Cruise Ship Dive Excursions

"Dave C" <dcalderbank@top.monad.net> wrote:

> Hugh, I'm sure Dick will have some good advice on diving Cape Ann, MA,
> but here are some links.
>
> I dive there often, so if you want more specifics about individual
> sites, feel free to email me at: dcalderbank AT cheshire DOT net
>
> Good shop:
>
> http://www.capeanndivers.com/
>
> And their page describing specific dive sites:
>
> http://www.capeanndivers.com/findadivesite.htm


Thanks, Dave. Our local dive club goes up to Cape Ann occasionally &
I've partly not had the interest since IIRC they choose to do it as a
dive/camping weekend.


-hh

"Dick" <devil505@adelphia.net> wrote:
>
> Make sure you have/rent a full wetsuit with boots, gloves & hood!

The same applies down here in NJ...offshore, the bottom temps are right
around 50F right now.


> Most divers around here go after lobster (State license required)
> which is always fun!

MA requires a lobster license even for hand collecting? How much does
that cost? Somehow I suspect that a weekend license isn't available,
either.


-hh

"Dave C" <dcalderbank@top.monad.net> wrote:
>
> 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 interesting and clearly effective ROM technique! Thanks.



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


But of course...that's nothing more than common sense.



-hh

Steve wrote:
> 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,

You can infer from this the depth of statistical ignorance of Steve,
that he thinks one who weighed 190 lbs is "far smaller" than the
average
man. That's not even smaller than those Canuch sows Steve likes to
date.

> and has a very thin skin.

Nobody who has a thin skin can survive a degenerate newsgroup like
rec.scuba.*, with dysfunctional mental midgets replacing each other.
I've seen them all, since 1989. An outlasted them all!

> The only thing buoyant about him is an exceedingly overinflated ego
> compensation device.

A moron making an oxymoron statement. How can something buoyant
COMPENSATE for overinflation?

Steve has the intelligence of an "average" <adj.> Canadian moose, has
an IQ far less than that of the "median" of a Canadian goose, but his
IQ is right at the "mode" of the IQ of rec.scuba posters.

Steve learned his statistics from the extinct-Professor Brannigan,
both of whom had been exposed of their extreme ignorance years ago,
and he still hasn't gotten over it. Changing his NAME didn't help.

-- Bob.
>
> --
> 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.

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.

It was good for me, too. Cigarette, Bob?

8^)

> 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.

SNIP
> > > > 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!

For this rough estimate of weighting, one can estimate the volume of
water that _will_ be displaced by the drysuit undergarments by a number
of methods.

Measuring the actual displacement IN WATER isn't necessary for such a
rough estimate, if that's what you thought I was doing.

Again, let me emphasize that this is a ROUGH estimate. How rough? Might
be plus or minus 10%, but it saves time and effort.

So, Rube Goldberg here balls up the undergarments in a plastic bag,
presses a little air out of the bag (to simulate the supposed "4 psi"
experienced in actual drysuit use), and measures the volume, calculates
the weight of displaced water.

Your choice: make it a rough sphere, measure the circumference and work
from there (what was it for volume of a sphere, 4/3 times Pi times the
cube of the radius? I forget).

Or, take a 5-gallon sheetrock mud pail with nice cylindrical shape and
shove the bag of undergarments in the pail with slight compression and
estimate the number of gallons occupied. You know the weight conversion
from there.

Why compress the undergarments to simulate 4 psi compression?

Well, that's the reported typical pressure of the experts' recommended
"proper" squeeze of the drysuit.

That's because 4.5 psi is probably when your nuts pop! Goddam purists!

I use a little less than proper compression, naturally. 8^)

Dave C

Reef Fish wrote:
> Dave C wrote:

> Note my key objection to your rough estimate was the "wadded plastic
> bag partially submerged".

Okay, now I'm befuddled and don't remember saying anything like that.
Rather than look through the crap I wrote, let me see if I can express
myself better.

> > For this rough estimate of weighting, one can estimate the volume of
> > water that _will_ be displaced by the drysuit undergarments by a number
> > of methods.
>
> You didn't say that before!

I probably left out some key antecedents to avoid belaboring the issue.
I know better now. Thanks for the heads-up. 8^)

You sure this whole thing wasn't a troll? I'm beginning to feel like
I've been dragged endlessly along the surface of the pond with my eyes
bulging out of my head.

You're not messing with me now, are ya, Bob? 8^)

> > Measuring the actual displacement IN WATER isn't necessary for such a
> > rough estimate, if that's what you thought I was doing.
>
> Yes! Archimedes required you to measure the DISPLACEMENT in water!

When drysuit diving, I succumb to convention and almost EQUALIZE the
pressure in my drysuit, so the 4 psi refers to the difference of
ambient pressure minus interior suit pressure, I believe. I should have
been more clear.

So, at depth, the undergarments are barely compressed by the outer
shell. That's true for any depth, if the pressure difference is
maintained.

The volume of water they displace can be estimated by... STOP ME BEFORE
I SAY IT AGAIN! You know the rest.

Can we agree the air layer created by the undergarments is the primary
positive buoyancy that we're trying neutralize with weight?

And that it's volume remains nearly constant throughout the dive?

My ROUGH rule of thumb, however inartfully expressed, is about
estimating the volume of that layer to get an initial weighting prior
to the dive, which would be followed by fine-tuning in-water.

> > Again, let me emphasize that this is a ROUGH estimate. How rough? Might
> > be plus or minus 10%, but it saves time and effort.
>
> That wasn't the problem. It was HOW you can get that close, even
> though
> 10% is hardly negligible. :)

It's ROUGH and soon to be fine-tuned in the water.

Does the near-equalization of interior suit pressure address the
"problem" you mention? Please describe the problem, because I'm not
seeing it.

Or is my measurement/approximation method in question?

> >
> > So, Rube Goldberg here balls up the undergarments in a plastic bag,
> > presses a little air out of the bag (to simulate the supposed "4 psi"
> > experienced in actual drysuit use), and measures the volume, calculates
> > the weight of displaced water.
>
> Wait! You haven't determined how much water it displaced it YET.
> The volume of the wadded plastic bag is immaterial. It doesn't
> matter if it's 1 cu. ft. and 1 cu ft of water would weigh about
> 62.5 lbs.

The estimated volume of the wadded up insulation in the plastic bag is
very close to the volume of water it will displace when it creates a
layer of air over the diver's body in the drysuit. That volume will
remain nearly constant throughout the dive as the diver equalizes or
nearly equalizes the air in the drysuit.

> > Or, take a 5-gallon sheetrock mud pail with nice cylindrical shape and
> > shove the bag of undergarments in the pail with slight compression and
> > estimate the number of gallons occupied. You know the weight conversion
> > from there.
>
> You are getting WARM, but still not close.

I need more elaboration of that statement. I don't understand what you
mean.

Well, I know you're close to a forehead-slapping moment, but suppose
the undergarments occupy about the equivalent volume of 4 gallons (4/5
the height of the aforementioned high-tech measuring pail). Those
undergarments, under only slight differential compression (4 psi
supposedly after nearly equilizing), will displace about the same
amount of water during the dive.

That volume of water displaced won't change much at different depths
because one continues to add air to the suit to avoid squeeze (and
maintain buoyancy for those of us who only use the bcd for back-up).

> Finally, the volume of the drysuit MAY or MAY NOT have much relevance
> to the amount of positive buoyancy cause by the AIR trapped inside
> the suit or its insulation garments.

It's the volume of the buoyant layer or air created by the insulation
in the drysuit that we're talking about, right? Not the volume of the
drysuit.

Also, the air trapped in the undergarments can migrate and escape, of
course, which is the basis for the maneuvers designed to counter a
feet-first out-of-control buoyant ascent.

> For the Viking drysuit I used, its VOLUME was quite large (the way
> you measure it), but I could dive with it in the pool, with no
> insulating garment, with 10 lbs of lead, because I could dump nearly
> all of the air between the suit and my body.

Bob, I never talked about measuring the volume of the drysuit, just the
volume occupied by the insulation which would create a layer of air.

> For insulating garments, you'll have to get Boyle to help.
>
> > Why compress the undergarments to simulate 4 psi compression?
>
> 4 psi? In your bath?

I should have specified that this is the differential pressure.

> > Well, that's the reported typical pressure of the experts' recommended
> > "proper" squeeze of the drysuit.
>
> Yeah, beware of the physics-deficient 'experts'. LOL!!!
> >
> > That's because 4.5 psi is probably when your nuts pop! Goddam purists!

> Really now?

