Cruise Ship Dive Excursions

I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of
weights for his next dive!<G> (or.......the kind that are made of cement and
you wear on your feet)
"Reef Fish" <Large_Nassau_Grouper@Yahoo.com> wrote in message
news:1124560967.637559.139990@g43g2000cwa.googlegr oups.com...
>
> Dan Bracuk wrote:
>> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his
>> keyboard resulting in:
>> :Anymore words of wisdom about diving, Dan?
>>
>> I did my first hundred dives in cold water and my last 400 or so in
>> warm.
>>
>> If you can dive in cold water, you can dive in warm. It is just so
>> much easier.
>
> It's easier, alright. Not MUCH easier, if you DO IT RIGHT (not DIR).
>
> If you learn your cold water diving from the Bozos like Dave Waller
> and Nick Simicich, as I documented in my preceding posts in reply to
> you, then you would have been an incompetent diver, in Warm OR Cold
> water.
>
> I did my ICE diver cert in 1990. Can't get much colder than that.
> Because I was WARM water trained and was already an experienced
> WARM water diver, I had no trouble at all diving in drysuits,
> except the neck seals of the rental suit choked me (because it
> was 4" smaller than my neck seal should be. So, I did my
> ice dives in my 1/4" wetsuit.
>
> BUOYANCY control is EVERYTHING in diving -- except it's a skill
> seldom acquired by the Cold-Water trained divers.
>
> The FIRST thing the ice diving instructor did in the pool session
> (on drysuit training) was to give me 30 lbs of lead after a quick
> look at me. I did a quick look at him, and handed back 15 of
> the 30 lbs. The 15 lbs was STILL too much lead, diving in that
> Viking drysuit.
>
> I had personally RESCUED some cold water trained divers in Cozumel
> (when they were sinking FAST) at 100 fsw and the DM was too far
> away tending to other clueless cold water divers. That one was
> only 20 lbs overweighted (in lead). The record I've seen was a
> New Joisey diver, who brought his own VEST (because no BELT could
> carry so much weight) and dived with 75 lbs of weight -- in his
> 1/4" wetsuit, in Cozumel.
>
> When you're 10 lbs over-weighted, you are 15 lbs too heavy on
> decent because of the 5+ lbs of AIR in the full tank!
>
> So, you would have to pump air in the BC to compensate for the
> 15 lbs of overweight. Do a little Boyles Law stuff and you'll
> see why so many cold water diver shoot to the surface when they
> forget to lease air (or not release enough air) from their BC
> on ascent.
>
> In short, an inexperienced, cold water trained diver is much
> more dangerous (to THEMSELVES as well to his diving environment)
> than an inexperienced warm water diver -- because the latter
> is seldom as OVERWEIGHTED (in lead) as the former.
>
> Short Pop Quiz:
>
> How many Cold Water diver you know calibrate their "proper weight"
> (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How
> many of them even KNOW what their proper amount of lead SHOULD be?
>
> -- Bob.
>

Dick wrote:
> I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of
> weights for his next dive!<G> (or.......the kind that are made of cement and
> you wear on your feet)

No need. I have over 100 lbs of lead picked up in Cozumel alone,
dropped
by divers like yourself, after I started giving what I picked up to the
boat captains.

I had found belts below 150 fsw that were too heavy for me to bring up
because my BC had a MAXIMUM lift of 16 lbs, fully inflated (they don't
make them anymore because it's too dangerous for divers like Dick).
Other
times I took the weights off the belt and distributed them for others
to
bring up.

Dick,

you have the gall to be a smartass -- who claimed to have dived for
20 years without any certification and then claimed to be an
"experienced"
diver when you had absolutely ZERO experience diving in warm water.

You're the biggest hazard to yourself, the warm water environment, and
the other divers who have the misfortune to dive with you.

-- Bob.



> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> wrote in message
> news:1124560967.637559.139990@g43g2000cwa.googlegr oups.com...
> >
> > Dan Bracuk wrote:
> >> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his
> >> keyboard resulting in:
> >> :Anymore words of wisdom about diving, Dan?
> >>
> >> I did my first hundred dives in cold water and my last 400 or so in
> >> warm.
> >>
> >> If you can dive in cold water, you can dive in warm. It is just so
> >> much easier.
> >
> > It's easier, alright. Not MUCH easier, if you DO IT RIGHT (not DIR).
> >
> > If you learn your cold water diving from the Bozos like Dave Waller
> > and Nick Simicich, as I documented in my preceding posts in reply to
> > you, then you would have been an incompetent diver, in Warm OR Cold
> > water.
> >
> > I did my ICE diver cert in 1990. Can't get much colder than that.
> > Because I was WARM water trained and was already an experienced
> > WARM water diver, I had no trouble at all diving in drysuits,
> > except the neck seals of the rental suit choked me (because it
> > was 4" smaller than my neck seal should be. So, I did my
> > ice dives in my 1/4" wetsuit.
> >
> > BUOYANCY control is EVERYTHING in diving -- except it's a skill
> > seldom acquired by the Cold-Water trained divers.
> >
> > The FIRST thing the ice diving instructor did in the pool session
> > (on drysuit training) was to give me 30 lbs of lead after a quick
> > look at me. I did a quick look at him, and handed back 15 of
> > the 30 lbs. The 15 lbs was STILL too much lead, diving in that
> > Viking drysuit.
> >
> > I had personally RESCUED some cold water trained divers in Cozumel
> > (when they were sinking FAST) at 100 fsw and the DM was too far
> > away tending to other clueless cold water divers. That one was
> > only 20 lbs overweighted (in lead). The record I've seen was a
> > New Joisey diver, who brought his own VEST (because no BELT could
> > carry so much weight) and dived with 75 lbs of weight -- in his
> > 1/4" wetsuit, in Cozumel.
> >
> > When you're 10 lbs over-weighted, you are 15 lbs too heavy on
> > decent because of the 5+ lbs of AIR in the full tank!
> >
> > So, you would have to pump air in the BC to compensate for the
> > 15 lbs of overweight. Do a little Boyles Law stuff and you'll
> > see why so many cold water diver shoot to the surface when they
> > forget to lease air (or not release enough air) from their BC
> > on ascent.
> >
> > In short, an inexperienced, cold water trained diver is much
> > more dangerous (to THEMSELVES as well to his diving environment)
> > than an inexperienced warm water diver -- because the latter
> > is seldom as OVERWEIGHTED (in lead) as the former.
> >
> > Short Pop Quiz:
> >
> > How many Cold Water diver you know calibrate their "proper weight"
> > (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How
> > many of them even KNOW what their proper amount of lead SHOULD be?
> >
> > -- Bob.
> >

Did we forget to take our medications again Bob?


