Building custom weight for BC

[plumcrazy]

Greetings, sort of thinking out loud right now. I am looking at my BC and am thinking that I could build a weight for it to eliminate a good portion of weight that I have to normally carry in the pockets. The BC in question is a "TUSA Imprex Pro cubic 3D". This particular BC has a somewhat independent harness and bladder. I'm thinking I could put a plate of stainless in between the back pad and the "tank holding cradle". I typically need 14 - 18 lbs of weight with my 7mm suit in fresh cold water which is where I anticipate the vast majority of my future diving to occur. I'm thinking that if I can fabricate a plate about 4" X 11" and maybe 3/8" thick it might weigh in at 8 -10 lbs. This weight would be right on my back and in between the shoulders. I don't know. wadda yall think, worth pursuing?

 

[deepseafalcon]

I don't see a reason why it shouldn't work, if there is a way to attach the plate to your backplate. Although I wouldn't be sure whether I wanted to lug around such a heavy BC.

What you could also do: try to remove padding (like said back pad). With the thick suit you are diving I don't think you really need it.

You might be surprized by the amont of weight you can leave on shore, that's at least what happened with my old BC (and again when I switched to a BP/W), and the one of my wife.
It might end up coming close to the weight of this plate you want to screw there.

 

[cool_hardware52]

Greetings, sort of thinking out loud right now. I am looking at my BC and am thinking that I could build a weight for it to eliminate a good portion of weight that I have to normally carry in the pockets. The BC in question is a "TUSA Imprex Pro cubic 3D". This particular BC has a somewhat independent harness and bladder. I'm thinking I could put a plate of stainless in between the back pad and the "tank holding cradle". I typically need 14 - 18 lbs of weight with my 7mm suit in fresh cold water which is where I anticipate the vast majority of my future diving to occur. I'm thinking that if I can fabricate a plate about 4" X 11" and maybe 3/8" thick it might weigh in at 8 -10 lbs. This weight would be right on my back and in between the shoulders. I don't know. wadda yall think, worth pursuing?

1) Be careful about mounting all of your ballast to your rig. Ditchable ballast has merit.

2) ((4" x 11" x .375") x 495 lbs / cuft)/1728 cuin/cuft = 4.72 lbs. lots of work and expense to get 1/2 way there.

Tobin

 

[fisheater]

Sounds like you're well on your way to re-inventing the BP/W.

 

[plumcrazy]

Sounds like you're well on your way to re-inventing the BP/W.

SHHHHHhhhhh.. Its a secret........

 

[plumcrazy]

I don't see a reason why it shouldn't work, if there is a way to attach the plate to your backplate. Although I wouldn't be sure whether I wanted to lug around such a heavy BC.

What you could also do: try to remove padding (like said back pad). With the thick suit you are diving I don't think you really need it.

You might be surprized by the amont of weight you can leave on shore, that's at least what happened with my old BC (and again when I switched to a BP/W), and the one of my wife.
It might end up coming close to the weight of this plate you want to screw there.

Thanks, this is going to prove to be more dificult than it sounds. The webbing, back plate, padding is really pretty well woven together. I'll keep looking though.

 

[plumcrazy]

1) Be careful about mounting all of your ballast to your rig. Ditchable ballast has merit.

2) ((4" x 11" x .375") x 495 lbs / cuft)/1728 cuin/cuft = 4.72 lbs. lots of work and expense to get 1/2 way there.

Tobin

1. Thanks, definitly want some ditchable ballast. I'm figuring I will still use the front weight pockets, more as trim pockets, 2-3 lbs each

2. GREAT FORMULA, Thanks I see that my as stated measurments need to be modified. Looks to me like hitting a number somewhere in the 6-8 lb area looks pretty doable.

Now I just need to find me some material. I figure if I can spend less than $100.00 doing this it's worth it.

 

[spectrum]

Remember that adding 4 pounds of SS does not remove 4 pounds of lead. The densities of the materials are different. It's the weight above that of the displaced water that matters.

Pete

 

[cool_hardware52]

Remember that adding 4 pounds of SS does not remove 4 pounds of lead. The densities of the materials are different. It's the weight above that of the displaced water that matters.

Pete

Pete,

This is a very common misconception. Lead (~720 lbs / cuft) is much denser than StainSteel (~495 lbs / cuft)

If one was to replace a volume of lead ballast with an equal volume of Stainless steel they would have much less effective ballast.

OTOH if one replaces XX mass of lead with an equal mass of Stainless steel there is much less difference in the effective ballast.

Lead "looses" about 9% of it's weight when submerged. (720-63)/720 = .91

Stainless Steel "looses" about 13% of it's weight when submerged (495-63)/495 =.87

The difference in terms of ballasting a scuba diver is trivial.

Of course 4 lbs of Stainless will be ~1.45 the volume of 4 lbs of lead.


Tobin

 

[spectrum]

Pete,

This is a very common misconception. Lead (~720 lbs / cuft) is much denser than StainSteel (~495 lbs / cuft)

Mo misconception Tobin. Perhaps a misrepresentation of magnitude but no misconception.