Let's discuss peoples over-reliance on BC's and over-weighting.

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Typically this is someone who has only dove in cold water and thick wetsuit and then comes to Florida with a shorty and tries to use the same amount of lead.

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Hard to believe some things I have read. Maybe it IS rocket science???
 
It is simple physics. Your buoyancy changes during a dive because A:The weight of air in your tank changes B:Your suit compresses. You can swim up and down and breath at the top of your lungs and the bottom of your lungs but you cannot maintain proper buoyancy without a buoyancy compensator.

Partly correct - yes, your buoyancy changes with depth and tank pressure / volume changes and I assume we're talking wetsuit diving but we've been diving for many, many years and to depths well beyond recreational "rules" with no BCD's. It takes discipline, a lot of experience and a lot of practice and it is no more "unsafe" than any other kind of diving. Most of the guys and gals you see doing it are solo divers too for some reason - regardless, they're usually the old timers and have hundreds or thousands of dives in all kinds of conditions. Probably got their BOW cert in the early 70's or earlier - before the stab jacket came on the market
 
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I see very little interest in new divers learning proper weighting. Most are assuming that a diver without a BCD going into the water is "nutso" or forgot it or something.

As far as why instructors don't teach it - it's, IMO, because it takes extra time and even most instructors nowadays may be very new with only a few hundred dives under their belt themselves.
 
As far as why instructors don't teach it - it's, IMO, because it takes extra time and even most instructors nowadays may be very new with only a few hundred dives under their belt themselves.

In my OW course I remember almost nothing being taught about proper weighting (and trim). During OW checkout I was vastly overweighted and it really sucked. Impossible to maintain good buoyancy or trim.

Later, I was fortunate to get advice from someone who is said to have the absolute best buoyancy/trim skills ever. She got me to do nothing but work on buoyancy till I had my weight perfect. Then move weight till my trim was perfect. Then continue to practice till control was second nature.

Now I'm embarking on a new adventure with it's own learning curve. I got a backpack soft plate, harness, cam bands and I want to learn to dive without a BC. I'm going to Bonaire for two weeks and will dive with my BC from boats (when/if I do that) and deeper than 20-30 feet. But I want to devote a dive or two each day to practicing without a BC.

Once again weighting & trim is going to be key. I'll spend as much time as necessary with an "empty" tank (500psi) till I get the weight perfect - I'll bring some of my own weight in 0.5# increments. Then I'll work with a full tank to see how much more negative that makes me. Next, I've got 4 weight pockets to move the weights till I get perfect trim. Finally, I will have to figure out some buoyancy trick to make up that difference at the beginning of the dive that I can bleed off as the tank empties.

I'm disinclined to use a horse collar or snorkling vest because I don't want the front of the rig covered. I'm thinking a small SMB rigged down the front. Put enough air in it to offset the extra negative buoyancy at the start of the dive and let air out as needed. If anyone has a better idea I'd love to hear it.
 
sounds silly. If you want to experiment with no BC, just empty the bladder and don't add air and dive. Swimming around with an smb; inflated and sticking up in the water column will accomplish what exactly?
 
... So it is not beneficial to wear too much lead, but I think there is a somewhat blurry line between being "over" weighted versus just carrying a little extra lead...
As you say, the determination of "over" for those last few pounds becomes a matter of choice and circumstances - a trade-off of flexibility to reduce bouyancy, against maximal stability when neutral. Still as has been pointed out, many divers don't appear to have nearly found the best balance as can be comically- or painfully - evident. It took a blown BC at the beginning of a live-aboard trip to open my eyes to just how much weight could be jettisoned yet still have control at depth. Descents and safety stops were a challenge - fortunately there was usually abundant kelp to make use of, and I learned that those "plunk and gone" entries favored by the rest of the divers could be more than just cool stylin'.
 
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Was the ability to hold a motionless hover seen as big of a deal in the "good old days" as it is today?
 
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@Kharon usually slowly swimming is enough to compensate for the extra lead needed for a empty al 80, in my experience.
 
I had posted this in the vintage section. I started diving before BC existed, I also dove with 5 mil wet suits. It was never a big issue.
In the beginning it was pure freedom.

 

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