"Reef Fish" <Large_Nassau_Grouper@Yahoo.com> wrote in message
news:1124632599.343412.24150@f14g2000cwb.googlegro ups.com...
>
> Dick wrote:
>> I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of
>> weights for his next dive!<G> (or.......the kind that are made of cement
>> and
>> you wear on your feet)
>
> No need. I have over 100 lbs of lead picked up in Cozumel alone,
> dropped
> by divers like yourself, after I started giving what I picked up to the
> boat captains.
>
> I had found belts below 150 fsw that were too heavy for me to bring up
> because my BC had a MAXIMUM lift of 16 lbs, fully inflated (they don't
> make them anymore because it's too dangerous for divers like Dick).
> Other
> times I took the weights off the belt and distributed them for others
> to
> bring up.
>
> Dick,
>
> you have the gall to be a smartass -- who claimed to have dived for
> 20 years without any certification and then claimed to be an
> "experienced"
> diver when you had absolutely ZERO experience diving in warm water.
>
> You're the biggest hazard to yourself, the warm water environment, and
> the other divers who have the misfortune to dive with you.
>
> -- Bob.
>
>
>
>> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> wrote in message
>> news:1124560967.637559.139990@g43g2000cwa.googlegr oups.com...
>> >
>> > Dan Bracuk wrote:
>> >> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his
>> >> keyboard resulting in:
>> >> :Anymore words of wisdom about diving, Dan?
>> >>
>> >> I did my first hundred dives in cold water and my last 400 or so in
>> >> warm.
>> >>
>> >> If you can dive in cold water, you can dive in warm. It is just so
>> >> much easier.
>> >
>> > It's easier, alright. Not MUCH easier, if you DO IT RIGHT (not DIR).
>> >
>> > If you learn your cold water diving from the Bozos like Dave Waller
>> > and Nick Simicich, as I documented in my preceding posts in reply to
>> > you, then you would have been an incompetent diver, in Warm OR Cold
>> > water.
>> >
>> > I did my ICE diver cert in 1990. Can't get much colder than that.
>> > Because I was WARM water trained and was already an experienced
>> > WARM water diver, I had no trouble at all diving in drysuits,
>> > except the neck seals of the rental suit choked me (because it
>> > was 4" smaller than my neck seal should be. So, I did my
>> > ice dives in my 1/4" wetsuit.
>> >
>> > BUOYANCY control is EVERYTHING in diving -- except it's a skill
>> > seldom acquired by the Cold-Water trained divers.
>> >
>> > The FIRST thing the ice diving instructor did in the pool session
>> > (on drysuit training) was to give me 30 lbs of lead after a quick
>> > look at me. I did a quick look at him, and handed back 15 of
>> > the 30 lbs. The 15 lbs was STILL too much lead, diving in that
>> > Viking drysuit.
>> >
>> > I had personally RESCUED some cold water trained divers in Cozumel
>> > (when they were sinking FAST) at 100 fsw and the DM was too far
>> > away tending to other clueless cold water divers. That one was
>> > only 20 lbs overweighted (in lead). The record I've seen was a
>> > New Joisey diver, who brought his own VEST (because no BELT could
>> > carry so much weight) and dived with 75 lbs of weight -- in his
>> > 1/4" wetsuit, in Cozumel.
>> >
>> > When you're 10 lbs over-weighted, you are 15 lbs too heavy on
>> > decent because of the 5+ lbs of AIR in the full tank!
>> >
>> > So, you would have to pump air in the BC to compensate for the
>> > 15 lbs of overweight. Do a little Boyles Law stuff and you'll
>> > see why so many cold water diver shoot to the surface when they
>> > forget to lease air (or not release enough air) from their BC
>> > on ascent.
>> >
>> > In short, an inexperienced, cold water trained diver is much
>> > more dangerous (to THEMSELVES as well to his diving environment)
>> > than an inexperienced warm water diver -- because the latter
>> > is seldom as OVERWEIGHTED (in lead) as the former.
>> >
>> > Short Pop Quiz:
>> >
>> > How many Cold Water diver you know calibrate their "proper weight"
>> > (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How
>> > many of them even KNOW what their proper amount of lead SHOULD be?
>> >
>> > -- Bob.
>> >
>

Dick wrote:
> Did we forget to take our medications again Bob?

Dickhead,

Are you talking about yourself in your editorial "we"?

Try something original, or at least lines that have not been used
by Clueless Newbies like yourself a thousand times, to everyone who
exposed their cluelessness.

-- Bob.
>
>
> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> wrote in message
> news:1124632599.343412.24150@f14g2000cwb.googlegro ups.com...
> >
> > Dick wrote:
> >> I have an idea!! Why don't we all chip in & buy Bob (Reef Fish) allot of
> >> weights for his next dive!<G> (or.......the kind that are made of cement
> >> and
> >> you wear on your feet)
> >
> > No need. I have over 100 lbs of lead picked up in Cozumel alone,
> > dropped
> > by divers like yourself, after I started giving what I picked up to the
> > boat captains.
> >
> > I had found belts below 150 fsw that were too heavy for me to bring up
> > because my BC had a MAXIMUM lift of 16 lbs, fully inflated (they don't
> > make them anymore because it's too dangerous for divers like Dick).
> > Other
> > times I took the weights off the belt and distributed them for others
> > to
> > bring up.
> >
> > Dick,
> >
> > you have the gall to be a smartass -- who claimed to have dived for
> > 20 years without any certification and then claimed to be an
> > "experienced"
> > diver when you had absolutely ZERO experience diving in warm water.
> >
> > You're the biggest hazard to yourself, the warm water environment, and
> > the other divers who have the misfortune to dive with you.
> >
> > -- Bob.
> >
> >
> >
> >> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> wrote in message
> >> news:1124560967.637559.139990@g43g2000cwa.googlegr oups.com...
> >> >
> >> > Dan Bracuk wrote:
> >> >> "Reef Fish" <Large_Nassau_Grouper@Yahoo.com> pounded away at his
> >> >> keyboard resulting in:
> >> >> :Anymore words of wisdom about diving, Dan?
> >> >>
> >> >> I did my first hundred dives in cold water and my last 400 or so in
> >> >> warm.
> >> >>
> >> >> If you can dive in cold water, you can dive in warm. It is just so
> >> >> much easier.
> >> >
> >> > It's easier, alright. Not MUCH easier, if you DO IT RIGHT (not DIR).
> >> >
> >> > If you learn your cold water diving from the Bozos like Dave Waller
> >> > and Nick Simicich, as I documented in my preceding posts in reply to
> >> > you, then you would have been an incompetent diver, in Warm OR Cold
> >> > water.
> >> >
> >> > I did my ICE diver cert in 1990. Can't get much colder than that.
> >> > Because I was WARM water trained and was already an experienced
> >> > WARM water diver, I had no trouble at all diving in drysuits,
> >> > except the neck seals of the rental suit choked me (because it
> >> > was 4" smaller than my neck seal should be. So, I did my
> >> > ice dives in my 1/4" wetsuit.
> >> >
> >> > BUOYANCY control is EVERYTHING in diving -- except it's a skill
> >> > seldom acquired by the Cold-Water trained divers.
> >> >
> >> > The FIRST thing the ice diving instructor did in the pool session
> >> > (on drysuit training) was to give me 30 lbs of lead after a quick
> >> > look at me. I did a quick look at him, and handed back 15 of
> >> > the 30 lbs. The 15 lbs was STILL too much lead, diving in that
> >> > Viking drysuit.
> >> >
> >> > I had personally RESCUED some cold water trained divers in Cozumel
> >> > (when they were sinking FAST) at 100 fsw and the DM was too far
> >> > away tending to other clueless cold water divers. That one was
> >> > only 20 lbs overweighted (in lead). The record I've seen was a
> >> > New Joisey diver, who brought his own VEST (because no BELT could
> >> > carry so much weight) and dived with 75 lbs of weight -- in his
> >> > 1/4" wetsuit, in Cozumel.
> >> >
> >> > When you're 10 lbs over-weighted, you are 15 lbs too heavy on
> >> > decent because of the 5+ lbs of AIR in the full tank!
> >> >
> >> > So, you would have to pump air in the BC to compensate for the
> >> > 15 lbs of overweight. Do a little Boyles Law stuff and you'll
> >> > see why so many cold water diver shoot to the surface when they
> >> > forget to lease air (or not release enough air) from their BC
> >> > on ascent.
> >> >
> >> > In short, an inexperienced, cold water trained diver is much
> >> > more dangerous (to THEMSELVES as well to his diving environment)
> >> > than an inexperienced warm water diver -- because the latter
> >> > is seldom as OVERWEIGHTED (in lead) as the former.
> >> >
> >> > Short Pop Quiz:
> >> >
> >> > How many Cold Water diver you know calibrate their "proper weight"
> >> > (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How
> >> > many of them even KNOW what their proper amount of lead SHOULD be?
> >> >
> >> > -- Bob.
> >> >
> >

