plate will not require a larger wing, all else remaining the same.

 

[inquis]

Seahorse trim can be caused by being leg heavy, but it can also be a defensive measure when you're are head heavy. The only way to be sure is to put yourself horizontal, stop kicking/skulling/moving, and see which way you rotate. A buddy's guidance is helpful to tell you if you are actually horizontal.

After that, you need to move weight to prevent the rotation when horizontal & motionless. (If legs drop, move weight toward your head, or vice versa.) You can keep your current wing, since you're not adding more weight.

 

[Kupu]

Another thought would be to remove the padding from the Tusa T-wing backplate, which should allow 1 lb less lead needed on the weight belt.

 

[landphil]

Steel plate is the secret sauce for bpw single tank cold water diving. It spreads a good chunk of your weight right over the floatiest part of your body (your lungs.) I’m super leg heavy and dive my 9mm wetsuit with a 10lb plate and 2.5 lbs in each waist pocket. Dry suit diving I’ll add another 12 lbs to the top of my tank (cause still leg heavy and my suit doesn’t hold much air in the legs.) It’s all on lace-through weights on a tank band that I just clamp down above the top band.

You can do the calculation to figure out what size wing you need. A great starting point is being able to float your rig when it’s not attached to you; so, just add your full tank buoyancy to your backplate and lead weight to see if you make it. But I would recommend 30+ for a dedicated cold water rig- I run a 37; since I like to keep all of my weight on the BC But a lot of weight belt divers do fine with 26-30lbs of lift

 

[jellycatsdad]

Ok, so next dive what I’ll do is get my tank higher - but not so high that I bang my head against the valve/first stage. And I’ll give the 4lbs of weight on the valve a try.

Eventually, I’ll buy another BPW, this time something with a steel plate and 35-40lb wing to deal with future drysuit diving. I can swap out the plate for steel if I wanted to as well.

Another observation I made - in the pool wearing just a dive skin or baggies and using an Al80, I needed 5lbs of lead in a cam band pocket. With the LP95, I needed 4lbs.