Question on weighting for no BC diving

[Luis H]

I’m pretty sure the very first scuba techniques including backpack diving grew out of skin diving.

That is correct.

I still initiate all scuba dive with the same technique I use for free diving. I dive head first while raising a fin out of the water to help go down. I don't over weight myself so, even with fully exhaled lung volume, I can not go down feet first to start a dive (when I start a dive my wetsuit is not compressed and it is not totally wet).

 

[aquacat8]

That is correct.

I still initiate all scuba dive with the same technique I use for free diving. I dive head first while raising a fin out of the water to help go down. I don't over weight myself so, even with fully exhaled lung volume, I can not go down feet first to start a dive (when I start a dive my wetsuit is not compressed and it is not totally wet).

Same here. That’s also why I can keep my air2 on my wing lightly bungeed: my go to dump valve is the rear. Ascending I used to use it, but now I tend to be horizontal and breathe up, ready to gently tip down and rear vent if needed.

 

[aquacat8]

To my mind it makes no sense to be in a heads up position if you are trying to dump buoyancy, because gently finning down controls it while you’re dumping. In a heads up position if you move your fins at all you’re swimming UP.

 

[captain]

No BC diving.

 

[Bob DBF]

I’m pretty sure the very first scuba techniques including backpack diving grew out of skin diving.

Actually SCUBA diving was also called skin diving back then. The terms skin diving and free diving were references to diving without the diver dress and umbilical used in hard hat diving. The useage has changed over the years.

Underwater swimming and snorkeling were used dependant on whether you had gear or not. I spent a lot of time underwater before I got my first mask and fins. The snorkel left a bit to be desired with its state of the art float ball in cage at the top, eventually it was cut off.

Bob

 

[JamesBon92007]

Steel 72s are pretty easy to find. Keep an eye on the local for sale papers, they show up fairly often and unless abused, even very old ones are usually fine.

I just want to add: get one that is galvanized! Also, no liner is better but it's hard to tell from looking at the outside of the tank.

 

[JamesBon92007]

Reading the comments makes me wonder if I was doing it wrong for over 40 years! I never actually calculated how much weight I would need but my results match the descriptions given here. On the first dive I'd take a good guess and decide if I was too light or too heavy and add or subtract a couple pounds for the next dive. Then I would never think about it again until I changed wetsuits. Decending was as Luis H described. I was amazed and surprised the first time I used a BC at Molokini and everyone was holding their BC hose up and letting out the air. You also have to realize that, way back when, nobody cared if you were slightly negative and rested on your knees on the sand (at least not here in SoCal). When I got my first AL80 I had to add a couple more pounds but kept it the same if I used a steel 72.

Here's me, later on in my diving career, after I had gone "high-tech" and had a SPG and depth gauge. At that time (early 80s) some people had jacket BCs but I couldn't understand why anyone would want to try to get through the surf with one. Backwings had been around for some time but those were mainly for diving double 72s. I'm wearing a full 1/4" farmer john with 1/4" hood and booties. No BC was simply not an issue.

Jim Scuba 1985

• JamesBon92007
• Sep 4, 2016
• 5

Me in 1985. I still have the same mask, snorkel, booties, and regulator! It was taken with an...

I'm still wearing the low-volume, small nose, clear skirt mask you seem to be looking for It's an old Cressi Occhio. I think they only come in black now.

 

[aquacat8]

No BC diving.

wow that was incredible! I love that film, so beautiful, real work of art, and great music… I think that was a theremin! Thanks so much!

 

[Eric Sedletzky]

I think that video clip of JYC pretty much sums up the minimalistic elegance of no BC diving. Gliding around, legs out straight, nice full standard fin kicks with body pointed towards direction of travel, unencumbered slipstream moving through the water effortlessly with minimal gear, only tanks strapped on the back, nothing more nothing less. That was the standard.
It worked beautifully then and no reason it cant work just as well now.

Currently, all the rage is elevator diving. They even have levers labelled as such!
Corruption of time and technology.
Skydivers underwater who god forbid never get out of “trim”.
Flat all the time.
Do sea mammals stay flat all the time or do they swim?

 

[Bob DBF]

Skydivers underwater who god forbid never get out of “trim”.
Flat all the time.

I like the definition of trim as neat and smart in appearance; in good order. No where in there does it say flat all the time, that part is a construct of some agency. To get from point A to point B, a straight line may be a 45 degree angle with a corkscrew turn around a large boulder to the objective behind it, I believe proper trim would be at the 45, with a yaw to face the boulder on the way around correcting to the objective on the other side. I've watched seals do it and that's what they do for a living.

Do sea mammals stay flat all the time or do they swim?

They swim, and they are damn good at it. I try to learn as much as I can from them, but I'm not as good a student as I should be.


Bob