Reef Fish wrote:

> BUOYANCY control is EVERYTHING in diving -- except it's a skill
> seldom acquired by the Cold-Water trained divers.

(Gently picking up the bait, feeling for any hook or line...)

I beg to differ, Bob.

Although most of my 769 dives didn't usually involve a buddy, I've
observed dozens of different coldwater divers on numerous occasions,
and they exhibited excellent buoyancy control, with the only exceptions
being three or four divers who repeatedly don't or won't.

All the others maintained neutral buoyancy quite well. They could
suspend without any significant movement. They swam effortlessly
without contacting the bottom or disturbing the bottom with jets of
downward thrust. They didn't scull with their hands. They didn't hover
like a vertical helo. They didn't drop down on the substrate unaware.
They didn't float toward the surface out of control. They didn't have
to constantly add and exhaust air to maintain buoyancy, so I assume
they weighted themselves close to the optimum.

> The FIRST thing the ice diving instructor did in the pool session
> (on drysuit training) was to give me 30 lbs of lead after a quick
> look at me. I did a quick look at him, and handed back 15 of
> the 30 lbs. The 15 lbs was STILL too much lead, diving in that
> Viking drysuit.

15 lbs is a remarkably low amount of lead, especially for a drysuit
worn by an averaged size male, even with a very thin undergarment,
assuming a typical single 80 aluminum tank.

However, it may have seemed "STILL too much lead", as you said, if your
pool dive didn't drain the tank much or if the undergarment was very
thin. I've seen some of the old Viking undergarments and they are
pretty thin. More suitable for above 50F active dives.

In cold water, I certainly wouldn't have been warm enough in that thin
an undergarment.

I have a quick rule of thumb for ROUGHLY estimating weighting required
by undergarments is to put them in a plastic bag and ball them up with
a little compression and estimate the volume they will displace in the
water.

An undergarment that fits in a 2-gallon container might be a little
thin for ice diving and alone may require 16 pounds to neutralize its
buoyancy.

Of course, in-water adjustment of weighting would be the last word.

The real last word will be thermal loss and shaking chills with an
inadequate undergarment or not enough weight to promote loft on the
uppermost areas of the undergarment when horizontal.

> How many Cold Water diver you know calibrate their "proper weight"
> (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How
> many of them even KNOW what their proper amount of lead SHOULD be?

Most, from what I've seen, get it pretty close, perhaps within 2 lbs of
the absolute minimum, but more likely a little further off. Very few of
us are concerned about how little weight somebody else has on or if
they've optimized their weighting.

With a drysuit, which I use all year, proper amount of lead for me
varies, as I'll change the amount of my insulation to match temp and
activity level, even between dives sometimes. I might even add a couple
lbs if my undergarments are a little damp from perspiration from the
first dive, which might have made the end of the first dive a little
chilly. Adding that little bit of extra weight can make the difference
in warmth for the next dive. Of course, the trade-off is slightly more
wasted air from adjusting for buoyancy changes during the dive.

I make the weighting adjustments from experience of trial and error,
occasionally referring to a log of what worked well to keep me warm
with various combinations of undergarments, hoods, gloves, etc. I don't
strive to get the optimum weighting for it's own sake because, frankly,
with a drysuit, it's not as warm.

Purists like to wear an abolute minimum of weight, but, in my drysuit,
I find I'm warmer with about 4 extra pounds. I think that achieves
better loft in the uppermost areas of the insulation when horizontal.
The trade-off is a little more air wasted when adjusting for changes in
buoyancy. Sure is nice to be warm as toast, though.

With a wetsuit, in shallow water, the purists' absolute minimum may be
more beneficial to reduce such waste of air, but that benefit is
reduced at depths where suit compression requires more air to maintain
neutral buoyancy.

I think the purists' love of minimal weighting is best justified in
warm water conditions which require minimimal thermal protection. Then
the positive benefits would be pretty consistent.

Dave C

Dave C wrote:
> Reef Fish wrote:
>
> > BUOYANCY control is EVERYTHING in diving -- except it's a skill
> > seldom acquired by the Cold-Water trained divers.
>
> (Gently picking up the bait, feeling for any hook or line...)

Hi Dave. It's no bait. Serious stuff!
>
> I beg to differ, Bob.
>
> Although most of my 769 dives didn't usually involve a buddy, I've
> observed dozens of different coldwater divers on numerous occasions,
> and they exhibited excellent buoyancy control, with the only exceptions
> being three or four divers who repeatedly don't or won't.

You've observed only dozens of divers? No wonder.

I've observed HUNDREDSs of cold water and warm water divers in
Cozumel on my first 100 dives there. I stopped counting my
Cozumel dives after THAT total reached 1200 several years ago.

>
> All the others maintained neutral buoyancy quite well. They could
> suspend without any significant movement. They swam effortlessly
> without contacting the bottom or disturbing the bottom with jets of
> downward thrust. They didn't scull with their hands. They didn't hover
> like a vertical helo. They didn't drop down on the substrate unaware.
> They didn't float toward the surface out of control. They didn't have
> to constantly add and exhaust air to maintain buoyancy, so I assume
> they weighted themselves close to the optimum.

Everything you said is quite plausible on what YOU observed. But
your last line is patently false!

A diver can be overweighted by 20 lbs and still exhibit what you
saw, in cold OR warm water diving. *I* can't dive even 10 lbs
overweighted. But most DMs in Cozumel can dive with 20 or 30 lbs
extra (to carry lead that might be needed by divers OR pick up
a dropped weightbelt) and still exhibit good buoyancy control.

But that's divers in the OTHER extreme. That they can dive in
spite of improper weighting.

Proper weighting can ONLY be calibrated, carefully, IN WATER, by
a diver who knows HOW.
>
> > The FIRST thing the ice diving instructor did in the pool session
> > (on drysuit training) was to give me 30 lbs of lead after a quick
> > look at me. I did a quick look at him, and handed back 15 of
> > the 30 lbs. The 15 lbs was STILL too much lead, diving in that
> > Viking drysuit.
>
> 15 lbs is a remarkably low amount of lead, especially for a drysuit
> worn by an averaged size male, even with a very thin undergarment,
> assuming a typical single 80 aluminum tank.

