Where's your BC?

[crabbyjim]

You are right on all points Charlie. I didn’t mean to imply that less weight would be worn for a deep dive for the reasons you stated.  That’s why divers in old movies like Creature from the Black Lagoon the divers are resting on the bottom unless they are actively swimming. 

[nikeajax]

Curse you Phil for getting that song stuck in my head

JB

[SeaRat]

Feb 18, 2018 7:43:44 GMT -8 crabbyjim said:

Feb 17, 2018 22:59:18 GMT -8 SeaRat said:

From our discussions on Facebook, the problem isn't just the negative weight, but that with those fills, apparently to 4000 psig, there is an 8 pound swing in buoyancy. Because of this swing, I called the tank itself a buoyancy device, and that these divers needed to pay attention to three buoyancy devices, their tank's buoyancy, the dry suit, and their BCD. That makes for complicated diving. The reply was that their dry suit automatically vents when it is left-shoulder up, and it becomes second nature. But, in an emergency, when things go haywire, second nature goes out the window. I won't dive those high-capacity tanks.

John

John, you have hit the nail on the head, as usual, regarding the high capacity tanks.  I have two, 80 cf, 3440 tanks that are 8 lbs negative full and 2 lbs negative empty. After struggling with the buoyancy characteristics of these tanks,  I now use them to top off my other tanks.  As to the dry suit as primary buoyancy control, that is how it was taught 20 years ago and is still a good technique.  Trying to regulate buoyancy with 2 devices is twice as complicated as using the suit itself. Having said that, When diving with an integrated bc/backpack the bc becomes a redundant safety device for self rescue. 

Speaking of self rescue, in the text accompanying your Clear Lake picture, you mention wearing a life vest.  That's a redundant safety feature and I'm sure that's why you wore it.  When I learned diving in 1970 my zippered, U.S. Divers vest with an oral inflator and 16 g co2 cartridge was a safety device for a properly weighted diver. I was also taught that the weight belt wasn't worth your life and to ditch it in an emergency.  We made our own weights because we were safety conscious and cheap.

The person who spoke to Charlie was probably someone who learned to dive long after he first dove.  With modern bcd's, it is easier for an instructor to add lead than to get someone properly weighted for the intended dive profile.  Do they even teach that anymore?  

Lastly, none of this applies to "technical divers".  I dive "vintage style" whether I'm using a drysuit and bcd or wetsuit, weight belt, double hose regulator and horsecollar.  

CrabbyJim,

I won't comment on all you've written here, but will show a photo that is the last of the found photos that I recently scanned. This again comes from about 1973, and shows me with a new wet suit, custom made by Bill Herder at Deep Sea Bill's in Newport, Oregon. It features a BC built into the back of the wet suit, an inverted "U" of neoprene with an oral inflator. I am also wearing a vest, as I did not feel that back-mounted systems would keep me face-up if I was unconscious. I also have a full-face mask with the twin hoses of my Mistral regulator coming into it. Finally, I'm using a backpack with 16 pounds of weight, and a Hawaiian-style hooks instead of shoulder straps. This was when I was actively experimenting with different BC combinations, and the back-mounted system built into the wet suit was very, very streamlined as well as being very functional. Later, this was converted to the entire back of the wet suit being a BC.


This was probably a dive I made at Twin Bridges on the Siletz River, and I'm unsure of the date, although it could have been 2 June, 1974.

John

[vance]

Feb 18, 2018 15:05:22 GMT -8 nikeajax said:

Curse you Phil for getting that song stuck in my head

JB

Me too. Alternating with "California Uber Alles"

"We're the suede-denim secret police,
Comin' for your uncool niece!"


www.youtube.com/watch?v=GoA_zY6tqQw

[SeaRat]

Here is a rather long post I made on the Facebook page noted above:

I understand the commitment to diving with complete control of buoyancy, and the need to protect coral and keep off the bottom. But not all diving is like yours. Not all divers dive blue water. And not all divers dive where there is coral reefs to protect.

In diving, when I learned teaching from NAUI, we were taught to teach from the known to the related unknown. Unlike myself and many other very old-time divers who started scuba after being on swim teams and in lifeguard training, a lot of today's divers are basically landlubbers who have very little experience in and under the water. Everyone who is alive walks upright, and if not swimming throughout childhood, learns things upright. Being horizontal is foreign to their whole body perceptions. So in order to teach these people, you need to start upright and get them used to being horizontal. That takes time, and in order to get some similance of competency with scuba, they also need to clear masks, etc. This can be done most easily from the kneeling position.

Let's face it, being competent with buoyancy control is more than being horizontal and having your BC inflated correctly for the weight you are carrying. It also has to do with knowing you are neutrally buoyant at the surface (for me that is floating without air in the BC at eye level with a full breath in my lungs), and then compensating for weight as a wet suit is squeezed by the pressure of depth. That is what B.C. stands for, "buoyancy compensation," or compensating for that loss of buoyancy as depth increases.