A DIFFERENTIAL pressure of 4 psi will squeeze that suit onto you pretty
well. I like it a little looser.

> At 100 feet, the water pressure is 59.25 pounds per square inch (psi),
> I must have pretty tough nuts because I didn't even FEEL any cracking
> pressure when I was diving down to almost 300 feet.

Are you talking about a drysuit dive? If so, you've just made the case
that the air in the suit is equalized.

If it was a wetsuit dive, you know that there's no squeeze on your
body's solid or liquid masses, just on gaseous areas. And certainly the
wetsuit's compression doesn't make it squeeze the person in it.

What was your point about the 300 foot dive and water pressure?

Did your palm come up and slap your forehead yet? (Listening
carefully.)

If not, you may need to explain more to me because I'm not following
you.

8^)

Dave C

Dave C wrote:
> Reef Fish wrote:
> > Dave C wrote:
>
> > Note my key objection to your rough estimate was the "wadded plastic
> > bag partially submerged".
>
> Okay, now I'm befuddled and don't remember saying anything like that.
> Rather than look through the crap I wrote, let me see if I can express
> myself better.
>
> I probably left out some key antecedents to avoid belaboring the issue.
> I know better now. Thanks for the heads-up. 8^)

No problem. I was just trying to make sure I know you know what you
mean, in a slippery subject in which many fell -- like Nick Simicich
thought he needed 45 lbs of lead in his 1/4" wetsuit in Coz; and his
pal Hugh Huntzinger thought in-water calibration was "common sense",
little did he realize how FEW divers have an "common sense" that's
worth two cents.

At this point, I know that you know that we know that in-water
calibration is the only CORRECT and ACCURATE way of needed-lead
calibration, I am satisfied to leave it at that, lest the rest of
the readership gets tripped up in some minor technicalities.

> > Yes! Archimedes required you to measure the DISPLACEMENT in water!

That was just one of those technicalities.

> It's ROUGH and soon to be fine-tuned in the water.

That's a VERY important point. Based on my first hand experience
with many divers, it is a FACT that many of them never fine-tuned
their weight requirements, and unaware that they were overweighted
by 5 or more lbs, unnecessarily.

> > 4 psi? In your bath?

That was in part a joke to your statement below, and in part a
reminder that it's known that embolism CAN occur at small
differentials.
>
> > > That's because 4.5 psi is probably when your nuts pop! Goddam purists!

I still think your nuts are a bit too sensitive, don't you?

> What was your point about the 300 foot dive and water pressure?

That my nuts didn't pop at 150 psi pressure? 8^)
>
> 8^)
>
> Dave C

I think we had a good enough discussion on this topic. Let's leave it
at that, and not spoil the MAIN lessons on nits and nuts.

-- Bob.

Reef Fish wrote:
> Dave C wrote:
> >
> > > Note my key objection to your rough estimate was the "wadded plastic
> > > bag partially submerged".
> >
> > Okay, now I'm befuddled and don't remember saying anything like that.
> > Rather than look through the crap I wrote, let me see if I can express
> > myself better.
> >
> > I probably left out some key antecedents to avoid belaboring the issue.
> > I know better now. Thanks for the heads-up. 8^)

I said that with tongue-in-cheek, Bob, to provide you an opportunity to
amend your misquote and sort out the miscommunication. It's a bit
frustrating that you didn't, but I tried my best.

We just didn't seem to be able to pin down whether we had a MUTUAL
understanding of how drysuit undergarments displace water with constant
near-equalizing of interior suit pressure. And that a useful ROUGH
estimate of that displacement can be made very easily.

> No problem. I was just trying to make sure I know you know what you
> mean, in a slippery subject in which many fell --

SNIPPED the unnecessary disparaging comments about other posters; just
not my style, sorry, Bob.

> At this point, I know that you know that we know that in-water
> calibration is the only CORRECT and ACCURATE way of needed-lead
> calibration, I am satisfied to leave it at that, lest the rest of
> the readership gets tripped up in some minor technicalities.

This was your side issue that departed from the discussion of a useful
method of making a ROUGH estimate for the weight required by different
drysuit undergarments.

I give readers in this group more credit for being able to understand
the topic discussed and not get "tripped up".

> > > Yes! Archimedes required you to measure the DISPLACEMENT in water!
>
> That was just one of those technicalities.

Just not applicable, in this case, Bob. We apparently couldn't get back
on track.