At that time I was diving with 6 lbs in warm water. I weighed 190 lbs
and wore a spare tire for natural insulation. It was in a pool,
hence no undergarment needed. The Viking suit itself has no buoyancy
except for the air in it. A typical single 80AL has 5+ lbs of weight
in its AIR over neutral. Thus, when I started with 15 lbs of lead,
it was 20 lbs above neutral. I could have easily dived with 10 lbs
of lead in that drysuit.

>
> However, it may have seemed "STILL too much lead", as you said, if your
> pool dive didn't drain the tank much or if the undergarment was very
> thin. I've seen some of the old Viking undergarments and they are
> pretty thin. More suitable for above 50F active dives.

True. The thinsulate undergarb (what was used in actual ice dives)
would have required another 10 lbs of lead or so. I had already
factored the air in the tank into the lead I needed.
>
> In cold water, I certainly wouldn't have been warm enough in that thin
> an undergarment.
>
> I have a quick rule of thumb for ROUGHLY estimating weighting required
> by undergarments is to put them in a plastic bag and ball them up with
> a little compression and estimate the volume they will displace in the
> water.

That's a very bad "rule of thumb". That's not even proper physics!
Proper calibration is no different for cold and warm water divers.
Find out how much ACTUAL weight you'll need to remain neutral (with
All air out of the BC) when you're doing your safety stop at 15 fsw
with 500 psi.

The most lead you need is the descent of the first 15 feet.
Thereafter,
no matter how thick your wetsuit is, it'll be compressed so much that
you'll no longer need the "proper weight" -- which is why a heavy
wetsuit wearer will need to pump a LOT of air into the BCD to
compensate for the wetsuit compression at 100 feet, say!
>
> An undergarment that fits in a 2-gallon container might be a little
> thin for ice diving and alone may require 16 pounds to neutralize its
> buoyancy.
>
> Of course, in-water adjustment of weighting would be the last word.
>
> The real last word will be thermal loss and shaking chills with an
> inadequate undergarment or not enough weight to promote loft on the
> uppermost areas of the undergarment when horizontal.
>
> > How many Cold Water diver you know calibrate their "proper weight"
> > (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How
> > many of them even KNOW what their proper amount of lead SHOULD be?
>
> Most, from what I've seen, get it pretty close, perhaps within 2 lbs of
> the absolute minimum, but more likely a little further off.

See, you're guessing, even for YOURSELF, judging from what you said
about how you estimate your own needed lead.

> Very few of
> us are concerned about how little weight somebody else has on or if
> they've optimized their weighting.

Or their own.

That's where WARM WATER WIMPS are much more "proper weight" oriented
because of the ease and freedom to DIVE WELL, without all the cold
water gear and needed extra weight!

Ultra trim trim plus minimal and proper weighting improves AIR
CONSUMPTION EFFICIENCY. That is one reason I can dive longer on
one tank of air than most.

I was so fined tuned that I could tell the difference in the salinity
of the water between the Atlantic (Bahamas) and the Caribbean!
I have custom-made 1/4 lb pieces of lead that inserts into my
weightbelt. Of course I had many 1 lb pieces too.

I think a diver SHOULD be properly calibrated to within a couple of
lbs. of the "proper weight". Most divers DON'T KNOW what that
number is, period -- or how to calibrate it!


> With a drysuit, which I use all year, proper amount of lead for me
> varies, as I'll change the amount of my insulation to match temp and
> activity level, even between dives sometimes. I might even add a couple
> lbs if my undergarments are a little damp from perspiration from the
> first dive, which might have made the end of the first dive a little
> chilly. Adding that little bit of extra weight can make the difference
> in warmth for the next dive. Of course, the trade-off is slightly more
> wasted air from adjusting for buoyancy changes during the dive.

I never quibble about any "couple of pounds" by anyone. It's the
UNNEEDED 5, 10, or 20 lbs that are so commonly practiced by cold water
divers that I crusade against.

>
> I make the weighting adjustments from experience of trial and error,
> occasionally referring to a log of what worked well to keep me warm
> with various combinations of undergarments, hoods, gloves, etc. I don't
> strive to get the optimum weighting for it's own sake because, frankly,
> with a drysuit, it's not as warm.

Proper weighting INCLUDES the consideration of proper (or chosen)
warmth
factor by the diver. So, if you needed 4 extra lbs for being WARMER,
it's no different from someone wearing 7 mil instead of 5 mil (ro my
3 mil) to be sufficiently warm.

BUt within EACH equipment (which includes the thickness of suit or
the amount of insulation) there IS a "proper weight" that CAN be
properly calibrated.

It's the inadquacy of TRAINING agencies, which produced poorly trained
Instructors, who in turn mis-taught proper weighting and buoyancy
control, such as Nick Simicich and Dave Waller (the two I had used
as examples) that led to students who pay no attention to over-
weighting.

It's that vicious cycle that needs to be corrected.

>
> Purists like to wear an abolute minimum of weight, but, in my drysuit,
> I find I'm warmer with about 4 extra pounds. I think that achieves
> better loft in the uppermost areas of the insulation when horizontal.
> The trade-off is a little more air wasted when adjusting for changes in
> buoyancy. Sure is nice to be warm as toast, though.
>
> With a wetsuit, in shallow water, the purists' absolute minimum may be
> more beneficial to reduce such waste of air, but that benefit is
> reduced at depths where suit compression requires more air to maintain
> neutral buoyancy.

You used the term "purist" rather improperly, if I may say so. I
don't mind being called a "purist" if you don't attach all the
untrue and derogatory implications in what you wrote!

My LYCRA suit has NO COMPRESSION whether I am at 15 fsw or 199 fsw
where I frequently visit. :) My 1.5 mil titanium was adequate
even for my dives in Bali where I dived comfortably in 65-70F
enjoying nearly 45 minutes of the one and only mola mola I've ever
seen.

The needed AIR in the BC is mostly to compensate for the 5 lbs
of extra weight of the AIR in the tank at the beginning of the dive!

>
> I think the purists' love of minimal weighting is best justified in
> warm water conditions which require minimimal thermal protection. Then
> the positive benefits would be pretty consistent.
>
> Dave C

It's perfectly justified in diving with any equipment, in any cold
water,
at any temperature -- but you have to KNOW how to calibrate your
minimum
and calibrate it properly.

That's the bottom line.

-- Bob,

Reef Fish wrote:
> Dave C wrote:
> > Reef Fish wrote:
> >
> > > BUOYANCY control is EVERYTHING in diving -- except it's a skill
> > > seldom acquired by the Cold-Water trained divers.
Snip
> > I beg to differ, Bob.
> >
> > Although most of my 769 dives didn't usually involve a buddy, I've
> > observed dozens of different coldwater divers on numerous occasions,
> > and they exhibited excellent buoyancy control, with the only exceptions
> > being three or four divers who repeatedly don't or won't.
>
> You've observed only dozens of divers? No wonder.

Just trying to provide objective information.

We're talking about two different things, though. Cold water divers in
their element versus in a tropical setting. I took exception to your
broad brush about cold water divers.

