Buoyancy issues...

[Greenwood_60]

I, in general, have buoyancy/trim issues. My problem starts with 1) I sink. In fresh water, with no gear, I sink with a full breath of air. With a 3 mil shorty, I float with a full breath of air, and sink when I exhale. The problem is I have not only a large bone structure, I also have very dense bones. Never broken a bone, probably never will (going on 18 years of Football, peewee, HS, 1AA college, semi-pro).

My problem with trim is that my legs are considerably less buoyant then my upper body. I have not found any weighting scheme that will get my legs up. I have even though about strapping sealed PVC cylinders to my ankles to get them up.

I am trying to get all my skills in order to start my cave cert, but this is really sticking me. Anyone have any ideas? Am I just a NOOB, to be schooled on the errors of my ways? Or is my "I'm just big boned" excuse legit?

[Superlyte27]

What gear are you diving? B/C, BP&Wing? Singles, Doubles, Aluminum tanks, steel tanks? give us some more info.

[WJefferis]

Also, what kind of fins are you diving with? When I switched over to sidemount I still had a pair of ScubaPro Jets and they were so heavy I would pretty much naturally sit vertically in the water. Once I bought a pair of Dive Rite fins (tons lighter) I was perfectly trimmed out without a problem.

You will be able to correct you trim without strapping PVC pipes to your ankles. Beware that if you do you not only will you be laughed out of cave country I couldn't imagine someone certifying you with them attached to you.

Trust me I have seen very large guys in full cave gear totally trimmed out so your big boned theory just doesn't hold water (pardon the pun). Depending on what kind of gear you have it will most likely just take some tweeks here and there to get you dialed in. So list what you dive with or even post a pic of you wearing your gear.

[AB8CD]

I find that it's about center of gravity. You can adjust gear and weights in many ways. e.g. a v weight in between your doubles moved up or down can impact center of gravity, attaching weight to your harness in the small of your back or on your chest straps can offset heavy legs. Generally, it's about moving weight around your kit, however, the amount of air volume in your mask can effect fine tuned trim. And finally, there is some magic involved with controlling center of gravity inside your skin that just takes time in the water to become second nature. BTW, just about the time you begin to feel as if you've mastered a skill, your kit will change and you take a step or two backwards.

[Meister481]

I've got the same issue. I've found that a steel plate and having the tanks all the way down in the bands helps a bunch. Diving SM makes it worse, I had to put trim weights on my Nomad webbing. Some plates have attachment points for addded weights near the bottom. Last resort would be to weight your crotch strap near the attachment point.

All it takes is a mentor or decent instructor to get you trimmed out properly. Life in an overhead environment is much easier with good trim.

[Greenwood_60]

Haha... I saw the PVC tubes attached to a DPV and thought it would be a ridiculous solution. Never serious about the PVC... although I was thinking more seriously about thicker booties. My fins are very heavy, and negatively buoyant. I was reminded of that at paradise springs on Friday, and had to don my pony bottle to retrieve one.

My gear: Rec/Tec style back inflate bc, integrated weight, 5 mil full, 5 mil booties, 3 mil hood. It got better when I went from a 3 mil shorty that I have been diving the springs in for years, to the 5 mil full. It got worst when I added the hood. Oceanic Splits (I know, I know, they will kill me). When I had a stab jacket bc, and weight belt, it was so bad I had to hike my tank up where my 1st stage would sit above my head. I use both aluminum 80's and steel LP 72s. I have a set of LP 104s that I plan to break down and install my new H-Valves on. They sit filled to 3300 with 33% EAN. Anyways, regarding the AL80 vs Steel 72, doesn't seem to make much difference.

I have a BP and Wings sitting in the closet, but I need to pick up a single tank adapter before I start using that.

I not a really big guy, seriously. My perfectly functional (with everyone else) combination weight/body mass/bone mass/body water scale gives me all the readings then errors on bone mass. Works for everyone else.

[AB8CD]

Last resort would be to weight your crotch strap near the attachment point...

Couple of cannon balls should work...

[Parolles]

Oceanic Splits (I know, I know, they will kill me).

I love my Oceanic split fins for open water / ocean diving, but they are about the heaviest fins I've ever handled. Maybe try some lighter ones and see how it feels? You're not going to wear those into N. FL caves anyway (if they're the like 2+ ft long ones I have).

[stairman]

Feet heavy? Move tanks up, 7mm booties, knee pads, Dive-rite fins, harness weights, be sure back is arched, move wing down.

[Greenwood_60]

I don't understand how adding weight below my waist will help? I can see adding weight around my chest, as well as ditching the uber heavy Oceanic splits. I have a set of the bigger scuba pro jet-something fins, but I have not tried them out yet. They also seem very heavy/dense.

I do have 2 pockets about mid way up my back on my BC, but adding weight always seems to have the same effect of rolling me over on my back. Tried it with the 3 mil, no luck, tried it again when I switched to the 5 mil, SOL there too.