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Copied to techdiver to continue the thread.

Okay John, that is what I thought you meant in your first post. If you are
neutral at 20 fsw with up to 2000 psi remaining on your back, you have a
problem. If you have a decompression ceiling, you 
need to be able to remain at your shallowest stop (I like to be able to hover
just below the surface) with your tanks nearly EMPTY. You need to assume the
worst case scenario, such as a dive that 
went over the planned time, sharing gas, freeflows, losing a post and having to
isolate, etc. Being able to rocket to the surface does not imply proper
balancing, and when you add weight to 
account for the possible loss of that ten pounds of gas on your back, I wonder
if an eight pound belt will still be sufficient?

-Sean


--Original Message Text---
From: Johnscha@ag*.co*
Date: Thu, 6 Sep 2001 11:27:23 -0400

Sean
The 1500-2000psi is what was remaining in my back mix with around 1000-1200psi
in my deco bottle. My run times are 20-25 min. I am carrying approximately 
210 cu. ft. at 3300psi vs. 170 for the 80's at the same psi. I personally
wouldn't to push much more air in those AL's. The rig balances fine and if I
had to really 
get up, drop the weight belt and feel confident I could get up with a totally
inop BC. Besides I've got my lift bag if I need it. You just don't carry enough
gas in the 
80's, they are dangerous to overfill and too buoyant. I'll try your procedure
on my next flight.
John


-----Original Message-----
From: Sean T. Stevenson [mailto:ststev@un*.co*]
Sent: Thursday, September 06, 2001 11:19 AM
To: Techdiver Mailing List; John Schachleiter
Subject: RE: AL 80's


John, I am a drysuit diver so this discussion is purely academic, although I
have used twin 80's with additional weight. I'm not sure I entirely understand
your response. Do you mean to say that the 
1500 psi figure you quoted was your 50/50 bottle? If so, then you answered my
first question. I am curious, though, what your typical runtimes are. You
mentioned in a previous post that you like to 
keep your dives at about 200 fsw using a light trimix of 25% or less, with
bottom times of 20-25 minutes. How much gas are you actually consuming for this?

I am still waiting for an answer to the second question, namely how an eight
pound belt balances a rig that has over 13 pounds of consumed gas, plus
exposure suit compression. I trust you will be 
able to explain that with your usual eloquence.

As for the ILS, start at 30 feet AGL at full throttle, then just close your
eyes and use The Force...

-Sean



--Original Message Text---
From: Johnscha@ag*.co*
Date: Thu, 6 Sep 2001 08:40:09 -0400

Naw, I'm actually looking at the 50/50 mix. First of all, you're not carrying
enough mix in 80's without a serious and dangerous overfill and you still come
up short 
compared to my 232bar 85's. And they are 232bar tanks, same material sold in
Europe ! So at 3300-3500 psi I carry significantly more air. The trim is pretty 
good compared to the 98's that I use to dive. They sit higher, which helps me
to stand up with my busted back. They also have a narrow profile for
streamlining. 
Try them, you'll like em. Remember sonny, experience counts ! Sure you don't
want to give me some advice on that ILS ? Now let me see if I have a post from 
your legal buddy.
JWS

-----Original Message-----
From: Sean T. Stevenson [mailto:ststev@un*.co*]
Sent: Wednesday, September 05, 2001 5:30 PM
To: John Schachleiter; techdiver@aquanaut.com
Subject: Re: AL 80's


Still bitter about the oxygen deco explanation John? I would have thought that
such comments from a "kid" such as myself wouldn't have bothered you, as you
are obviously so much older, wiser 
and more experienced than myself. (Which raises the question, why do you even
bother to post here, if you already know everything?)

Having said that, I have a question or two regarding your post, cited below.
You mention that you are neutral at 20 fsw with 1500-2000 psi remaining in your
tanks. I am curious then, what happens 
in the hypothetical situation that your tanks are near empty and you have had
to jettison your deco bottle. Conventional wisdom would lead one to believe
that you would have excess positive 
buoyancy in this case, but I'm sure you can set us all straight on that. Please
explain.