In a tropical setting, maybe you're right that they're cocky or
clueless and can't adjust their weighting. Just for the record, in my
limited tropical experience, I readily adjusted to having 8 lbs or
whatever it was with that 3mm shorty. 8^)

> I've observed HUNDREDSs of cold water and warm water divers in
> Cozumel on my first 100 dives there. I stopped counting my
> Cozumel dives after THAT total reached 1200 several years ago.

Since I'm observing these cold water divers in their element, perhaps
I'm seeing more profiicient divers than the ones who hail from "cold
water", but are on their warm water vacation. No doubt, being able to
readjust weighting for tropical conditions and gear is the real issue,
not the proficiency back home.

> > All the others maintained neutral buoyancy quite well. SNIP They didn't have
> > to constantly add and exhaust air to maintain buoyancy, so I assume
> > they weighted themselves close to the optimum.
>
> Everything you said is quite plausible on what YOU observed. But
> your last line is patently false!

I should have specified I was thinking of our typical sawtooth profile
where the overweighted diver will be intermittently purging copious
amounts of air. That gets pretty obvious. As is the amount of inflation
in the bcd.

> A diver can be overweighted by 20 lbs and still exhibit what you
> saw, in cold OR warm water diving. *I* can't dive even 10 lbs
> overweighted. But most DMs in Cozumel can dive with 20 or 30 lbs
> extra (to carry lead that might be needed by divers OR pick up
> a dropped weightbelt) and still exhibit good buoyancy control.
>
> But that's divers in the OTHER extreme. That they can dive in
> spite of improper weighting.

If they changed depths significantly, you'd see their significant bcd
adjustments, though, as they tried to maintain neutral.

> Proper weighting can ONLY be calibrated, carefully, IN WATER, by
> a diver who knows HOW.

We're in agreement here, but I'm suggesting the optimum weighting isn't
all that important. Wasted air is the primary issue. Being able to
react quickly enough with breath control or power inflator is the other
issue. 5 lbs excess weight shouldn't even present much of a problem
except in shallow water for less experienced divers.

So, maybe the real point is that optimal weighting makes it easier for
newbies to maintain buoyancy. Experienced divers can adjust to
overweighting better.

> > > The FIRST thing the ice diving instructor did in the pool session
> > > (on drysuit training) was to give me 30 lbs of lead after a quick
> > > look at me. I did a quick look at him, and handed back 15 of
> > > the 30 lbs. The 15 lbs was STILL too much lead, diving in that
> > > Viking drysuit.

I didn't think that the instructor would run you through the drill of
feet first out-of-control ascent without an undergarment to make it
more realistic. I'll bet the extra weight he suggested was to have the
excess, expanding air in the suit require more effort to fin down and
vent, either through somersault or push off the bottom maneuvers. That
might have been his intent.

By allowing you such little air in your suit, since you had no
substantial undergarment and had reduced your weighting, that made it
quite a bit easier, right?

> > 15 lbs is a remarkably low amount of lead, especially for a drysuit
> > worn by an averaged size male, even with a very thin undergarment,
> > assuming a typical single 80 aluminum tank.
>
> At that time I was diving with 6 lbs in warm water. I weighed 190 lbs
> and wore a spare tire for natural insulation. It was in a pool,
> hence no undergarment needed. The Viking suit itself has no buoyancy
> except for the air in it. A typical single 80AL has 5+ lbs of weight
> in its AIR over neutral. Thus, when I started with 15 lbs of lead,
> it was 20 lbs above neutral. I could have easily dived with 10 lbs
> of lead in that drysuit.

That all makes sense. Again, an undergarment would have been useful in
simulating the feet-first out of control ascent and recovery because it
would have provided more air and trapped the expanding air.

> > I have a quick rule of thumb for ROUGHLY estimating weighting required
> > by undergarments is to put them in a plastic bag and ball them up with
> > a little compression and estimate the volume they will displace in the
> > water.
>
> That's a very bad "rule of thumb". That's not even proper physics!
> Proper calibration is no different for cold and warm water divers.
> Find out how much ACTUAL weight you'll need to remain neutral (with
> All air out of the BC) when you're doing your safety stop at 15 fsw
> with 500 psi.

"ROUGHLY" estimating the weight required to neutralize buoyancy of some
unfamiliar combination of undergarments can be very useful and time
saving and get you within a few pounds of a good weight right off. The
final fine-tuning can then be done quickly in-water. I didn't mean to
imply that it's a primary on-going weighting adjustment method.

Again, this rule of thumb is for drysuit undergarments and works well
in practice. This past winter I added some folded pads of fleece over
my chest area and simply took the material, folded and balled it up and
estimated its displacement would be about a half gallon and would
require about an additonal 4 pounds. That was just about right.

For a "ROUGH" rule of thumb, where's the problem with physics?
Remember, we're talking about drysuits where the insulation isn't
significantly compressed at depth. I could be missing something, but I
just don't understand your point.

I should have clarified that I only use this method of estimating
weight needed when FIRST trying a substantially different set or
combination of undergarments, not for routine tweaking or fine-tuning.

An example is when I first combined a new Weezle Extreme Plus with
booties and wool socks, an additional ice cap hood under my regular
hood, plus dry gloves with doubled liners. Previously, I was using
layers of Polartec, one hood, neoprene mitts, fleece socks. By using my
rough rule of thumb, I came up with a good idea what weight would be
adequate and subsequent in-water tweaking was minimal to achieve a good
weighting. In fact, that tweaking was done at the end of the first dive
with a near-empty tank, so it was really quite accurate.

> > > How many Cold Water diver you know calibrate their "proper weight"
> > > (in lead) <diving in COLD WATER> to within 2 lbs or 1 kg? How
> > > many of them even KNOW what their proper amount of lead SHOULD be?
> >
> > Most, from what I've seen, get it pretty close, perhaps within 2 lbs of
> > the absolute minimum, but more likely a little further off.
>
> See, you're guessing, even for YOURSELF, judging from what you said
> about how you estimate your own needed lead.

Of course, I'm guessing about the other divers, but not for my own
weighting. I just didn't express my self very well when talking about
when I use my rough estimate.

My log of temps/insulation/weighting combinations has entries for
"minimum weighting" which I've determined after various dives with an
empty tank by removing weight until just barely able to submerge with
all air exhausted from the drysuit.

> > Very few of
> > us are concerned about how little weight somebody else has on or if
> > they've optimized their weighting.
>
> Or their own.

Ouch! Not true. They just give it less importance.

> That's where WARM WATER WIMPS are much more "proper weight" oriented
> because of the ease and freedom to DIVE WELL, without all the cold
> water gear and needed extra weight!
>
> Ultra trim trim plus minimal and proper weighting improves AIR
> CONSUMPTION EFFICIENCY. That is one reason I can dive longer on
> one tank of air than most.

Air wasting through excessive adjustments for buoyancy is the primary
issue, right?

The secondary issue is that buoyancy control becomes difficult, but
that's only when the overweighting is significant, I would say.

That's why I think the "purists" over-emphasize this issue, at least
when talking about a goal of being within two pounds of minimum
weighting.

And the seeking the ideal weighting is really most useful with tropical
gear and conditions, rather than the cases of compression of thicker
wetsuits at depth or drysuit undergarments needing less squeeze to be
warmer. Both of those cases tolerate the less than ideal weighting
without a significant problem.

