trim adjustment with BP/Wings

[detroit diver]

I just looked at that picture and yes, it is on backwards!

A slightly weighted STA will help you some. I'd be little leary of adding TOO much lead weight up there before you get your body position correct first. You might find that you don't need it.

Also, I put my upper tank band just under the point where the tanks begins it's curve towards the valve. But everyone's body is different. Be aware that VERY slight changes will affect your trim greatly. For example, I know of someone who moved his tanks (on a set of LP104 doubles) about 1/2 inch and he had to call the dive because he couldn't stay level and was fighting the whole way.

 

[Scubaroo]

merkin once bubbled...
...in it's current setup, from my spine the next thing would be the wing nut and then the center ridge. The sides of the BP are closest to my back not the center ridge.

You have the backplate set up correctly in that photo - look at the top edge of the plate. It's the reflecting flash hiding the shadows that makes the backplate look like it's reversed.

Of course you could always start using a steel tank, whch would move the center of gravity higher up your back, promoting a more level attitude in the water, because the steel tank (most of them anyway) stays negative throughout the dive. Moving an AL tank up your back could have the opposite effect - as you use up the gas, they become buoyant, and your center of gravity moves *lower* down your back - resulting in the head's up position you're describing. Think of an empty steel tank as a brick, and an empty AL tank as a balloon.

 

[MikeFerrara]

Body position will effect trim but if your not pretty well balanced body position alone won't help much. The exact arrangement required will differ a little from person to person but most need to get some of the weight off their waist. When the suit compresses you put air in the wing which wants to go up while the weight on you waist wants to go down. As long as you have these apposing forces there is no hope of achieving correct boddy position.

when I dive a single al 80 and a 2 piece 6.5 mil suit I only have 4 pounds on my belt. I have another 4 threaded on the upper cam band and sometime put an ankle weight on the neck of the tank. I haven't gotten around to making a chanel weight yet but that would be the best. Also IMO a steel tank makes more sense when wearing heavy exposure protection.

Get balanced so you can stop fighting then work on boddy position. As your body position improves you may find that you need to move weights around more but you have to start somewhere.

 

[merkin]

Thanks for everyone's input, it has proven very educational for me. Clearly I need to go play some more with it in the water.

One elliptical question about trim/body position. It is my understanding that ideally you want to be setup so that if you close your eyes, and completely relax, you maintain a horizontal orientation in the water without moving up or down the water column or listing/rolling to one side. I won't be completely relaxed, however, if I'm arching my back and bending my legs back to maintain correct trim. Although this might become "second nature", I would suspect that when I start doing all those DIRf drills (e.g. air share) this will be the first thing I dump from my attention span...

so what am I missing?

 

[crazyc]

Wow, that is bizzare how the flash made the BP seem inverted. Sorry about that one, I really though you had it backwards.

The first few times I dove in the DIR horizontal position it seemed wierd and akward and like everyone else has described, I came out of it with a slight nag in my lower back. Now it is so natural, when I am trimmed out, it feels very efortless. It came with a combination of getting my system balanced out which is what you are struggling with it sounds like and practice.

The biggest caution I have for you, is not to try every living thing in the book every dive. Make a minor adjustment and do a couple dives with it, unless it just drastically screws up your trim. I have seen more folks drive themselves insane trying adjustment after adjustment, when all they really needed was something as simple as loosening up their crotch strap. If you can get someone to go out and video you, that may help, but unless they are familar with the system you are using, it may add to the confusion.

Can you put your harness/BP on with your suit on and have someone take a few pics? That may help us see if you need to make a harness adjustment. Sideways, front and with you reaching one or both hands back to touch the top of the plate.

 

[detroit diver]

Thanks for the correction about the BP. I'm glad someone picked it up. It sure looked backwards even after looking at it a number of times.