> > It's ROUGH and soon to be fine-tuned in the water.
>
> That's a VERY important point. Based on my first hand experience
> with many divers, it is a FACT that many of them never fine-tuned
> their weight requirements, and unaware that they were overweighted
> by 5 or more lbs, unnecessarily.

I made that point about needing in-water fine-tuning in my original
statement on the topic, so long ago it seems like a bad dream. I just
didn't accompany the point with any condescending fanfare.

I think I mentioned the initial estimate was "ROUGH" a few times, too.
Can you say... "nauseating frequency"? 8^)

My original point was not to provide a primer in weighting, just a very
specific useful rule of thumb related to drysuit diving. It was pretty
clear.

> > > 4 psi? In your bath?
>
> That was in part a joke to your statement below, and in part a
> reminder that it's known that embolism CAN occur at small
> differentials.

The original context was completely different. You've brought up
another side issue... I'm getting dizzy...

SNIP

> I think we had a good enough discussion on this topic. Let's leave it
> at that, and not spoil the MAIN lessons on nits and nuts.
>
> -- Bob.

No doubt "as good as it gets", to quote the movie title, since it
mostly involved repeating and clarifying, probably unnecessarily, as I
think you would agree.

Maybe we can do better next time to actually hear and understand what
the other is saying.

Ya know, it was beginning to feel like I was forced to use Scrabble
letters to spell out what I was saying and to rephrase and clarify what
you were trying to say... or maybe what you were trying not to say.

When I tried to get you to clarify and discuss your own statements it
seemed like the board kept getting bumped! Was that intentional, Bob?
We can both be honest, right? 8^)

Oh, and I certainly don't view my opinions as "lessons", but it's nice
of you to say so!

J-8 O-1 K-5 E-1

Bob, put me down for 15 points, please. 8^)

Dave C

Reef Fish wrote:
> Dave C wrote:
> >
> > > Note my key objection to your rough estimate was the "wadded plastic
> > > bag partially submerged".
> >
> > Okay, now I'm befuddled and don't remember saying anything like that.
> > Rather than look through the crap I wrote, let me see if I can express
> > myself better.
> >
> > I probably left out some key antecedents to avoid belaboring the issue.
> > I know better now. Thanks for the heads-up. 8^)

I said that with tongue-in-cheek, Bob, to provide you an opportunity to
amend your misquote and sort out the miscommunication. It's a bit
frustrating that you didn't, but I tried my best.

We just didn't seem to be able to pin down whether we had a MUTUAL
understanding of how drysuit undergarments displace water with constant
near-equalizing of interior suit pressure. And that a useful ROUGH
estimate of that displacement can be made very easily.

> No problem. I was just trying to make sure I know you know what you
> mean, in a slippery subject in which many fell --

SNIPPED the unnecessary disparaging comments about other posters; just
not my style, sorry, Bob.

> At this point, I know that you know that we know that in-water
> calibration is the only CORRECT and ACCURATE way of needed-lead
> calibration, I am satisfied to leave it at that, lest the rest of
> the readership gets tripped up in some minor technicalities.

This was your side issue that departed from the discussion of a useful
method of making a ROUGH estimate for the weight required by different
drysuit undergarments.

I give readers in this group more credit for being able to understand
the topic discussed and not get "tripped up".

> > > Yes! Archimedes required you to measure the DISPLACEMENT in water!
>
> That was just one of those technicalities.

Just not applicable, in this case, Bob. We apparently couldn't get back
on track.

> > It's ROUGH and soon to be fine-tuned in the water.
>
> That's a VERY important point. Based on my first hand experience
> with many divers, it is a FACT that many of them never fine-tuned
> their weight requirements, and unaware that they were overweighted
> by 5 or more lbs, unnecessarily.

I made that point about needing in-water fine-tuning in my original
statement on the topic, so long ago it seems like a bad dream. I just
didn't accompany the point with any condescending fanfare.

I think I mentioned the initial estimate was "ROUGH" a few times, too.
Can you say... "nauseating frequency"? 8^)

My original point was not to provide a primer in weighting, just a very
specific useful rule of thumb related to drysuit diving. It was pretty
clear.

> > > 4 psi? In your bath?
>
> That was in part a joke to your statement below, and in part a
> reminder that it's known that embolism CAN occur at small
> differentials.

The original context was completely different. You've brought up
another side issue... I'm getting dizzy...

