Where Did I Go Wrong?

[Mike Boswell]

Put the lead in a weight belt. It will solve your problem.

This is a great example of what Tobin often says . . . rated lift on a wing may not be what you actually get with a tank attached to it.

I agree a weight belt is a viable workaround, but I don't like weight belts and my goal is to reduce gear, drag, and complexity.

My actual problem seems to be that my 30-pound wing apparently has less than 28 pounds of lift. This could be caused by several things, including a bunched-up wing membrane, a flatter-than-usual backplate, or a weak dump valve spring. One possible solution could be to shim out the tank by a quarter of an inch or so, which might allow the wing to more fully inflate.

 

[Mike Boswell]

I have an older Oxycheq Signature 30# wing on a Freedom Plate. With an extra 5 lbs of lead attached to the plate and an HP100 or HP130, plus a canister light, unless I hit the inflator until the OPV cuts loose my rig sinks.

Point being, are you filling the wing until it comes out of the over pressure valve? If not try it. What you describe should not be that negative.

I will agree with TSandM that you should probably be carrying much of the weight on a weight belt.

Yes, I am filling the wing until the OPV burps, and the rig still sinks.

 

[Rainer]

A 4# weightbelt is really pretty easy to manage...

I agree a weight belt is a viable workaround, but I don't like weight belts and my goal is to reduce gear, drag, and complexity.

My actual problem seems to be that my 30-pound wing apparently has less than 28 pounds of lift. This could be caused by several things, including a bunched-up wing membrane, a flatter-than-usual backplate, or a weak dump valve spring. One possible solution could be to shim out the tank by a quarter of an inch or so, which might allow the wing to more fully inflate.

 

[Eric Sedletzky]

I agree that the wing is constricted by the tank, but since that is the way the wing is supposed to be used, one would think this constriction is taken into account when rating the wing. Tobin at DSS says he takes it into account, but I don't know if Oxycheq takes it into account.

My tank is the XS Scuba HP100, and according to them it is -10 lbs full with the valve. (see XS Scuba Worthington Steel Cylinder Specifications)

Tobin has one of the flattest plates out there. Oxycheq's plate might have more bend in it. If the plate is too flat and you're not using a STA there isn't a lot of room for the wing to fully inflate with that tight of a wedge between the tank and plate, and I know the Mach V is very narrow. Maybe Oxycheq gave it that rating with their plate which might have a wider wedge.

Like DA Aquamaster said, maybe you could stand to lose a few pounds off your configuration and move a few remaining pounds to a weightbelt.

And if you got a DSS plate why didn't you just get a DSS wing to go with it?

 

[Mike Boswell]

Tobin has one of the flattest plates out there. Oxycheq's plate might have more bend in it. If the plate is too flat and you're not using a STA there isn't a lot of room for the wing to fully inflate with that tight of a wedge between the tank and plate, and I know the Mach V is very narrow. Maybe Oxycheq gave it that rating with their plate which might have a wider wedge.

Like DA Aquamaster said, maybe you could stand to lose a few pounds off your configuration and move a few remaining pounds to a weightbelt.

And if you got a DSS plate why didn't you just get a DSS wing to go with it?

You may be right about the plate flatness. I could bend it a little more and see. As to the wing, it's a long story...

 

[timle]

Also, the part of the wing that happens to be above the water isn't doing you any good, buoyancy wise.

I would assume if the rig is sinking the wing eventually gets fully submerged.

 

[Eric Sedletzky]

You may be right about the plate flatness. I could bend it a little more and see. As to the wing, it's a long story...

Or you could get a STA and that would give the wing a little more room to inflate. That is if you don't mind the tank sitting a little further away from your back.

 

[Mike Boswell]

Peter you have an older Oxy wing which is a little wider and bigger than the Mach V. I'm figuring he has a M5 because that's all you can get now. And also the freedom plate is cut away so that allows the wing to inflate more.

But yeah I agree, more weight needs to be put on a weight belt.

Lots of folks are advising a weight belt - but I don't really understand the advantages of a separate weight belt. Can somebody enlighten me?

BTW, I can easily ditch the weight in one or both of my velcro-flapped waist belt pockets.

 

[Rainer]

LOL, it's simple, it'd make your rig float again.

Lots of folks are advising a weight belt - but I don't really understand the advantages of a separate weight belt. Can somebody enlighten me?

BTW, I can easily ditch the weight in one or both of my velcro-flapped waist belt pockets.

 

[Mike Boswell]

LOL, it's simple, it'd make your rig float again.

CRTM (Chuckling Ruefully To Myself) - Yeah, that is true, and I knew that...

I can also get my rig buoyant by using a little air, as it is only about a pound or two negative with the full tank.

But ... there seems to be a consensus here that the weight should be on the diver, not on the rig. I would like to know the reasoning behind this.

The only reason I can think of is that if you take your rig off underwater you would like to still be neutral instead of very buoyant. This might apply most critically with thick wetsuits, drysuits, wrecks, caverns and caves.

BTW - I just finished the rescue class and I discovered that a floaty rig is a good thing when you are trying to do rescues, because you might want to ditch the rigs in order to quickly swim a victim to safety.