DUMB (MAYBE) BP & WING QUESTIONS

[oversea]

I am currently working to set up a new bc. I was certified about two years ago. I currently use a sp classic plus, al 80, twin jets etc. I would like to dive some wrecks out in the ocean this summer and am planning some equipment changes. As opposed to diving doubles, I have decided to go with steel 120's and a 30 to 45 cu ft pony for redundency. While the classic plus has suited my needs, I really don't like it. It feels large, and does not allow me to position my gear quite as I want it. I like the air2 (as I know many don't) because it keeps things smaller. My main problem is my physical body weight increases and decreases, so some times its a bit big, other times it's right. My ultimate choice is a bp and wings. I seem to like the Hammerhead bp but have a few general questions. I searched some threads for this but I may have missed the answer.
1. what options for weighting do I have? I really don't like a weight belt.
2. How is the tank attached with an STA? does the tank bolt to the STA with stanless bands or is their strapping and clasp?
3. For colder waters (northeast) I assume a stainless backplate (for the weight) is better?
4. What is a proper way of determining the size of the wing?
Thanks for any info

 

[salty]

I started with almost an identical set up as you, as I did more wreck diving I also changed my gear.

1. A 6 pound plat plus a STA with about 6 pounds should be most of your required weight. A belt with a small amount of additional weight will hardly be noticed. Are you diving dry or wet?

2. The tank is straped to the STA with normal cam bands. The STA bolts to the plate.

3. Usaly

4. The wing needs to support you at the beginning of the dive with all your weight and full tanks. There are a few good threads going into this process hear and in the DIR/tech/Hog forums.

 

[oversea]

when you say cam bands, your are referring to the type on my classic plus?

 

[cool_hardware52]

Oversea,

If you can remove the cambands from your current bc, you likely can use them in a STA.

You may find a weight belt handy for adjusting trim. Some find having all their weight on the plate is great, others find having a belt with a few pounds helps trim them out. This will vary depending on the tank you use.

My plate weighs ~11 lbs., and I typically wear a 8-12 lbs belt depending on the tank I'm using. I like having some weight on the belt especially if I don the gear in the water. I wear my belt under the harness, so I have it on when I enter the water. With no weight on the belt your kinda pinned on the surface.

Wings or BC's or Buoyancy Compensators, are required to "compensate" for the buoyancy your exposure suit looses as you descend. As long as your weighted "neutral" at the surface with no air in your wing, the max buoyancy you can loose is the lift your suit provides. How much lead does it take to sink just your wetsuit, i.e. without you in it?

Same holds true for dry suits. How much lead does it take to sink just you in your DS without any other gear, at the surface? Even if you flood the suit it won't loose more than this amount.


Regards,



Tobin

 

[oversea]

Oversea,

If you can remove the cambands from your current bc, you likely can use them in a STA.

You may find a weight belt handy for adjusting trim. Some find having all their weight on the plate is great, others find having a belt with a few pounds helps trim them out. This will vary depending on the tank you use.

My plate weighs ~11 lbs., and I typically wear a 8-12 lbs belt depending on the tank I'm using. I like having some weight on the belt especially if I don the gear in the water. I wear my belt under the harness, so I have it on when I enter the water. With no weight on the belt your kinda pinned on the surface.

Wings or BC's or Buoyancy Compensators, are required to "compensate" for the buoyancy your exposure suit looses as you descend. As long as your weighted "neutral" at the surface with no air in your wing, the max buoyancy you can loose is the lift your suit provides. How much lead does it take to sink just your wetsuit, i.e. without you in it?

Same holds true for dry suits. How much lead does it take to sink just you in your DS without any other gear, at the surface? Even if you flood the suit it won't loose more than this amount.


Regards,



Tobin

As far as the cam bands, thats great to know. The sp cam band grabs the tank great without the need to wet it first. As far as the weight is concerned, my reason for asking was because I heard reference to acb pockets which I had assumed went onto the harness somewhere and contained soft weight?
And while I am at it, I see oms wings seem to attach with a bungee that goes all the way around the air cell while others do not. Do others sorta "lace" up around the perimeter of the plate?

 

[hermosadive]

The SS hammerhead bp with sta will weigh in at 12 with the harness and d-rings. I too hated weight belts, but I now only wear 5-10lbs on the belt depending on which tank I use. I really don't even notice it anymore since it is so light. I know some people who weight their plate with v-weights or trim weights and pass on a weight belt altogether.

I'm not the expert on wing lift for your configuration, but I presently use an Oxycheq 30# wing and it floats me (250) and a steel LP95 without any problems. I doubt you would need nothing bigger than a 40-45# if you don't think a 30# would work.

 

[oversea]

Well my current weight is 225,6'-0" tall, and a bit out of shape. I usually fluctuate between 212 and 225 between summer and winter.