Second, you mention that you wear an 8 lb weight belt, which implies that you
are using a high helium content in your back gas, since the minimum amount of
droppable weight you require is the 
weight of the consumed gas in your tanks. Assuming you were breathing air, with
twin Faber 85's and no overfill this would be at least 13.5 pounds, and then
you need to add weight to that to 
compensate for exposure suit compression, since you are wearing a neoprene
suit, and need to be able to get up when the suit compresses. Are you diving on
heliox? An eight pound belt doesn't 
intuitively seem to balance such a rig, but once again I will defer to your
greater knowledge and experience to explain how this is possible.

As I think from your post, but am not sure (see above questions), you
understand the concept behind a balanced rig, namely, that you have enough
weight to hold your shallowest stop with near 
empty tanks, while being able to swim up your rig from depth with full tanks
and compressed exposure suit, by dropping something (your belt). You use an
aluminum deco bottle, so you obviously 
understand why deco and stage bottles should be able to be jettisoned without
affecting your weighting.

I hope to be able to learn about balancing my rig from your responses to these
questions. As for the AL80 issue, in addition to proper balancing (as I
understand it), the 80's provide superior 
streamlining in a format that is easily accomodated on most boats and easy to
move around, given their light weight.

-Sean T. "the kid" Stevenson

PS - Just for the record, I never took such a brute force approach as to kick
the slats out of my crib. According to my mother, I undid all of the fasteners
(which were wingnuts), and the crib 
collapsed on me in the middle of the night - I took to sleeping in a bed at a
very young age.

Cheers.


--Original Message Text---
From: Johnscha@ag*.co*
Date: Wed, 5 Sep 2001 14:27:31 -0400

AL 80's 


Jeez, I really should lay off, but I just can't help myself. I think ya'll are
smoking dope on mandating AL 80's as " the only way " to dive, open ocean, in a
wet 
suit. I've been using Faber double 85's with a shortly, farmer john, vest, AL40
deco bottle and 8lb weight belt for a while. I am about neutral on my 20' hang 
with 1500 - 2000 psi remaining in the tanks and a near empty BC. I will kiss
your collective butts at payday muster if I can't swim this rig off the bottom
any day 
of the week while safely carrying more gas ! No comments from Sean and his
legal beagle buddy please. I suspect I was doing this stuff when he was kicking 
the slats out of his crib. Probably like to tell me how to shoot an ILS to
minimums. 