Just starting a dive with a full tank creates less than ideal weighting
for much of the dive, despite claims of some that managing breathing
can overcome the excess.

> I was so fined tuned that I could tell the difference in the salinity
> of the water between the Atlantic (Bahamas) and the Caribbean!
> I have custom-made 1/4 lb pieces of lead that inserts into my
> weightbelt. Of course I had many 1 lb pieces too.

In the tropics, it's probably possible to fine-tune weighting to this
degree, that is, unless one had a gassy food for breakfast! 8^)

> I think a diver SHOULD be properly calibrated to within a couple of
> lbs. of the "proper weight". Most divers DON'T KNOW what that
> number is, period -- or how to calibrate it!

> > With a drysuit, which I use all year, proper amount of lead for me
> > varies, as I'll change the amount of my insulation to match temp and
> > activity level, even between dives sometimes. I might even add a couple
> > lbs if my undergarments are a little damp from perspiration from the
> > first dive, which might have made the end of the first dive a little
> > chilly. Adding that little bit of extra weight can make the difference
> > in warmth for the next dive. Of course, the trade-off is slightly more
> > wasted air from adjusting for buoyancy changes during the dive.

The next line really defines the parameters of improper weighting.

> I never quibble about any "couple of pounds" by anyone. It's the
> UNNEEDED 5, 10, or 20 lbs that are so commonly practiced by cold water
> divers that I crusade against.

Hear! Hear! Especially when that occurs in the tropics, as you
originally mentioned.

Overweighting makes a proportionately greater impact if the ideal
"proper' weighting should have been 10 lbs to start with, versus an
ideal of 30 lbs in cold water.

Totally with you on this one.

> >
> > I make the weighting adjustments from experience of trial and error,
> > occasionally referring to a log of what worked well to keep me warm
> > with various combinations of undergarments, hoods, gloves, etc. I don't
> > strive to get the optimum weighting for it's own sake because, frankly,
> > with a drysuit, it's not as warm.
>
> Proper weighting INCLUDES the consideration of proper (or chosen)
> warmth
> factor by the diver. So, if you needed 4 extra lbs for being WARMER,
> it's no different from someone wearing 7 mil instead of 5 mil (ro my
> 3 mil) to be sufficiently warm.
>
> BUt within EACH equipment (which includes the thickness of suit or
> the amount of insulation) there IS a "proper weight" that CAN be
> properly calibrated.

This is what I'm talking about. A "proper weight" for what purpose?

DUI's manual states a goal of "minimal air" in the drysuit. Others have
a similar standard. There's a point to the standard, for sure, for the
reasons we've discussed already.

So, I add 4 lbs to the minimum and find it significantly warmer. Of
course, my insulation works better with a little more loft in it. Maybe
thinsulate resists crushing better.

I just bridle at these notions of absolutes.

> It's the inadquacy of TRAINING agencies, which produced poorly trained
> Instructors, who in turn mis-taught proper weighting and buoyancy
> control, such as Nick Simicich and Dave Waller (the two I had used
> as examples) that led to students who pay no attention to over-
> weighting.
>
> It's that vicious cycle that needs to be corrected.
>
> >
> > Purists like to wear an abolute minimum of weight, but, in my drysuit,
> > I find I'm warmer with about 4 extra pounds. I think that achieves
> > better loft in the uppermost areas of the insulation when horizontal.
> > The trade-off is a little more air wasted when adjusting for changes in
> > buoyancy. Sure is nice to be warm as toast, though.
> >
> > With a wetsuit, in shallow water, the purists' absolute minimum may be
> > more beneficial to reduce such waste of air, but that benefit is
> > reduced at depths where suit compression requires more air to maintain
> > neutral buoyancy.
>
> You used the term "purist" rather improperly, if I may say so. I
> don't mind being called a "purist" if you don't attach all the
> untrue and derogatory implications in what you wrote!

Were the derogatory implications simply that I didn't value the goals
of the purists? Did I mistate their case? Or misunderstand it?

> My LYCRA suit has NO COMPRESSION whether I am at 15 fsw or 199 fsw
> where I frequently visit. :) My 1.5 mil titanium was adequate
> even for my dives in Bali where I dived comfortably in 65-70F
> enjoying nearly 45 minutes of the one and only mola mola I've ever
> seen.
>
> The needed AIR in the BC is mostly to compensate for the 5 lbs
> of extra weight of the AIR in the tank at the beginning of the dive!

Agreed. A tropical scenario.

A 7mm wetsuit's surface buoyancy compared to a 3mm reduces the validity
of the concern about ideal weighting to some extent because of
proportionality.

A drysuit is different as I've beaten to death above.

> > I think the purists' love of minimal weighting is best justified in
> > warm water conditions which require minimimal thermal protection. Then
> > the positive benefits would be pretty consistent.

> It's perfectly justified in diving with any equipment, in any cold
> water,
> at any temperature -- but you have to KNOW how to calibrate your
> minimum
> and calibrate it properly.
>
> That's the bottom line.

We apparently disagree as to whether it's EQUALLY important in those
three scenarios where the minimum weighting is so different in
magnitude and when compression or warmth are factored in.

We also disagree in HOW important it is. That may be the "purist"
distinction, which escapes me.

Dave C

Dave C wrote:
> Reef Fish wrote:
> > Dave C wrote:
> > > Reef Fish wrote:
> > >
> > > > BUOYANCY control is EVERYTHING in diving -- except it's a skill
> > > > seldom acquired by the Cold-Water trained divers.
> Snip
> > > I beg to differ, Bob.

We had one of the few meaty discussions I've had in rec.scuba.* for
some time. Actually what I had said had been said by me (and in the
ancient archives at least a decade ago).

Since we had more agreements in the ESSENTIALS of weighting and
buoyancy, I'll cut this short and provide mainly some clarifications
for issues you didn't catch or misunderstood.


> > Proper weighting can ONLY be calibrated, carefully, IN WATER, by
> > a diver who knows HOW.

I maintain this position, and in spite of you unfounded (I'll explain)
"rule of thumb", you did indicate that you knew how to calibrate
yourself near the end of the dive.


> We're in agreement here, but I'm suggesting the optimum weighting isn't
> all that important. Wasted air is the primary issue. Being able to
> react quickly enough with breath control or power inflator is the other
> issue. 5 lbs excess weight shouldn't even present much of a problem
> except in shallow water for less experienced divers.

"A 5 lb excess weight here, and a 5 lb there, and soon you'll talking
about a REAL weighty problem" -- to paraphrase an old Dirkson saying
about a billion here, and a billion there, you'll be soon taking about
real money!

First you have the extra 5 lbs of AIR (at the beginning of a dive),
add 5 lbs unneeded weight, that makes 10. When said diver is wearing
a 7 mil wetsuit in Coz, the compression at 80 fsw probably mean another
10 lbs or more. That's how a cold water diver was accelerating in
his DESCENT when I had to act fast to pull him by the tank because
the DM wasn't close enough.


> > > I have a quick rule of thumb for ROUGHLY estimating weighting required
> > > by undergarments is to put them in a plastic bag and ball them up with
> > > a little compression and estimate the volume they will displace in the
> > > water.
> >
> > That's a very bad "rule of thumb". That's not even proper physics!
> > Proper calibration is no different for cold and warm water divers.
> > Find out how much ACTUAL weight you'll need to remain neutral (with
> > All air out of the BC) when you're doing your safety stop at 15 fsw
> > with 500 psi.

