Buoyancy

[dmaziuk]

 

[The Chairman]

Can I quote you on a FB note, with a link to your comment? This is useful stuff.

Of course. All this should be a part of any OW course. It's not hard, but it's certainly hard to dive intelligently without knowing about it.

 

[wetb4igetinthewater]

Of course. All this should be a part of any OW course. It's not hard, but it's certainly hard to dive intelligently without knowing about it.

I do weighting a little differently, but wanted to share this nonetheless.

 

[The Chairman]

This is a great demonstration on why to use the least amount of weight possible. The less air you have in your BC to maintain neutral buoyancy, the less there is to compress as you dive deeper. I rarely use any exposure protection and I rarely have any air in my BC. Ergo, my depth rarely impacts my buoyancy. I can descend to 130fsw and back up to the surface using only my breathing.

 

[The Chairman]

I do weighting a little differently, but wanted to share this nonetheless.

Whatever works, works. BTW, I noticed a huge typo in one post. Male average vital capacity is 4,600ml, not 2,600ml. It's still 10 pounds of buoyancy, I just copied the raw data wrong.

 

[dmaziuk]

This is a great demonstration on why to use the least amount of weight possible.

It's a cool demo, isn't it? I was googling for densities of Al vs steel vs water and that came up.

 

[BalekFekete]

So much good information in the thread - to everyone who added in the pearls (special nod to Pete!) thanks! My wife and I are still very green divers (~20 dives to date) so any type of good info., tips, or tricks is appreciated! We're doing our AOW next week so I'm hoping to get my bouyancy and trim into a better spot sooner than later (as is clearly needed as evident in my profile pic... ).

 

[The Chairman]

Take a foam cup diving with you. The crush is largely permanent on the styrofoam and you can see the before and after.

 

[scrane]

And we completely disagree.

Most of the cool stuff is close to the bottom, and often under outcroppings right at the bottom. You can't see it unless you're really flat. As for looking ahead, tilt your head 30 degrees to the right or left before you try to look straight ahead.

Rototillers was the name given by our dear old @Uncle Pug for those who were determined to dive with their feet down. Why? When they got close to the bottom, the thrust from their fins stirred the bottom and utterly destroyed the visibility behind them. Oh, they had great vis, but not anyone who was behind them. More often than not, they had no clue of the devastation in their wake. There is a discussion way back in time, where a guy claimed that he just doesn't silt others out when diving with his head up, legs dangling and then his buddy chimed in. It was truly a candid discussion. Denial: not just another river in Egypt.

So, some get the important relationship between trim and buoyancy and others just don't. Master trim and buoyancy and watch your control, comfort and fun increase significantly. That, or let the vagaries of Boyels law and vector forces master you.


I beg to differ on this, but that position is pretty standard the world over. It shouldn't be, but it is.

Well, sometimes I dive sideways, and sometimes upside down. Never use my fins to maintain depth in my vertical position. This is a matter of buoyancy control, not trim.To me always diving in horizontal trim is like viewing the dry world from face down on the floor.
I admit that drift diving works best for my vertical trim. Swim throughs also require some compromise on my part.
Essentially, I adjust my orientation as conditions demand. People who maintain horizontal trim at safety stop and descent leave me scratching my head.

Dive and let dive. Join the revolution.

 

[scrane]

Caveat: I do go vertical on every dive, once I'm on my deco stop, whether it's mandatory or precautionary. I rotate and look for approaching boats as I ascend from that stop.

If you ever need any tips on vertical trim let me know. You seem to have some misconceptions.