Tropical diving weight and trim issue

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eelnoraa

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I just came back from a tropical live aboard trip. I had this weight and trim issue, I wonder if it is common or if you guys have better solution for me.

My issue is being leg heavy by a big margin. With 3mm full suit, AL plate, SS STA, canister, no additional weight. My fins are OSM slipstream, one of the lighter DIR fins. I have spring straps on, not sure if that makes a difference. In order to counter that, I put 2lb on my upper tank band. Even with that, I need to breath from the bottom of my lung (not very comfortable) and with my arm fully extended forward to keep me in trim. If I take a deep breath, say when I want to ascent, my upper body will ascent and my legs will stay where they are unless at the same time I do a few small back kicks to raise my legs. Does this sound normal to you guys? If not, should I lose the spring strap? or switch to even lighter fins? or move weigher further up my body (how)?
 
I had similar issues with very similar set up. My solution was to place a 2lbs weights on both cam bands. This was sufficient in balancing my trim but then again I wasn't wearing an exposure suit. They'll be many more experienced divers here on the forum who may have more suggestions, I have always found that it's a matter of trial and error. Good luck.
 
I also have this issue when diving tropical waters. The solution is to just add a few more pounds to the top cam band until your trim is more comfortable.

The 3 mm suits don't compress much at depth so you don't loose much buoyancy and being a couple of pounds extra overweighted should not compromise your ability to swim the rig up in case of wing failure.
 
Alum 80 / Halcyon Alum plate, STA, STA weight (6lbs), primary light 21w (2.5lbs), cam band pockets (lower band / 2lbs each), and scout back up lights (?lbs). This is with a 3mm full suit with pockets and OMS slipstreams. Alum 80 / Halcyon Stainless plate, STA, STA weight (6lbs), primary light 21w (2.5lbs), cam band pockets (0lbs), and scout back up lights (?lbs). Again with 3mm full.....
 
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Also, if you have your legs stretched way out behind you (like most pictures of doubles drysuit divers in good trim) then you'll be generating more torque off the negative fins, if you bend at your knees more and pull the fins closer to the bottom of your tanks, you should be better balanced.
 
Sounds to me as though you might be a bit underweighted, too. I don't know how much the STA weighs, but I know that, in a 3 mil suit with an Al80 and a 5 lb stainless plate, I need to carry an additional 2 lbs. If you're wearing more neoprene than I am (I'm 5'4") I could easily see you needing more. Put it on the cambands, and you should be golden.
 
Many GUE instructors want the first strap at the crest of the tank but i tend to side the tank up a bit. It seams to trim me out better and I can reach the valve better.
 
My issue is being leg heavy by a big margin. With 3mm full suit, AL plate, SS STA, canister, no additional weight. My fins are OSM slipstream, one of the lighter DIR fins. I have spring straps on, not sure if that makes a difference. In order to counter that, I put 2lb on my upper tank band. QUOTE]

I would add 2 more pounds on the left side of the harness to compensate the canister, or a belt with 3/4lbs as I don’t think the 2lbs on the top of the tanks would do much. Then do the basic check.
I remember everytime going back to tropical I do the first dive thinking I don’t need weigth, then add too much, then reduced! But never put enough thinking into it beyond the fact “waouw, it’s cool, I feel I’m diving with nothing, do I really have a tank ;-)
 
2 lbs to counter the canister? Come on. If that was a real thing, I'd need lead on my left to counter my 13.5Ah can, then I'd need to counteract heavy stages with weight on the other side, then take it off when they got light, then put it back on again when I picked up my deco bottles. In real life, you don't have to do any of that. The wing does it for you.

A neat thing about wings is that you can put a bit more gas in one side or the other, eliminating all these "problems".

Keep it simple, guys.
 
I had similar trim issues. Solved it (mostly) by adding weight on the top cam band until I balanced out. I was probably a tad over-weighted, but I was diving my Hollis F1 fins so I needed more weight up top.

Henrik
 
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