> For a "ROUGH" rule of thumb, where's the problem with physics?

The physics is Archimedes principle. So, how do you estimate the
COLUME of the displacement of your wadded plastic bag that is
partially submerged? (In cu.ft??) You can't! And if you're off
by as little as 20% of the volume, you're off by more than 12 lbs
according to Mr. Archimedes!


> > Ultra trim trim plus minimal and proper weighting improves AIR
> > CONSUMPTION EFFICIENCY. That is one reason I can dive longer on
> > one tank of air than most.
>
> Air wasting through excessive adjustments for buoyancy is the primary
> issue, right?

Only for the grossly overweighted. The extra drag of the bulging
airbag, and the unnecessary excess baggage of lead all add to the
excess use of air for BREATHING to accomplish the same task of a
diver with minimum trim and minimal lead.

My Explorer Pro BC weighs merely THREE lbs (dry), but it has a
MAX lift of only 16 lbs, fully inflated. Even the smallest BC
for women now have about 40 lbs of lift! That's what my other
BC has, and it weighs about 9 lbs dry. Diving in currents in
Cozumel, you can REALLY tell the difference in the DRAG of these
BCs alone, even without the excess weight.

When divers are accustomed to having monkeys on their back, they
don't realize how much better thay can dive without those monkeys.


> Just starting a dive with a full tank creates less than ideal weighting
> for much of the dive, despite claims of some that managing breathing
> can overcome the excess.

You got that wrong. The excess 5 lbs is NECESSARY to be properly
weighted so that WITHOUT those 5 lbs or air near the end of a dive
the diver can remain neutrally buoyant with no air in the BC.

There is nothing wrong with putting air in the BC at the beginning
of a dive to compensate for those 5 lbs of air, at depth.

Only Lee Bell "claimed" he could manage by breath control alone
throughout the dive. Not many bad divers are as ignorant as Lee:

http://tinyurl.com/dx2l6


> > BUt within EACH equipment (which includes the thickness of suit or
> > the amount of insulation) there IS a "proper weight" that CAN be
> > properly calibrated.
>
> This is what I'm talking about. A "proper weight" for what purpose?

Good buoyancy control. Minimal diving effort in proper trim.


> > It's the inadquacy of TRAINING agencies, which produced poorly trained
> > Instructors, who in turn mis-taught proper weighting and buoyancy
> > control, such as Nick Simicich and Dave Waller (the two I had used
> > as examples) that led to students who pay no attention to over-
> > weighting.
> >
> > It's that vicious cycle that needs to be corrected.
> >
> > >
> > > Purists like to wear an abolute minimum of weight, but, in my drysuit,
> > > I find I'm warmer with about 4 extra pounds. I think that achieves
> > > better loft in the uppermost areas of the insulation when horizontal.
> > > The trade-off is a little more air wasted when adjusting for changes in
> > > buoyancy. Sure is nice to be warm as toast, though.
> > >
> > > With a wetsuit, in shallow water, the purists' absolute minimum may be
> > > more beneficial to reduce such waste of air, but that benefit is
> > > reduced at depths where suit compression requires more air to maintain
> > > neutral buoyancy.
> >
> > You used the term "purist" rather improperly, if I may say so. I
> > don't mind being called a "purist" if you don't attach all the
> > untrue and derogatory implications in what you wrote!
>
> Were the derogatory implications simply that I didn't value the goals
> of the purists? Did I mistate their case? Or misunderstand it?

A little bit of each. You seem to portray the "purist" as one who
would rather dive uncomfortably cold than add warmth and weight.
In your paragraph about "benefit is reduced at depth ..." has nothing
to do with a "purist's" notion of proper weighting.


> > The needed AIR in the BC is mostly to compensate for the 5 lbs
> > of extra weight of the AIR in the tank at the beginning of the dive!
>
> Agreed. A tropical scenario.

In ANY scenario. In freezing water, you need EXACTLY the same amount
of AIR to compensate for the weight of the air in the tank. You
simply need more air for the wetsuit compression effect.
..
>
> > > I think the purists' love of minimal weighting is best justified in
> > > warm water conditions which require minimimal thermal protection. Then
> > > the positive benefits would be pretty consistent.

I think you're still missing the point. The "minimal weighting" for
a 7mil wetsuit diver is the minimal weighting of a lycra suit diver
PLUS what it minimally takes to enable the diver to DESCEND, initially.
>

> We apparently disagree as to whether it's EQUALLY important in those
> three scenarios where the minimum weighting is so different in
> magnitude and when compression or warmth are factored in.

You are still hung up on the point about "minimal".

The "minimum weighting" IS very different in magnitude, depending
on the suit, diver, and diving. So, 6 lbs may be minimal for me
diving warm; 15 lbs may be minimal for me diving very cold; and
25 lbs may be minimal for YOU diving your drysuit comfortably.

But each is MINIMAL.

Nobody ever said 20 lbs or some arbitrary number is too much.
Well, I did say the diver wearing 75 lbs of lead diving in Cozumel
was using too much weight because I didn't see anyone pumping
helium into his blimp looking body.

> We also disagree in HOW important it is. That may be the "purist"
> distinction, which escapes me.
>
> Dave C

I hope this follow-up clarified most of those issues. If not,
then we'll just have to leave it the way it is, and let readers
decide for themselves what each of us meant, and/or makes more
sense.

-- Bob.

A couple of corrections of careless statements and typos.

Reef Fish wrote:
> Dave C wrote:
> > Reef Fish wrote:
> > > Dave C wrote:
> > > > Reef Fish wrote:
> > > >
> > > > > BUOYANCY control is EVERYTHING in diving -- except it's a skill
> > > > > seldom acquired by the Cold-Water trained divers.
> > Snip
> > > > I beg to differ, Bob.
>
> We had one of the few meaty discussions I've had in rec.scuba.* for
> some time. Actually what I had said had been said by me (and in the
> ancient archives at least a decade ago).
>
> Since we had more agreements in the ESSENTIALS of weighting and
> buoyancy, I'll cut this short and provide mainly some clarifications
> for issues you didn't catch or misunderstood.
>
>
> > > Proper weighting can ONLY be calibrated, carefully, IN WATER, by
> > > a diver who knows HOW.
>
> I maintain this position, and in spite of you unfounded (I'll explain)
> "rule of thumb", you did indicate that you knew how to calibrate
> yourself near the end of the dive.
>
>
> > We're in agreement here, but I'm suggesting the optimum weighting isn't
> > all that important. Wasted air is the primary issue. Being able to
> > react quickly enough with breath control or power inflator is the other
> > issue. 5 lbs excess weight shouldn't even present much of a problem
> > except in shallow water for less experienced divers.
>
> "A 5 lb excess weight here, and a 5 lb there, and soon you'll talking
> about a REAL weighty problem" -- to paraphrase an old Dirkson saying
> about a billion here, and a billion there, you'll be soon taking about
> real money!
>
> First you have the extra 5 lbs of AIR (at the beginning of a dive),
> add 5 lbs unneeded weight, that makes 10. When said diver is wearing
> a 7 mil wetsuit in Coz, the compression at 80 fsw probably mean another
> 10 lbs or more. That's how a cold water diver was accelerating in
> his DESCENT when I had to act fast to pull him by the tank because
> the DM wasn't close enough.
>
>
> > > > I have a quick rule of thumb for ROUGHLY estimating weighting required
> > > > by undergarments is to put them in a plastic bag and ball them up with
> > > > a little compression and estimate the volume they will displace in the
> > > > water.
> > >
> > > That's a very bad "rule of thumb". That's not even proper physics!
> > > Proper calibration is no different for cold and warm water divers.
> > > Find out how much ACTUAL weight you'll need to remain neutral (with
> > > All air out of the BC) when you're doing your safety stop at 15 fsw
> > > with 500 psi.
>
> > For a "ROUGH" rule of thumb, where's the problem with physics?
>
> The physics is Archimedes principle. So, how do you estimate the
> COLUME of the displacement of your wadded plastic bag that is
> partially submerged? (In cu.ft??) You can't! And if you're off
> by as little as 20% of the volume, you're off by more than 12 lbs
> according to Mr. Archimedes!