SNIP

> I think we had a good enough discussion on this topic. Let's leave it
> at that, and not spoil the MAIN lessons on nits and nuts.
>
> -- Bob.

No doubt "as good as it gets", to quote the movie title, since it
mostly involved repeating and clarifying, probably unnecessarily, as I
think you would agree.

Maybe we can do better next time to actually hear and understand what
the other is saying.

Ya know, it was beginning to feel like I was forced to use Scrabble
letters to spell out what I was saying and to rephrase and clarify what
you were trying to say... or maybe what you were trying not to say.

When I tried to get you to clarify and discuss your own statements it
seemed like the board kept getting bumped! Was that intentional, Bob?
We can both be honest, right? 8^)

Oh, and I certainly don't view my opinions as "lessons", but it's nice
of you to say so!

J-8 O-1 K-5 E-1

Bob, put me down for 15 points, please. 8^)

Dave C

Reef Fish wrote:
> Dave C wrote:
> >
> > > Note my key objection to your rough estimate was the "wadded plastic
> > > bag partially submerged".
> >
> > Okay, now I'm befuddled and don't remember saying anything like that.
> > Rather than look through the crap I wrote, let me see if I can express
> > myself better.
> >
> > I probably left out some key antecedents to avoid belaboring the issue.
> > I know better now. Thanks for the heads-up. 8^)

I said that with tongue-in-cheek, Bob, to provide you an opportunity to
amend your misquote and sort out the miscommunication. It's a bit
frustrating that you didn't, but I tried my best.

We just didn't seem to be able to pin down whether we had a MUTUAL
understanding of how drysuit undergarments displace water with constant
near-equalizing of interior suit pressure. And that a useful ROUGH
estimate of that displacement can be made very easily.

> No problem. I was just trying to make sure I know you know what you
> mean, in a slippery subject in which many fell --

SNIPPED the unnecessary disparaging comments about other posters; just
not my style, sorry, Bob.

> At this point, I know that you know that we know that in-water
> calibration is the only CORRECT and ACCURATE way of needed-lead
> calibration, I am satisfied to leave it at that, lest the rest of
> the readership gets tripped up in some minor technicalities.

This was your side issue that departed from the discussion of a useful
method of making a ROUGH estimate for the weight required by different
drysuit undergarments.

I give readers in this group more credit for being able to understand
the topic discussed and not get "tripped up".

> > > Yes! Archimedes required you to measure the DISPLACEMENT in water!
>
> That was just one of those technicalities.

Just not applicable, in this case, Bob. We apparently couldn't get back
on track.

> > It's ROUGH and soon to be fine-tuned in the water.
>
> That's a VERY important point. Based on my first hand experience
> with many divers, it is a FACT that many of them never fine-tuned
> their weight requirements, and unaware that they were overweighted
> by 5 or more lbs, unnecessarily.

I made that point about needing in-water fine-tuning in my original
statement on the topic, so long ago it seems like a bad dream. I just
didn't accompany the point with any condescending fanfare.

I think I mentioned the initial estimate was "ROUGH" a few times, too.
Can you say... "nauseating frequency"? 8^)

My original point was not to provide a primer in weighting, just a very
specific useful rule of thumb related to drysuit diving. It was pretty
clear.

> > > 4 psi? In your bath?
>
> That was in part a joke to your statement below, and in part a
> reminder that it's known that embolism CAN occur at small
> differentials.

The original context was completely different. You've brought up
another side issue... I'm getting dizzy...

SNIP

> I think we had a good enough discussion on this topic. Let's leave it
> at that, and not spoil the MAIN lessons on nits and nuts.
>
> -- Bob.

No doubt "as good as it gets", to quote the movie title, since it
mostly involved repeating and clarifying, probably unnecessarily, as I
think you would agree.

Maybe we can do better next time to actually hear and understand what
the other is saying.

Ya know, it was beginning to feel like I was forced to use Scrabble
letters to spell out what I was saying and to rephrase and clarify what
you were trying to say... or maybe what you were trying not to say.

When I tried to get you to clarify and discuss your own statements it
seemed like the board kept getting bumped! Was that intentional, Bob?
We can both be honest, right? 8^)

Oh, and I certainly don't view my opinions as "lessons", but it's nice
of you to say so!

J-8 O-1 K-5 E-1

Bob, put me down for 15 points, please. 8^)

Dave C