I see some divers, and even instructors, who weight themselves purposely very heavy, and rely upon the BC to overcome their over-weighted condition, even in a pool or on the surface. If the BC somehow deflates, they have a real problem, and need to dump their weights in order to make it to the surface. I heard about a diving fatality in Clear Lake, Oregon in the 1970s that involved a diver jumping into the lake with an AtPak (a back-mounted BC system), and overweighted; unknowingly his LP inflator was not hooked up, and he was in over 90 feet of water. He did not make it.

If you are not wearing a wet suit, buoyancy compensation becomes less relevant. Below is a photo I took of dives I made in the U.S. Air Force off Okinawa in 1968, sans wet suit. We wore underarm life preservers folded into their pockets instead of a BC. BC's are irrelevant if you are not wearing a wet suit, and here the water was over 80 degrees F (~27 degrees C).
www.facebook.com/groups/1612046102342961/?multi_permalinks=1979426495604918&comment_id=2019072311640336¬if_id=1519035884602027¬if_t=feedback_reaction_generic&ref=notif

John

[crabbyjim]

Holy moly John,  Dene Ulmschneider at that FB page really didn't like what you had to say.  I'm certain that she wouldn't approve of old timey training problems like doffing and donning your gear.  We did that in the pool and in open water.  Was the inverted "u" in your custom wetsuit the subject of your patent application?

[nikeajax]

My wife and I went to the Tilden Botanic Garden in the Berkeley foothills today. When I hike I prefer to wear classic gear, a cotton-duck and wood-framed pack, wool, leather, etc. I like them for their simplicity and functionality. I was thinking about how much I like classic camping gear too, things you need to learn to use: things that require thought. I find new gear so boring because it's so over-engineered, it takes all of the romance out of doing something.

I then started contrasting that with my dive gear: I have very little interest in something I can't service myself, well, because I don't really trust it. Not always, but certainly most of the time, when something modern dies, it's pretty much toast: plastics and microchips make things lighter, but because they can do more, we are more dependent on them and the multifacetedness makes them much more susceptible to catastrophic failure.

I love the idea of simplicity in diving, and everything else: but what makes it safe is the knowledge it takes to know how to use it and what makes it work.

I don't think I'll ever know how many hours I've spent learning how scuba regulators work, but it is literally in the thousands. Unfortunately, the number of people who appreciate this knowledge-base is something like, ohhh, I d'know .00001% and the rest only view my gear as a health and safety hazard

JB

[cnotthoff]

Dang, didn't know I'd start so much controversy. I like the simple too. Probably, my favorite dive gear configuration is a wetsuit, weightbelt, fins, mask, and snorkel. Add an ab iron or speargun and I'm good to go. Guess I have to leave the ab iron at home this year.

Good Dives,
Charlie

[vance]

People on the internet do have their opinions. Good for them. I have mine, too. I'm sure there are people who disparage my point of view on some topics as much as I disparage theirs. If we don't agree, that's aight. SJW types and super-conservative types abound everywhere. And that can be both good and bad.

Interestingly, and I'm sure this is the case right here on this forum, people with all kina opposing beliefs can get along and become friends where there's a common interest (except when their belief is that vintage gear is dangerous ). And, hopefully, finding out that others are goodhearted and genuinely kind people who are worth knowing, we become a bit more willing to accept differing points of view. 

[Deleted]

You guys are becoming toooooo philosophical.........now, what is this about "where's your damn BC?"

[nikeajax]

Phil, I totally agree: there ain't never not jus' one way ta do sumthin! It's when people become dogmatic and refuse to listen to someone else’s views that things can get irritating to say the least: in other words, when people need to be right

JB

[duckbill]

Feb 19, 2018 16:28:05 GMT -8 cnotthoff said:

Guess I have to leave the ab iron at home this year.

Good Dives,
Charlie

Uh, oh! Why is that? What happened? (I'm not current on the regulations)

[crabbyjim]

Abalone is closed in 2018 to protect crashing populations. Read all about it here:

 cdfgnews.wordpress.com/2017/12/08/california-recreational-abalone-fishery-to-be-closed-in-2018/

[crabbyjim]

Feb 19, 2018 17:38:03 GMT -8 vance said:

People on the internet do have their opinions. Good for them. I have mine, too. I'm sure there are people who disparage my point of view on some topics as much as I disparage theirs. If we don't agree, that's aight. SJW types and super-conservative types abound everywhere. And that can be both good and bad.

Interestingly, and I'm sure this is the case right here on this forum, people with all kina opposing beliefs can get along and become friends where there's a common interest (except when their belief is that vintage gear is dangerous ). And, hopefully, finding out that others are goodhearted and genuinely kind people who are worth knowing, we become a bit more willing to accept differing points of view. 

Phil, the people who frequent this forum appear to be in agreement on most subjects and any disagreements are handled gently.  We all like scuba diving and vintage gear.  Many of us enjoy collecting and working on vintage gear.  Newcomers are graciously welcomed. We all enjoy each other's company. The only argument in this thread was imported by Searat from another forum where it is a mortal sin to touch the bottom of the ocean. Compared to other forums we're just a bunch of peace loving hippies.

Let's talk about some thing else.

[vance]

I agree with you. I understood the discussion, and was merely commenting on how things can get stupid crazy on the internet AND how I appreciate that this forum avoids this pitfall.