The "COLUME" was "VOLUME" of course. And I meant to say if you are
off by 2/10 of a cu ft (not 20%) you're off by 12 lbs. The point
was that it is virtually impossible to judge the VOLUME of
displacement accurately.
>
>
> > > Ultra trim trim plus minimal and proper weighting improves AIR
> > > CONSUMPTION EFFICIENCY. That is one reason I can dive longer on
> > > one tank of air than most.
> >
> > Air wasting through excessive adjustments for buoyancy is the primary
> > issue, right?
>
> Only for the grossly overweighted. The extra drag of the bulging
> airbag, and the unnecessary excess baggage of lead all add to the
> excess use of air for BREATHING to accomplish the same task of a
> diver with minimum trim and minimal lead.
>
> My Explorer Pro BC weighs merely THREE lbs (dry), but it has a
> MAX lift of only 16 lbs, fully inflated. Even the smallest BC
> for women now have about 40 lbs of lift! That's what my other
> BC has, and it weighs about 9 lbs dry. Diving in currents in
> Cozumel, you can REALLY tell the difference in the DRAG of these
> BCs alone, even without the excess weight.
>
> When divers are accustomed to having monkeys on their back, they
> don't realize how much better thay can dive without those monkeys.
>
>
> > Just starting a dive with a full tank creates less than ideal weighting
> > for much of the dive, despite claims of some that managing breathing
> > can overcome the excess.
>
> You got that wrong. The excess 5 lbs is NECESSARY to be properly
> weighted so that WITHOUT those 5 lbs or air near the end of a dive
> the diver can remain neutrally buoyant with no air in the BC.
>
> There is nothing wrong with putting air in the BC at the beginning
> of a dive to compensate for those 5 lbs of air, at depth.
>
> Only Lee Bell "claimed" he could manage by breath control alone
> throughout the dive. Not many bad divers are as ignorant as Lee:
>
> http://tinyurl.com/dx2l6
>
>
> > > BUt within EACH equipment (which includes the thickness of suit or
> > > the amount of insulation) there IS a "proper weight" that CAN be
> > > properly calibrated.
> >
> > This is what I'm talking about. A "proper weight" for what purpose?
>
> Good buoyancy control. Minimal diving effort in proper trim.
>
>
> > > It's the inadquacy of TRAINING agencies, which produced poorly trained
> > > Instructors, who in turn mis-taught proper weighting and buoyancy
> > > control, such as Nick Simicich and Dave Waller (the two I had used
> > > as examples) that led to students who pay no attention to over-
> > > weighting.
> > >
> > > It's that vicious cycle that needs to be corrected.
> > >
> > > >
> > > > Purists like to wear an abolute minimum of weight, but, in my drysuit,
> > > > I find I'm warmer with about 4 extra pounds. I think that achieves
> > > > better loft in the uppermost areas of the insulation when horizontal.
> > > > The trade-off is a little more air wasted when adjusting for changes in
> > > > buoyancy. Sure is nice to be warm as toast, though.
> > > >
> > > > With a wetsuit, in shallow water, the purists' absolute minimum may be
> > > > more beneficial to reduce such waste of air, but that benefit is
> > > > reduced at depths where suit compression requires more air to maintain
> > > > neutral buoyancy.
> > >
> > > You used the term "purist" rather improperly, if I may say so. I
> > > don't mind being called a "purist" if you don't attach all the
> > > untrue and derogatory implications in what you wrote!
> >
> > Were the derogatory implications simply that I didn't value the goals
> > of the purists? Did I mistate their case? Or misunderstand it?
>
> A little bit of each. You seem to portray the "purist" as one who
> would rather dive uncomfortably cold than add warmth and weight.
> In your paragraph about "benefit is reduced at depth ..." has nothing
> to do with a "purist's" notion of proper weighting.
>
>
> > > The needed AIR in the BC is mostly to compensate for the 5 lbs
> > > of extra weight of the AIR in the tank at the beginning of the dive!
> >
> > Agreed. A tropical scenario.
>
> In ANY scenario. In freezing water, you need EXACTLY the same amount
> of AIR to compensate for the weight of the air in the tank. You
> simply need more air for the wetsuit compression effect.
> .
> >
> > > > I think the purists' love of minimal weighting is best justified in
> > > > warm water conditions which require minimimal thermal protection. Then
> > > > the positive benefits would be pretty consistent.
>
> I think you're still missing the point. The "minimal weighting" for
> a 7mil wetsuit diver is the minimal weighting of a lycra suit diver
> PLUS what it minimally takes to enable the diver to DESCEND, initially.
> >
>
> > We apparently disagree as to whether it's EQUALLY important in those
> > three scenarios where the minimum weighting is so different in
> > magnitude and when compression or warmth are factored in.
>
> You are still hung up on the point about "minimal".
>
> The "minimum weighting" IS very different in magnitude, depending
> on the suit, diver, and diving. So, 6 lbs may be minimal for me
> diving warm; 15 lbs may be minimal for me diving very cold; and
> 25 lbs may be minimal for YOU diving your drysuit comfortably.
>
> But each is MINIMAL.
>
> Nobody ever said 20 lbs or some arbitrary number is too much.
> Well, I did say the diver wearing 75 lbs of lead diving in Cozumel
> was using too much weight because I didn't see anyone pumping
> helium into his blimp looking body.
>
> > We also disagree in HOW important it is. That may be the "purist"
> > distinction, which escapes me.
> >
> > Dave C
>
> I hope this follow-up clarified most of those issues. If not,
> then we'll just have to leave it the way it is, and let readers
> decide for themselves what each of us meant, and/or makes more
> sense.
>
> -- Bob.

Dave C wrote:

> 15 lbs is a remarkably low amount of lead, especially for a drysuit
> worn by an averaged size male, even with a very thin undergarment,

As I'm sure you've figured out, Bob is far smaller than the average man, and has a
very thin skin. The only thing buoyant about him is an exceedingly overinflated ego
compensation device.

--
Steve

The above can be construed as personal opinion in the absence of a reasonable
belief that it was intended as a statement of fact.

If you want a reply to reach me, remove the SPAMTRAP from the address.