Dive shops and training: the disconnect with reality

[BabyDuck]

jeff, have i told you lately that i love you? don't tell larry.

 

[JeffG]

jeff, have i told you lately that i love you? don't tell larry.

Its my secret.

 

[jbtut]

jtbut, in answer to your question about how much buoyancy a 7 mil suit can lose, the GUE guys played with one and came to the conclusion that a relatively new suit (that would, I assume, fit a typical male diver) can lose upwards of 20 lbs of lift at 100 feet. (The figure they gave was 23, for the suit they tested). This means that, if you are even neutral at the surface at the beginning of the dive (the most positive you should ever be) you could be 23 pounds negative a couple of minutes later, when you reach a hundred feet. 23 pounds is a lot to swim up. If you also add 7 pounds or so for a 100 cubic foot tank's worth of gas, you've got THIRTY pounds to swim up. Not very many people are going to be able to do that, although *dave* has a video of him swimming up 23.

It is very much worth regarding the possible loss of buoyancy from the compression of thick neoprene. Many divers here in the Sound, if they dive wet, dive with two layers of 7 mil on their torsos. They have a tremendous buoyancy loss at deeper depths. The lesson is, either have redundant lift or have significant ditchable weight. The problem with the latter as a bailout plan is that, when the neoprene rebounds, you will lose control of your ascent rate.

It is highly unlikely that you will tear both your wing and your suit to the point where you can't contain any gas in either (I suppose getting into wash rocks with mussels on them might do it!) More likely is a small puncture in one or the other, which would permit maintaining some gas in the proper attitude. Again, technical divers plan for the worst case, every dive; for recreational divers, I think it's worth looking at the potential for a bad outcome, and taking whatever precautions are reasonable.

Drysuits add up to a bunch of benefits in cold water, which outweigh their drag problems.

Thanks, Very interesting. That is a significant change in buoyancy. A std. 6' SMB has about 30lbs of lift, so that would just barely get you equal if you had a BCD issue a 7mm farmer john. A 10 footer might be worth while in that case. Of course you could dump a little weight rather than all of it, but you'd still be in an unstable equilibrium and once you rise you'd lose control.

It seems like a dry suit, if nothing else would be worth it for the comfort, although I never dive in cold water.

Do many/any tech divers use multiple bladder wings? That seems to be the general solution for other puncture prone air bladders like rafts etc.

 

[JeffG]

Do many/any tech divers use multiple bladder wings? That seems to be the general solution for other puncture prone air bladders like rafts etc.

Some do and others frown on that practice.

Standard behavior from the dive community.

 

[DA Aquamaster]

No need to thank me for the clarification, I know you wouldn't anyway

What an interesting thread.

Promoting retractors in the face of the informed opinions of cave divers takes a special kind of arrogance combined with supreme ignorance.

Personally, I've dove with Bob in places where you'd last about 5 minutes. I'd be happy to dive with Bob again. In contrast, at best, based on your internet conduct and apparent lack of knowledge, I'd be happy to take you some places I've been with Bob.

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Jeff G is absolutely correct about the reading comprehension thing. If you read Marci's post as well as his, it is obvious that Marci and Larry are involved, not Larry and Jeff. But of course having read numerous posts of yours in this thread as well as others, it is obvious the intent was to take a cheap shot at Jeff and in the process, probably through unintentional yet complete and total inconsideration of others, insult anyone who may choose to be in a same sex relationship.

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Oddly enough, it is divers like you that promote the current system of dive training, since the current system can clearly pump out self appointed recreational experts who think they know everything worth knowing about diving and lack the common sense, humility or self awareness to realize not only how much they have to learn, but also that they do not yet even know enough to know how little they really know.

A legitamate argument is whether the cheicken or the egg comes first. I''ll pick on PADI but the same applies to most recreatioal certification agencies. They developed and promoted quick and dirty training programs that will turn just about any non-diver into a *diver* in a weekend or two, all for the purpose of separating for their money for the course, the equipment and the touristy pretty fish trips they will take where they then have the opportunity to rototill the reef. What many new "divers" actually get from all this is not the diving but rather, an ego boost and the ability to *claim* they are actually a diver.

So does the current system attract people who buy into that BS or does it help create them?

