Perfect buoyancy

[Bob DBF]

However, I felt a tad light at the very end of my dive (tank buoyancy). 8 lbs is what I had been diving with in the past and was a bit heavy on that. Should I try to find a 1/2 lb weight for each side?

I have some 1# weights and just round up when adding to make it even. A pound over is a negligible difference, and better to be over than under.

If you dive a wetsuit, especially a thick one, it makes a difference what depth you dove what it’s positive buoyancy will be on rebound, when doing a weight check at ten feet.

I like to separate buoyancy from weighting because there are only two conditions where weighting affects neutral buoyancy. First is when one doesn’t have enough weight to hold a stop, second is when one has so much weight it exceeds the capacity of the BC to float the rig and diver. Neutral or perfect buoyancy can be achieved between these extremes.



Bob

 

[David Novo]

If you dive a wetsuit, especially a thick one, it makes a difference what depth you dove what it’s positive buoyancy will be on rebound, when doing a weight check at ten feet.

The buoyancy of a wetsuit is not the same at 10 feet after a dive to 100 feet or to 50 feet?

 

[Bob DBF]

The buoyancy of a wetsuit is not the same at 10 feet after a dive to 100 feet or to 50 feet?

It is not. It’s a matter of how much the suit compresses at each depth, and how much positive buoyancy is regained as you surface. It won’t regain its full buoyancy for some time after you surface and put away the suit until your next day out.

This will also change over time as the wetsuit material breaks down. You can feel it at the safety stop if you do a weight check every time you surface.

 

[David Novo]

It is not. It’s a matter of how much the suit compresses at each depth, and how much positive buoyancy is regained as you surface. It won’t regain its full buoyancy for some time after you surface and put away the suit until your next day out.

This will also change over time as the wetsuit material breaks down. You can feel it at the safety stop if you do a weight check every time you surface.

So, a weight check should be done in the end of a shallow dive, not a deep one, correct?

 

[Bob DBF]

So, a weight check should be done in the end of a shallow dive, not a deep one, correct?

Just weight for the depth you are diving. I check most every dive, over time you get a feel for the difference, and a few pounds over what you find to be perfect at the stop, is no big deal.

 

[Degenerate]

Agree, also, personally at this time of the year I like to be able to hold my stop with a bit of air in my drysuit: I feel really cold if I hold it without air in my drysuit.

Dont know if this is wrong.

With steel doubles and a drysuit my only weight is 2,1kg backplate and 2kg butt weight.
I can hold my last stops with a comfortable amount of air in my suit down to 20 bar.
I used to dive without the butt weight but as you said, having some extra air in the suit on the stops made a big difference in how comfortable I was.
Almost exclusively dive in fresh water, if I end up in salt water I will go with a 3kg butt weight instead.

I would pick a couple kilos too much rather than a half kilo too little every day of the week, a little bit extra drag from the wing is a non-issue on a regular dive when compared to the benefits mentioned above.

 

[scubadada]

Agonizing over that last pound or two is just not worth it. You want to be easily able to hold your safety stop with a near empty cylinder and also make a slow, controlled ascent to the surface. I've got my diving down to a very simple formula, with an AL80, I dive 8 pounds with my 3 mm +/- my 5/3 hooded vest, 14 pounds when I switch to my 5 mm, and 20 pounds when I switch to my 7 mm. Of course, I could probably take off a pound when not using the hooded vest. I could probably even trim a pound at other times. However, I don't need a whole lot of gas in my BC at depth, I can easily make a good ascent with a little venting, and my SS and final ascent are a piece of cake. No muss, no fuss, works perfectly. I occasionally dive with a HP100, I just reduce my weight by 4 pounds, 4, 10 and 16 pounds, works perfectly and simply. I'm never too light

 

[TMHeimer]

It is not. It’s a matter of how much the suit compresses at each depth, and how much positive buoyancy is regained as you surface. It won’t regain its full buoyancy for some time after you surface and put away the suit until your next day out.

This will also change over time as the wetsuit material breaks down. You can feel it at the safety stop if you do a weight check every time you surface.

Yes, I mentioned how I have a little trouble descending with a dry wetsuit, and now that I think of it, descending on the 2nd dive goes a lot quicker. Also note that with my first wetsuit (lasted 10 years) I needed 42 pounds as a new diver and 37 after the 10 years. Figured it was what they usually say about dropping weight as you get more experience. Buying the new suit and having to go back to 42 pounds confirms my thought that unless you're overweighted at the start, experience really has nothing to do with required weight.

 

[Bob DBF]

If you want to add a little more uncertainty into the game, start weighting your dive weights. The results more interesting if you use old or backyard made weights.


Bob

 

[BRT]

If you want to add a little more uncertainty into the game, start weighting your dive weights. The results more interesting if you use old or backyard made weights.


Bob

We started carrying a scales on dive boats before we just made sure we had our own weights.