Question regarding neutral buoyancy

[inquis]

@napDiver I also think the "add another pound or two next time" approach is pretty effective once you're familiar with what the ascent should feel like and you're already close (for instance, holiday weight gain ). Breathing can compensate for being about 3-4 lbs light and probably 5-6 heavy.

 

[VikingDives]

@napDiver Breathing can compensate for being about 3-4 lbs light and probably 5-6 heavy.

 

[inquis]

Haha, at your gentle prompting, @VikingDives, I looked at the basis of my position. I'd have to revise it to [edit: breathing being able to compensate for being] 2-3 lb light. I think I'm still good on the heavy side, though. I await the arguments as to how I've gone astray...
Lung volumes - Wikipedia

 

[Blackcrusader]

Haha, at your gentle prompting, @VikingDives, I looked at the basis of my position. I'd have to revise it to 2-3 lb light. Still good on the heavy side, though. I await the arguments as to how I've gone astray...Lung volumes - Wikipedia

I prefer to dive with extra weight. I have seen divers head down finning to do a safety stop as they are underweighted for the end of the dive. I can just give them an extra kilo or two. Being able to become neutrally buoyant will not matter if you have a little too much weight than being perfect at the surface doing a weight test with 40 bar in your tank. You have a BCD so use it. As long as you are not underweighted in open water trying to do that 5m stop. Just my humble opinion.

 

[VikingDives]

Haha, at your gentle prompting, @VikingDives, I looked at the basis of my position. I'd have to revise it to 2-3 lb light. Still good on the heavy side, though. I await the arguments as to how I've gone astray...
Lung volumes - Wikipedia

I have a 8 pound range, thinking about it. It looks something like this:

-- (-2 lbs) I'm a little light and I'm not going to enjoy the safety stop.
-- (just right)
-- (+2) a little heavy, but I can donate if a student needs it
-- (+4) this sucks but I can still manage the dive. If you are +4 lbs/+2 kg you can drop like a rock...

I haven't hit the water at anything but just right since I became an instructor. I don't start students overweighted, so I don't have any major buoyancy issues. When I was a DM, I was rolling heavy, but the instructors I worked with were the "anchor them to their knees" types, and it wasn't unusual for DMs to invert and kick down chasing grossly over-weighted students.

I have been known to tell my DMs and AIs how easy they have it. They may have to occasionally chase a tense student to the surface, but it's nowhere near what I had to do... Proper weight of students and new divers is the holy grail.

OTOH, I appreciate DMs and folks like @BLACKCRUSADER who bring a little extra on dives. It's always nice to have a little extra flex on a first dive in a new environment.

 

[napDiver]

@napDiver I also think the "add another pound or two next time" approach is pretty effective once you're familiar with what the ascent should feel like and you're already close (for instance, holiday weight gain ). Breathing can compensate for being about 3-4 lbs light and probably 5-6 heavy.

I prefer to dive with extra weight. I have seen divers head down finning to do a safety stop as they are underweighted for the end of the dive. I can just give them an extra kilo or two. Being able to become neutrally buoyant will not matter if you have a little too much weight than being perfect at the surface doing a weight test with 40 bar in your tank. You have a BCD so use it. As long as you are not underweighted in open water trying to do that 5m stop. Just my humble opinion.

I agree with you both. If I'm unsure of weighting of myself or teammates or environmental depths or I know it will be shallow, I tend to bring an extra 2lbs on my tank cam band. If I'm diving just my GF and myself, my only extra weight I can pass to her is my flash lights and butt pouch. Funny I had to do this once, cause the new dive site was so shallow 7ft at the start and had a strong surge that pushed slight up she had issues until we could get to where the bottom was at least 13 ft. Although for you DMs and Instructors, I doubt I'd want to pass a big flashlight to a student that may break or drop it. This is why I told the new diver if your properly weighted you can add a couple lbs if you want, but I guess assuming any diver is correctly weighted is a bad assumption?

