Any tips on valve drill

[TSandM]

I will gently disagree with Blackwood. If you have to close your right post in small, silty passage, it's not a big deal -- until you hit the silt and convert a simple problem to a zero-viz gas loss issue. Controlling your buoyancy within inches while doing shutdowns or air-sharing is a critical skill for cave diving. I don't know if that's what you eventually want to do, but if so, your concern is very reasonable.

For mask skills, the biggest thing is to remember that clearing your mask requires about 150 ccs of air. There is no need to take a full breath and blow like a leaf blower. A gentle trickle of air into the mask will eventually clear it, if the issue that caused the flood in the first place has been corrected. If you don't alter the pattern of your breathing to deal with the mask, your buoyancy won't change.

As far as buoyancy with mask off, open your eyes! Having even the dull blur of your buddies for orientation will help a TON. Obviously, this does not translate to lights-out in a cave, but there, you have the line for a proprioceptive reference (and in open water, if your buddy makes touch contact with you, as he ought, you have that, too).

Kudos to you for trying to get these things really RIGHT. I dove with a fellow whose cave instructor had told him, "Don't worry about your buoyancy and trim during shutdowns -- in a real situation, you'll silt the cave out, anyway." I don't believe that is true, and I don't believe that is a good way to teach. It is very hard work to get to where you can cope with whatever is thrown at you without any changes in buoyancy and trim, but it is work worth doing.

 

[Blackwood]

I will gently disagree with Blackwood. If you have to close your right post in small, silty passage, it's not a big deal -- until you hit the silt and convert a simple problem to a zero-viz gas loss issue. Controlling your buoyancy within inches while doing shutdowns or air-sharing is a critical skill for cave diving. I don't know if that's what you eventually want to do, but if so, your concern is very reasonable.

Note that I wasn't intending to suggest that he need not control his buoyancy.

What do you do when that passage lasts for 5 minutes? Do you alter your breathing such that you barely inhale or exhale about the middle point? Or do you breathe normally?

I suspect you breathe normally (I would), and that you don't rise and sink dramatically.

Same thing with a valve drill. As long as you don't fumble around getting the backup in, your normal breathing pattern shouldn't be interrupted.

 

[TSandM]

No, I'm only talking about the time it takes to breathe down the right post until the lines are empty. Obviously, you then switch to your backup reg and go back to breathing normally. I understood that the OP was having problems with ending up with empty lungs when the reg went dry, and then sinking as he changed regs. I had that problem at the beginning, and just learned not to have lungs that empty!

 

[kathydee]

I went through the same challenge recently, so perhaps I can offer a few tips that helped me.

Before you start the drill make sure you are in the middle of your buoyancy window.

The smoother, easier, more relaxed your reg switch is -- the less you tend to sink (even if you are on an out breath).

In the beginning I noticed some apprehension towards the last turn of the valve which caused challenges with buoyancy. So I just practiced the valve shut/ reg switch without thinking about other aspects of the drill till that feeling didn’t bother me anymore. It helped.

Also, make sure your head stays back and feet stay relaxed during the entire drill.

With practice it's become almost automatic .

 

[limeyx]

No, I'm only talking about the time it takes to breathe down the right post until the lines are empty. Obviously, you then switch to your backup reg and go back to breathing normally. I understood that the OP was having problems with ending up with empty lungs when the reg went dry, and then sinking as he changed regs. I had that problem at the beginning, and just learned not to have lungs that empty!

Or just switch to your backup, clip off the primary and then purge it down instead of breathing it (EDIT: For the small silty passage scenario, not the drill)

 

[WVMike]

I understood that the OP was having problems with ending up with empty lungs when the reg went dry, and then sinking as he changed regs. I had that problem at the beginning, and just learned not to have lungs that empty!

Yep, that was the issue. And thanks to the good tips and advice I got I will be correcting it. And, as you said, "learning not to have my lungs that empty". Thanks for eyes closed advice.

BTW, is that a Borg Cup Cake? It finally dawned on me

 

[WVMike]

I went through the same challenge recently, so perhaps I can offer a few tips that helped me.

Before you start the drill make sure you are in the middle of your buoyancy window.

The smoother, easier, more relaxed your reg switch is -- the less you tend to sink (even if you are on an out breath).

Also, make sure your head stays back and feet stay relaxed during the entire drill.

With practice it's become almost automatic .

Thanks for the tips. I will practice these. Now about the relaxed part. If you could offer some good advice on how to relax, that would help me 24/7.

 

[Blackwood]

Alprazolam - Wikipedia, the free encyclopedia

 

[elan]

Cannabis (drug) - Wikipedia, the free encyclopedia

 

[WVMike]

Alprazolam - Wikipedia, the free encyclopedia

Which begs the question, Is Alprazolam DIR ? :depressed: