On Wed, 11 Feb 2004 13:44:44 +0000, Andy M Johnson <[log in to unmask]>
wrote:

>>>Hmmmm.....I regulary dive in the Red Sea which is VERY salty and various
>>>other locations & have never noticed any difference in weight required.

>>That's because you CWWs (Cold Water Wimps) are typically OVER-weighted.

That comment is addressed to the fact that you "never noticed", not
the specific amount.


>Sorry,  I should have been more specific, I didn't mean UK dry suit
>diving.

That was understood.  In fact, I was surprised (not having dived in
the Red Sea but always knew it to be WARM water diving) that you
ever had to dive with more a 1 mil suit.  So, that assumption was
not made, nor relevant.


>But from your experience & observations it would seem the difference is
>ounces rather than pounds.

NOW we get to the crux of the matter.  The word "pounds" never appeared
in any of the posts until now.  :-)

Specifically,

AJ> Without doing the research & maths my gut feel is that the bouyancy
AJ> characteristics would not change by more than an ounce or two.

The keywords are "an ounce or two".

That was when I commented on having NOTICED (in the range between
4 oz to 16 oz -- which are still ounces <BG>) that it is DEFINITELY
noticeable, if your buoyancy is fine-tuned.

My smallest unit:     4 oz =  4 times "an ounce" and 2 times "two".
Two of those pieces   8 oz =  8 times "an ounce" ...
Three of those pices 12 oz = 12 times "an ounce" ...

all of which are still LESS than a pound.

MOST divers (experienced or not) would not notice the difference
of 1 lb in the total lead requirement for appropriate/comfortable
buoyancy in lycra to 1 mil suits.

My example about the Bahamas and the Caribbean is, to the best of
my knowledge, only mentioned by ME, about the salinity of water and
the lead requirement.

Part of that is perhaps due to the fact that most people thought
the Bahamas are part of the Caribbean.  :-)


>So anyhow, I need a new torch because they don't do 4oz weights in Egypt
>:-)

I am a self-taught small-lead-weight craftsman too.  :-)

My (I mean Sue's) POS (aka ReefMaster 200 digital) included a piece
of accessory of lead that can be inserted into the housing to make
it NEUTRAL (as in perfect buoyancy) as supposed to slightly positive
so that it would not sink if dropped.

I think that piece of 12 oz lead weight cost about $20.

I hand-crafted a piece (actually for lack to time to wait for the
shipment rather than trying to save 20 bucks <G>) which included
a circular piece with an interior large hole for the piece, a
small hole to see through, as well as four little semi-circular
cuts to fit the pegs to keep the piece from sliding ... and
finally had it sanded down to 12 ozs.  :-)

I almost forgot about the plastic coating -- it was a modified
piece from the one of the several 1 lb pieces of lead I made (with
lucite/plastic coating) that Sue still uses in her weightbelt.


I have a personal collection of about 80 lbs of unused dive-lead,
ranging from 2 lbs to 6 lbs, bought or found over the years.
I have picked up well over 200 lbs of lead in Cozumel alone (at
depths usually below 120 fsw) from pieces and weightbelts dropped
by overweighted and underskilled divers.  :-)

All of that are evidence that most divers don't pay much attention
to buoyancy ocntrol OR the amount of lead used when they dive.

That was the source of extended flamewars between Nick Simicich and
myself over the years, because Nick did his sloppy math and sloppy
physics and came to the conclusion that he needed 45 lbs of lead
wearing a 3 mil suit, and flame me and every piece of published
article (excellent ones I might add) that was published in the Skin
Diver mag on Buoyancy Control.

It's ALL in the archives.  :-))

I came to MY physics conclusion that his head must have been HOLLOW. :-)

I think my inferential physics was correct.

-- Bob.