Backplate and Wing - Weights

[Taath]

I have no idea how much (absolute) lead you need in fresh or saltwater, but the difference in the weighting requirements is pretty exact, since sea water has a specific gravity of very close to 1.025 (when the salinity is around 3.5%).

Fair enough. I'll definitely have to try that out once I get my weighting figured out with the BP/W.

I dive a SS BP/W with a HP100 in local San Diego waters. I have a trilam DS and weigh about 200 lbs. I'm new to DS diving but am wearing 8lbs steel dss plates attached to plate and 12lbs. On a weight belt. Total weight with plate is 26lbs. I feel properly weighted at 500 psi during safety stop. You would most likely need 6 additional lbs with al80. I use a soft belt with pouches for soft weights. Its comfortable, I don't notice it. I would only dive steel in ocean with DS. Just my two cents...

Thanks ScubaSteve. Wearing the belt a little bit lower so it doesn't overlap so much with the waist strap from the harness?

 

[diversteve]

There's also weight harnesses - most have droppable weight options. google this: scuba weight harness

 

[Taath]

A little off topic, but not entirely........do you guys think it would be feasible to dive a pair of LP50s with a manifold using a 30lb lift single tank wing?

 

[Aqua-Andy]

A little off topic, but not entirely........do you guys think it would be feasible to dive a pair of LP50s with a manifold using a 30lb lift single tank wing?

I guess it would all depend on the wing, manifold and bands. I have used my HOG 32LB wing with a pair of LP50's and had no problem. The tanks I was using had a narrow manifold and bands so that may have made a difference, the wing could inflate fully without being restricted between the plate and the wing. I will say it was a dream rig to dive, the tanks sit very close to your back.

 

[Taath]

I guess it would all depend on the wing, manifold and bands. I have used my HOG 32LB wing with a pair of LP50's and had no problem. The tanks I was using had a narrow manifold and bands so that may have made a difference, the wing could inflate fully without being restricted between the plate and the wing. I will say it was a dream rig to dive, the tanks sit very close to your back.

Fair enough. That's exactly what I'm trying to accomplish with that. A minimal, streamlined rig with redundancy built in. The bands and manifold I'm looking at are 8.5" to 8.5" center to center. Going to be using a Deep 6 wing and plate. I'll have to do some measuring and fiddling around once it arrives.

 

[tbone1004]

A little off topic, but not entirely........do you guys think it would be feasible to dive a pair of LP50s with a manifold using a 30lb lift single tank wing?

depends on the wing. Halcyon Eclipse? Probably, DSS LCD30? highly unlikely. It has more than enough lift in theory, but most of that is not available due to the tanks. You also run the risk of bending the plate if you use the power inflator.

 

[halocline]

One of the older dive rite travel or venture wings might work, they're pretty wide. Shouldn't be that hard to find.

 

[eelnoraa]

Putting all ballast on your rig doesn't sound all that balanced. How big is your wing? With 20lb ballast, 6lb plate, 1.5lb STA, you are at 27.5lb negative total. With AL80 full (-2lb), you are at 29.5lb negative. Add misc stuff, with a 30lb wing, you rig will sink without you in it. Youself will be about 23lb positive, if you need to ditck your rig underwater, you will also shoot to the surface. I would suggest putting 10-12lb on a belt. It is still very easy to manage.

 

[eelnoraa]

A little off topic, but not entirely........do you guys think it would be feasible to dive a pair of LP50s with a manifold using a 30lb lift single tank wing?

I think 30lb will be very marginal with your number. If you need 27.5lb with AL80, that means your suit is about 23.5lb positive. Double LP50 has 100cf of gas. That is 8lb. A wing should compensate thing that change in buoyancy. If you have a fully flooded suit at the beginning of the dive (full tank), you will be -31.5lb. A 30lb wing will not be big enough. It has nothing to do with double LP50's band or manifild. Even with HP100, 30lb will still be marginal with your number.

If you determine your suit isn't as positive, then a 30lb wing may work.

 

[Derelict]

In all honesty, if he is at the point of ditching his rig, he has bigger issues than his weighting distribution.