How to perfect buoyancy and trim

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DriverDiver

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Don't flame me too hard. I know it is a dumb question. Looking for suggestions on how to get trim and buoyancy down to tech level perfect. It is slowly getting better the more I dive but I would like perfection.
 

Colliam7

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Not a dumb question at all. In fact, it is one that is frequently, and appropriately, asked.

Three comments to start the discussion.

1. A key ingredient in optimizing buoyancy and trim is optimizing weighting - both total amount AND distribution. Too often, weight is improperly positioned, below the center of lift (the thorax), which pulls the legs down and results in a head-up trim.

2. Positional perception is not always accurate. I regularly tell students that, 'If you feel that you are perfectly horizontal, chances are that you are slightly 'head-up'. If you feel like you are slightly head-down, chances are that you are horizontal.'

3. Video is a big help - have a dive buddy get in the water with you, and video you - holding your position, finning, etc.
 

The Chairman

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Jay

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Patoux01

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Find an underwater camera. Alternatively a large mirror. And then correct from there. Unless your gear is absolutely ducked up, it is usually a matter of perception and correcting rather than moving stuff around on your gear.
 

АлександрД

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I`d used very simple way in the pool trainings.

Use short wet suit, with opened knees.
Than start to swim on the distance from the floor not over 5-10 cm (2-5 in)
Ideally - when you will touching the floor (in the beginning) just with belt buckle on your belly.

As you will try to bent into "seahorse" pose - as you will immediately had knocking by your knee on the tiles on the floor.
After some most strong hits, you will receive very stable reflex to stay your body in proper pose :)

This method usable after you learned "so called cave" frog kick with fins above you body line.
 

kensuf

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1. Get your weighting set to ideal. Most people wear way too much lead, which they compensate by putting tons of air in their BC. That volume of gas shrinks/expands with even the slightest depth changes (and it's much more dramatic in shallow water). So adjust your weight to ideal -- that means with only 500 psi you can maintain neutral buoyancy in 10-20' of water with no air in your BC / Wing. I personally find the easiest way to do this is start with 1000 psi in a tank on a platform at ~20' of depth, dump all of the air out of my BC, and remove a pound at a time until I am weighted correctly. You need to also accept that on an inhale you will ascend slightly, and on an exhale you will descend slightly -- this is neutral buoyancy.

2. Move the remaining weights around to adjust trim. I have a lot of air space between my ears and in my chest, and none in my hips or legs. Weight on my hips with air in my head tends to put me in a head up / feet down position. Moving weight to my shoulders, or the top of the cylinder with trim weight pouches, allows me to put weight where there are air spaces, and remove it from places where they are not.
 

The Chairman

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Did they eventuate?
Not yet... I'm hoping to do the video needed in Cozumel in about a month.
 
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hroark2112

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One thing that (surprisingly!!) no one has mentioned - if you’re not already diving a backplate & wing, switch to one. A steel backplate will distribute 6# fairly evenly across your back right behind your lungs. It also reduces how much lead you need to carry on a weight belt (or pockets, whatever).

Oh...and practice practice practice!!! Remember to practice your basic skills while horizontal (mask removal, reg recovery, SMB deployment).
 
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