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<FONT FACE="MS Sans Serif" DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8"
DEFAULT="SIZE">Copied to techdiver to continue the thread.<BR>
<BR>
Okay John, that is what I thought you meant in your first post. If you are
neutral at 20 fsw with up to 2000 psi remaining on your back, you have a
problem. If you have a decompression ceiling, you need to be able to remain at
your shallowest stop (I like to be able to hover just below the surface) with
your tanks nearly EMPTY. You need to assume the worst case scenario, such as a
dive that went over the planned time, sharing gas, freeflows, losing a post and
having to isolate, etc. Being able to rocket to the surface does not imply
proper balancing, and when you add weight to account for the possible loss of
that ten pounds of gas on your back, I wonder if an eight pound belt will still
be sufficient?<BR>
<BR>
-Sean<BR>
<BR>
<BR>
--Original Message Text---<BR>
<B>From:</B> Johnscha@ag*.co*<BR>
<B>Date:</B> Thu, 6 Sep 2001 11:27:23 -0400<BR>
<BR>
<FONT COLOR=0000ff><FONT FACE="Arial"><FONT SIZE="2"
POINTSIZE="10">Sean<FONT COLOR=000000 DEFAULT="COLOR"><FONT FACE="MS Sans
Serif" DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8" DEFAULT="SIZE"><BR>
<FONT COLOR=0000ff><FONT FACE="Arial"><FONT SIZE="2"
POINTSIZE="10">The 1500-2000psi is what was remaining in my back mix with
around 1000-1200psi in my deco bottle. My run times are 20-25 min. I am
carrying approximately 210 cu. ft. at 3300psi vs. 170 for the 80's at the same
psi. I personally wouldn't to push much more air in those AL's. The rig
balances fine and if I had to really get up, drop the weight belt and feel
confident I could get up with a totally inop BC. Besides I've got my lift bag
if I need it. You just don't carry enough gas in the 80's, they are dangerous
to overfill and too buoyant. I'll try your procedure on my next flight.<FONT
COLOR=000000 DEFAULT="COLOR"><FONT FACE="MS Sans Serif"
DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8" DEFAULT="SIZE"><BR>
<FONT COLOR=0000ff><FONT FACE="Arial"><FONT SIZE="2"
POINTSIZE="10">John<FONT COLOR=000000 DEFAULT="COLOR"><FONT FACE="MS Sans
Serif" DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8" DEFAULT="SIZE"><BR>
<BR>
<BR>
<FONT FACE="Tahoma"><FONT SIZE="2" POINTSIZE="10">-----Original
Message-----<BR>
<B>From:</B> Sean T. Stevenson [mailto:ststev@un*.co*]<BR>
<B>Sent:</B> Thursday, September 06, 2001 11:19 AM<BR>
<B>To:</B> Techdiver Mailing List; John Schachleiter<BR>
<B>Subject:</B> RE: AL 80's<BR>
<BR>
<BR>
<FONT FACE="MS Sans Serif" DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8"
DEFAULT="SIZE">John, I am a drysuit diver so this discussion is purely
academic, although I have used twin 80's with additional weight. I'm not sure I
entirely understand your response. Do you mean to say that the 1500 psi figure
you quoted was your 50/50 bottle? If so, then you answered my first question. I
am curious, though, what your typical runtimes are. You mentioned in a previous
post that you like to keep your dives at about 200 fsw using a light trimix of
25% or less, with bottom times of 20-25 minutes. How much gas are you actually
consuming for this?<BR>
<BR>
I am still waiting for an answer to the second question, namely how an eight
pound belt balances a rig that has over 13 pounds of consumed gas, plus
exposure suit compression. I trust you will be able to explain that with your
usual eloquence.<BR>
<BR>
As for the ILS, start at 30 feet AGL at full throttle, then just close your
eyes and use The Force...<BR>
<BR>
-Sean<BR>
<BR>
<BR>
<BR>
--Original Message Text---<BR>
<B>From:</B> Johnscha@ag*.co*<BR>
<B>Date:</B> Thu, 6 Sep 2001 08:40:09 -0400<BR>
<BR>
<FONT COLOR=0000ff><FONT FACE="Arial"><FONT SIZE="2"
POINTSIZE="10">Naw, I'm actually looking at the 50/50 mix. First of all, you're
not carrying enough mix in 80's without a serious and dangerous overfill and
you still come up short compared to my <B>232bar </B>85's. And they are
232bar tanks, same material sold in Europe ! So at 3300-3500 psi I carry
significantly more air. The trim is pretty good compared to the 98's that I use
to dive. They sit higher, which helps me to stand up with my busted back. They
also have a narrow profile for streamlining. Try them, you'll like em. Remember
sonny, experience counts ! Sure you don't want to give me some advice on that
ILS ? Now let me see if I have a post from your legal buddy.<FONT
COLOR=000000 DEFAULT="COLOR"><FONT FACE="MS Sans Serif"
DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8" DEFAULT="SIZE"><BR>
<FONT COLOR=0000ff><FONT FACE="Arial"><FONT SIZE="2"
POINTSIZE="10">JWS<FONT COLOR=000000 DEFAULT="COLOR"><FONT FACE="MS Sans
Serif" DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8" DEFAULT="SIZE"><BR>
<BR>
<FONT FACE="Tahoma"><FONT SIZE="2" POINTSIZE="10">-----Original
Message-----<BR>
<B>From:</B> Sean T. Stevenson [mailto:ststev@un*.co*]<BR>
<B>Sent:</B> Wednesday, September 05, 2001 5:30 PM<BR>
<B>To:</B> John Schachleiter; techdiver@aquanaut.com<BR>
<B>Subject:</B> Re: AL 80's<BR>
<BR>
<BR>
<FONT FACE="MS Sans Serif" DEFAULT="FACE"><FONT SIZE="1" POINTSIZE="8"
DEFAULT="SIZE">Still bitter about the oxygen deco explanation John? I would
have thought that such comments from a "kid" such as myself wouldn't have
bothered you, as you are obviously so much older, wiser and more experienced
than myself. (Which raises the question, why do you even bother to post here,
if you already know everything?)<BR>
<BR>
Having said that, I have a question or two regarding your post, cited below.
You mention that you are neutral at 20 fsw with 1500-2000 psi remaining in your
tanks. I am curious then, what happens in the hypothetical situation that your
tanks are near empty and you have had to jettison your deco bottle.
Conventional wisdom would lead one to believe that you would have excess
positive buoyancy in this case, but I'm sure you can set us all straight on
that. Please explain.<BR>
<BR>
Second, you mention that you wear an 8 lb weight belt, which implies that you
are using a high helium content in your back gas, since the minimum amount of
droppable weight you require is the weight of the consumed gas in your tanks.
Assuming you were breathing air, with twin Faber 85's and no overfill this
would be at least 13.5 pounds, and then you need to add weight to that to
compensate for exposure suit compression, since you are wearing a neoprene
suit, and need to be able to get up when the suit compresses. Are you diving on
heliox? An eight pound belt doesn't intuitively seem to balance such a rig, but
once again I will defer to your greater knowledge and experience to explain how
this is possible.<BR>
<BR>
As I think from your post, but am not sure (see above questions), you
understand the concept behind a balanced rig, namely, that you have enough
weight to hold your shallowest stop with near empty tanks, while being able to
swim up your rig from depth with full tanks and compressed exposure suit, by
dropping something (your belt). You use an aluminum deco bottle, so you
obviously understand why deco and stage bottles should be able to be jettisoned
without affecting your weighting.<BR>
<BR>
I hope to be able to learn about balancing my rig from your responses to these
questions. As for the AL80 issue, in addition to proper balancing (as I
understand it), the 80's provide superior streamlining in a format that is
easily accomodated on most boats and easy to move around, given their light
weight.<BR>
<BR>
-Sean T. "the kid" Stevenson<BR>
<BR>
PS - Just for the record, I never took such a brute force approach as to kick
the slats out of my crib. According to my mother, I undid all of the fasteners
(which were wingnuts), and the crib collapsed on me in the middle of the night
- I took to sleeping in a bed at a very young age.<BR>
<BR>
Cheers.<BR>
<BR>
<BR>
--Original Message Text---<BR>
<B>From:</B> Johnscha@ag*.co*<BR>
<B>Date:</B> Wed, 5 Sep 2001 14:27:31 -0400<BR>
<BR>
AL 80's <BR>
<BR>
<BR>
<FONT FACE="Arial"><FONT SIZE="2" POINTSIZE="10">Jeez, I really should
lay off, but I just can't help myself. I think ya'll are smoking dope on
mandating AL 80's as " the only way " to dive, open ocean, in a wet suit. I've
been using Faber double 85's with a shortly, farmer john, vest, AL40 deco
bottle and<B> 8lb weight belt</B> for a while. I am about neutral on my
20' hang with 1500 - 2000 psi remaining in the tanks and a near empty BC. I
will kiss your collective butts at payday muster if I can't swim this rig off
the bottom any day of the week while safely carrying more gas ! No comments
from Sean and his legal beagle buddy please. I suspect I was doing this stuff
when he was kicking the slats out of his crib. Probably like to tell me how to
shoot an ILS to minimums. <FONT FACE="MS Sans Serif" DEFAULT="FACE"><FONT
SIZE="1" POINTSIZE="8" DEFAULT="SIZE"><BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>
<BR>

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