 

[Doc Intrepid]

As far as the weight is concerned, my reason for asking was because I heard reference to acb pockets which I had assumed went onto the harness somewhere and contained soft weight?

And while I am at it, I see oms wings seem to attach with a bungee that goes all the way around the air cell while others do not. Do others sorta "lace" up around the perimeter of the plate?

First, you should take a look at Tobin's plate. It's pretty innovative, and the bolt-on weights allow it to function either as a heavy plate or as a standard 6# plate. Flexibility can be beneficial - you never know how you might be diving 3-5 years from now.

Second, when you're talking about 'weighting' with a bp/wing, you're talking about two separate issues. You first need to determine that amount of weight which allows you to achieve neutral bouyancy - equilibrium - while holding a 10' safety stop at the conclusion of your dive: e.g. tank(s) nearly empty, wetsuit expanded - so max bouyancy, etc.

Trim, however, is not a matter of how much weight you require, but where it's located. If you think of your body as a lever and fulcrum, with your center of gravity somewhere around your hips, you'll distribute the weight you need to achieve a horizontal trim by using a combination of backplate (a heavy plate distributes more weight flat against your back, which can aid stability), trim weights (V-weights or P-weights, also called 'channel' weights), weights strung onto your webbing somewhere, or weightbelts. How long and heavy the tanks are that you're wearing also factor into trim, as well as where you're wearing them in relation to the backplate. That's a bit simplistic, but you get the idea. Where you put the weight depends on factors unique to you and your gear - no one can get on an internet chat board and tell you the best place to put your weights. You need to borrow some gear, get with a mentor or more experienced diver, and try a few things out. Otherwise, you'll end up like the rest of us with a closet full of expensive gear that you ultimately found out wasn't exactly what you needed. FWIW, any weight that is bolted to your tanks, bolted to your backplate, or strung onto your harness webbing, isn't 'ditch-able' in an emergency. Only a weightbelt is truly 'ditch-able' weight. If being able to jettison weight in an emergency is important to you, plan accordingly.

Third, wings don't lace up with bungee around the perimeter of the plate. Wings bolt between the plate and the tanks. When using a STA, the wing bolts between the STA and the bp. The subject of bungee wings can be controversial. The idea is that the bungee lacing collapses the wing when deflated, keeping it tucked in streamlined against the body. It works, to a point. There may be a few consequences. First, orally inflating it can be interesting (given that if you're orally inflating it you're having a bad day to begin with). Second, if slit or punctured - ....."the bungee lacing collapses the wing, keeping it tucked in against the body". Third, when attempting to deflate the wing, the tucks and folds created by the bungee can tend to trap air at random points inside the wing, which may make it more challenging to maintain trim. On the whole, many feel that bungee wings create more problems than they solve. If you're undecided, review videotape of divers wearing bp/wings. You'll note that non-bungee wings simply fold up against the tanks, and seldom present any significant drag while underwater.

Best of luck with your transition.

Doc

 

[Green_Manelishi]

Trim, however, is not a matter of how much weight you require, but where it's located. If you think of your body as a lever and fulcrum, with your center of gravity somewhere around your hips, you'll distribute the weight you need to achieve a horizontal trim by using a combination of backplate (a heavy plate distributes more weight flat against your back, which can aid stability), trim weights (V-weights or P-weights, also called 'channel' weights), weights strung onto your webbing somewhere, or weightbelts. How long and heavy the tanks are that you're wearing also factor into trim, as well as where you're wearing them in relation to the backplate. That's a bit simplistic, but you get the idea. Where you put the weight depends on factors unique to you and your gear - no one can get on an internet chat board and tell you the best place to put your weights. You need to borrow some gear, get with a mentor or more experienced diver, and try a few things out. Otherwise, you'll end up like the rest of us with a closet full of expensive gear that you ultimately found out wasn't exactly what you needed. FWIW, any weight that is bolted to your tanks, bolted to your backplate, or strung onto your harness webbing, isn't 'ditch-able' in an emergency. Only a weightbelt is truly 'ditch-able' weight. If being able to jettison weight in an emergency is important to you, plan accordingly.
Doc

Sage advice from the good DocIntrepid.

I'd encourage you to try a DUI W&T system for your weightbelt needs. The design allows you to place "trim ballast" on or below your hips witn no fear of losing the
weight.

 

[oversea]

Sage advice from the good DocIntrepid.

I'd encourage you to try a DUI W&T system for your weightbelt needs. The design allows you to place "trim ballast" on or below your hips witn no fear of losing the
weight.

I looked at the W&T system from DUI, it is interesting. What is a v and p weight? I was looking at some of the oms pockets to add to my harness but thats just an idea.