The biggest reason I have no issues being 2-4 lbs overweight is, I always have an SMB I can pull on for safety stops. It's much better to be slightly overweighted with a DSMB vs if your too underweighted.

The lung volume thing, I've never thought about or measured. I expect the -2lbs to 4 lbs would be comfy enough. I know when I have to do my safety stop upside down and kicking to maintain depth while keeping my lungs as empty as possible, It's probably the least comfortable thing other than an uncontrollable spinning ascent.

 

[scubaozy]

The fin pivot is a poor teaching tool in which a student is foot heavy and negatively buoyant. There is no reason to cling to antiquated methods when better methods are available. It just hampers new divers’ progress. Same is true for teaching on the knees.

Seasoned instructor would open their toolbox and use whatever tool it takes to get the job done. Every individual learns differently, every course is different. I try to extend my arsenal, not narrow.

If open water divers were taught properly, GUE fundies may never have been created.

You wrote that you were idc staff with 380 dives when you took gue fundies and perfected your buoyancy. That is not a lot of experience for even a DM. Could it be that real problem is that instructors buying their ways into the rankings, without sufficient experience?
Learning is an individual journey, mastery requires repetition and that takes time.

 

[wetb4igetinthewater]

Seasoned instructor would open their toolbox and use whatever tool it takes to get the job done. Every individual learns differently, every course is different. I try to extend my arsenal, not narrow.

I know you are being serious with your statement, but I did actually laugh as you brought back the memories of the worst open water class I taught. It was a class of 9, and I had another instructor assist. He said "I've been "teaching for decades." He told this to the students, not me. And he's the reason why it was the worst class I taught. Why? I was trying to teach the course neutral buoyancy and trim. I was giving students, him, and a DM all instructions to practice hovering while they waited their turn. As he was an instructor, I broke up the class in half as we had 6 hours of pool time.

And what did I see each time I turned around and looked to see how that half of the class was doing? They were either floating on the surface or sitting on the bottom. So I would signal them to hover. And as I found out later, he would tell them to sit on the bottom, not hover, or just float at the surface, as he "had been teaching for decades" and I had not.

So these dinosaurs need to do incoming students a favor. That favor is to stop teaching. They hardly ever add to their toolbox. They cling to past inferior methods. If instructors don't dramatically improve their teaching methods over time, they are worthless. Diving isn't rocket science which leads me to your next comment.

You wrote that you were idc staff with 380 dives when you took gue fundies and perfected your buoyancy. That is not a lot of experience for even a DM.

So, one of my OW/AOW students went on to take fundies and T1. He earned his T1 certification after 2 years, and 230 dives. Not a long time, not a lot of dives, is that? The time/dive count doesn't matter. The ONLY thing that matters is skills in the water. People get waaaaaaay too hung up on dive count. My former student will dive circles around most divers with THOUSANDS of dives. Give me a break.

Could it be that real problem is that instructors buying their ways into the rankings, without sufficient experience?

Are we buying it? Or are the standards so pathetically low in terms of skills set required? Maybe we are being suckered a bit too?

Learning is an individual journey, mastery requires repetition and that takes time.

Mastery requires a proper foundation. Give that foundation and the trajectory for mastery is much, much shorter.

 

[TMHeimer]

The main thing is you don't want to be at all underweighted if you'll be doing a safety stop. It's funny that we always talk about being properly weighted, then to add 5-6 pounds after a weight check to compensate for the tank getting continuously lighter. So, at the end of the dive you are properly weighted (well, maybe at some exact point somewhere).

 

[60plus]

Agree with posts that emphasise getting your weighting correct, it should be difficult, requiring a full exhale to initiate your descent. This minimises the amount of air you need in BCD. What I tend to do when I reach bottom and have to wait for others coming down line is to do a fin pivot and adjust my BCD to give neutral buoyancy with minimum load on the fin tips and my lungs about 1/2 to 5/8th full. Slightly inhale to rise from bottom and fin.