Am I supposed to decend all the way to touch the bottom?

[PaulB]

I've been diving for a little over a year and I still practice my bouyancy. It is a very important part of diving so I try and practice as much as possible. Even when I had finally achieved neutral bouyancy, I still felt the need to fin and wave my arms around untill I became confident that I would just float there.

 

[jray]

try not to hit the bottom if you can avoid it.

 

[DameDykker]

Also squarepants if you need another insentive. In some parts of the world the sand can be full of little and not so little camouflaged poisonous crittes!

 

[Ari]

One should control his/her buoyancy all the way down. You should be able to stop yourself before hitting the bottom.

Reading your post, I wonder if you are not too heavy. I bet you are.

Just remember that the right weight is when you are able to float at 15' with your tank at 50 bar and no air in your BC. Once you get your weight sorted out, bouyancy will become easier, because you are more neutral all together.

do yourself a favor and get the time to work out your weights. It will pay off.

Ari

 

[herman]

Sound like you have gotten some good advise. A good check to see if you are properly weighted is in order. Crashing down or for that matter a soft landing on the bottom is never a good thing. If you have a quarry or other place where there is a dive platform, a couple of trips to get in some practice there would be a big help. A pool is another alternative. After 12 years of diving, I still practice every chance I get.

50- bar is a little over 700psi. Here is a web site with a conversion table if you are intersted. http://www.chromatography.co.uk/TECHNIQS/Other/Pressure.htm

 

[The Chairman]

really! Whether your descent is horizontal, vertical or inverted makes no difference... just be in control. You are compensating for Boyles law with every ascent and descent. Remember to add when you descend and vent when you ascend, which is opposite of our "logical response".

Lots of good info for at the end of a dive... but try this in a pool.

1) NO weights and NO air in your BC and with a full tank.

2) Cross your legs and hands so you don't kick or scull.

3) Breathe normally.

4) Have someone measure how much of your head is above the water line.

5) 1" = 1# so add the weight you need (just hold onto it for now)

6) Recheck and add/subtract until the top of your head just breaks the surface (make sure your hands and legs are not moving).

7) Remember that OW adds some stress and that adds buoyancy. Don't add more weight... just deal with the stress!!!

8) Saltwater needs more weight than fresh. Do the same thing on an ocean dive and you will nail your buoyancy.

 

[dreamin']

The question of being neutral still eludes me. I understand about being properly weighted and that everything varies with depth. I just purchased my first BC, Reg, Gauge and wetsuit (7 mil I'm an east coast quarry diver). I found that I could easily stay neutral to about 40 feet. Below that point I would sink with increasing speed. I sruggled to be neutral down to 60 ft. Below that it was like someone tied a brick to my foot. I sank quickly. My reaction was to keep putting a little more air into the bc. I just continued to sink. I finally just squeezed the inflator for all it was worth till I stopped at 80 feet. I eventually put a lot in and began to rise. I began to yo-yo trying to control my ascent. Once I got back to forty feet I was able to regain solid control. Is forty feet the point where the wetsuit begins to rapidly compress? I believe in retospect I was overwieghted. I cut back on the second dive but experienced much the same thing. It's funny I don't remember experiencing this much trouble with the rental eguipment. My purchase equipment is completely different from what I had been renting. Do I just need to learn the "touch" with the new equipment? Practice?

 

[wreckchick]

It sounds like you are reacting vs. acting. Once my descent has begun and I'm most definitely headed down, I add little bursts to my BC to keep the descent controlled until I'm getting close to my planned depth then add a little more, little more, little more until the descent slows and then stops. You should be adding air long before you reach your planned depth. The further down you go the more you need to compensate, but it shouldn't be all at once when you are 5 feet above your planned depth. I like my descent to be rather lazy, makes equalizing easier and I can stop almost on a dime if I'm having a good day.

When ascending I never add air to my BC. I fin up and vent as needed to control the ascent. If you start the dumping air to descend/add air to ascend, you're right and you will become a yo-yo in the water, as you've found out. You need to do the counter-intuitive thing and add air when you're going down, dump air when you're going up.

The best thing you can do is go to a training quarry, or a pool, and just practice ..... a lot. You do need time to get used to your new equipment, but the learning curve shouldn't be that steep once you're sure you're properly weighted. When you check your weight at the beginning of a dive, keep your hands still and cross your ankles. I watched a friend weight check in the pool and relieved him of 4 pounds because he was impeding his own descent by moving around. If you are on a platform or similar solid bottom at 15' at the end of a dive you can, with a buddy, literally dump air by purging your octo down to 500 psi and do an end of dive weight check. This is sort of like a fin pivot where you dump all the air out of your BC and pick up or drop weight until you start bobbing up and down with big, deep breaths.

Hope that helps!

Rachel

P.S. I realize I just repeated a lot of what NetDoc said. He's right.

 

[The Chairman]

as it is compressible. If you take out the air you take out the variance. Less weight means less air which means less variance. The less weight you use, the more stable you will be.

 

[Jeblis]

Probably not a good technique when the bottom is 6000 feet below.


(touching the bottom)