Buoyancy

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You've had a lot of advice given, mostly relevant to the sort of diving you are doing.

As suggested above, a dive that is devoted to tuning your weighting and trim would be a good start. Weights can be moved around as needed and you'll benefit from an experienced eye watching what you do.

Drysuits add a bit of extra complexity with air moving around inside but it's just practice. You can achieve quite a lot of trimming just by moving your arms from out in front to down by your waist.

It'll be good if you can report back on progress.
 
You might have quite a bit of gas trapped in your drysuit, especially if the suit doesn’t quite fit. The gas bubble will move around and make you feel unstable. Try getting yourself almost shrink wrapped - unless you are using your drysuit for buoyancy, you should be keeping the dump valve almost open (fully open, back off few clicks), make sure that you dumped all your gas from BCD and that you are not kicking upwards.

Do a buoyancy check at the END of the dive. With a minimum amount of gas (30-40 bar), you should be able to hold 3-4 meters depth with empty BCD and squeezed drysuit, without any kicking. If you are sinking, you are carrying way too much lead.

19kg is a lot with steel cylinders, you might be pretty overweighted.
 
Trim first. You should be mostly horizontal, knees bent, with your legs higher than your torso. You should be prone, so face plant sounds about right.

Our entire life is lived upright as opposed to being horizontal. We're just not used to being prone and it feels unnatural. It's time to relax and lay on your stomach on the floor to get the feeling of being horizontal.
 
Thanks for everyones welcome. Glad ive found a place to ask questions without getting abuse. There are some divers who seem to think they are above others as they have been doing it a while. Iam diving again on Wednesday so will keep practising and making adjustments. My drysuit is second hand and was custom made for someone else so doesnt fot the best but its all i have for now.
 
You should really deal with the real issue which is the obesity. Losing the weight with a proper diet and regular exercise will not only help your buoyancy but allow you more time to enjoy the sport as you get older and your body starts to show the effects of the uncontrolled weight gain in the form of muscle and skeletal problems and of course inevitable cardiovascular issues often coupled with diabetes which results in further problems.
 
Definitely run the suit vent mostly (if not all the way) open. When I level out from a depth change, I just give a little roll, listening for a few bubbles to escape. If none do, inflate the suit until they do. This is enough to loft my undergarments but not enough to make a bubble that will dart toward my legs at a moments notice.

Doing a weight check is a drysuit can be tricky, because going heads-up tends to vent the suit beyond what was correct when horizontal. If this is happening, just vent while horizontal, then temporarily close it by perhaps 5 clicks. This will mostly retain the same buoyancy even though air is driven out of your legs when they drop. Again, you're looking to first understand the TOTAL weight required (with empty BC & tanks).

After you figure out the total weight needed, then you can deal with distribution. The harness will help with that, as it's easy to lower it. The crotch strap is another option to get weight low. Negatively buoyant fins are extremely common for drysuit divers in a backmount configuration; Jet fins or F1s.
 
Where should weight be positioned? I dive with a steel cylinder, trilaminate drysuit, i have a fleece undersuit. 15l and a 12l cylinder. Ive tried doing weight checks
Is the 19kg in addition to the steel cylinder? Also are you diving backplate and wing or jacket style BCD?
 
In a drysuit, I have found what helps is:

  • Negatively buoyant fins like Jetfins
  • Legs bent just slightly. Keep the weight of those negative fins away from your torso so they have more leverage.
  • Arms out like Superman - your hands are floaty, so give them leverage to keep your head up.
 
I don’t have a lot to offer here because it sounds like your circumstances are quite different than anything I’ve experienced. However, I will say asking for help is a great first step! Buoyancy/weighting was a big struggle for me in the beginning of my diving journey. As many of the other posters have said, gaining confidence in the water will help with being able to shed some weight. Being overweighted can have a huge impact on your enjoyment of the sport. The thing that helped me the most was just taking every opportunity I could to get in the water and try different things. That’s essentially what everyone else is saying here with more specifics. Just wanted to offer some encouragement. Just keep getting in the water and you’ll keep learning more about yourself as a diver.
 

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