What is clear however is that many shops also do not like the system, nor do many of the instructors in tropical destinations who are increasingly often being sent graduates of weekend dive courses who are seeking tropical check dives - yet are totally lacking in basic skills.

It is a system that is all about marketing and money rather than dive training and the sad part is that the agencies that started it are now buying into their own BS on the issue.

Other reasons why so many instructors and DMs suck can be found in the "going pro" forum, where you will often find a newly minted diver (usually a self appointed recreational expert) agonziing whether to become a DM or instructor now, or wait another 20 dives so they can double their "experience". That's a slightly different problem as the industry pays DMs and instructors peanuts, if it pays them at all - but the industry then gets exactly what it paid for.

Larry

 

[DaleC]

Thanks, Very interesting. That is a significant change in buoyancy. A std. 6' SMB has about 30lbs of lift, so that would just barely get you equal if you had a BCD issue a 7mm farmer john. A 10 footer might be worth while in that case. Of course you could dump a little weight rather than all of it, but you'd still be in an unstable equilibrium and once you rise you'd lose control.

It seems like a dry suit, if nothing else would be worth it for the comfort, although I never dive in cold water.

Do many/any tech divers use multiple bladder wings? That seems to be the general solution for other puncture prone air bladders like rafts etc.

Hi JB. I think that using a 10ft. SMB as a lift device would be awkward. In order to fill it with air you would give up the ability to manipulate the dump valve effectively on the way up. Most (at least the ones I know) divers up here opt for a lift bag in the 50# range (not a long SMB). This is folded up and stored behind the back or in some other out of the way but accessable spot.

As far as redundant bladders goes. I have no firm opinion on the issue other than that I opt not to have both bouyancy devices in an area where one action can damage both. I can see some mechanisms of injury scenarios where both bladders could be holed at once. I use a drysuit, BC and a 50# lift bag.

Some hardy souls do use wetsuits up here but, as Lynne states, they are in the minority. I admire their toughness but WS diving in coldwater has three downsides to me:

Suit compression means less insulation at depth. This is overcome by doubling up 7mm core layers (usually) which results in a lot of lead needed to overcome surface bouyancy.

Dive times are limited. I'm sure there are some who think they can dive the same profiles as a DS diver but they just haven't done a long dive yet. The invite is out to anyone in a 7mm semidry and a single Al 80 who thinks they can join me for a 90min+, 45F degree dive (within Rec NDL limits of course).

It's the second dive that gets you. Most divers can do the first <1hr dive in a WS even in 45F water but they usually begin to get chilled during the SI. After that they hit the second dive cold and hypothermia becomes a factor to consider. Try adding a third dive and you are pushing the limits (though it can and has been done).

Having said that, there's nothing wrong with diving a wetsuit in cold water. I plan on diving a single 7mm this summer (for easier profiles) to give my DS a rest from wear and tear.

 

[DaleC]

I'm still trying to figure out why my 1/2 BS but 1/2 on topic post was dropped by the mods but some other full BS posts remain? What does half the dribble from a certain poster add to any kind of diving knowledge?
Except as a precautionary tale.

 

[idocsteve]

What does half the dribble from a certain poster add to any kind of diving knowledge?
Except as a precautionary tale.

That might be enough. If you drop your weight belt, look behind you before you pick it up.

 

[Cave Diver]

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A ScubaBoard Staff Message...

Off topic chatter moved to a more appropriate place. As a reminder to all, this is in the Basic Scuba Forum. Special rules apply.

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[KeysCuda]

I know the "shop vs. online" thing has been debated endlessly, but I'll offer this:
When I buy a motorcycle helmet, I know the make and size I need. I buy online to a) save money; and b) get the color and exact model I want.
However, when my girlfriend bought her first helmet, we went into a cycle shop where a staffer measured her head, and spent time helping her try on different models. When she picked one out, I was more than happy to pay the shop's price.
I could have dashed home to order the exact same thing online, saving me money and giving her a wider choice of colors. But sometimes, you spend the money because it's the right thing to do.

OP:
Dive lights: Ha. Mine cost $18, from a Home Depot.
Manufacturer makes a "dive light," which is exactly same as mine, except for color - and price (higher, surprise).
Yes, in my local conditions (So Fla) always think: Streamline!