Chuck

    You may not understand the primary application for which I am using this 
device or the equipment configuration it is primarily used with.    If you 
will review my original post you will see that I am using this for solo sump 
diving,  this means that I am using independent waist mounted sidemounts.   
The tank valves can be easily be reached at waist level and do not require me 
to reach behind my back as you would with a standard backmounted system.   
When I indicated that I could allow the unit to hang from my wrist while I 
completed a task that required both hands I did not intend to imply that I 
would do so while I swam through the sump.  When I have completed a task I 
replace the cutters into there holder.   This takes a few seconds and is easy 
to accomplish.   In use the unit is reasonably streamlined and stays in its 
holder until I take positive actions to remove it.   I also mentioned that I 
do use it on some wreck dives with backmounts.  Because of the design of the 
holder and the position of the unit on my wrist I have no concern that It will 
become  tangled behind me if I need to reach for a valve.    This would be 
like trying to catch a fish with a straight hook with no barbs.......... It 
just does not work that way...............



As I noted in my first post this approach has advantages and disadvantages 
like any solution to a problem.   In the unique environment in which we dive 
the advantages out weight the disadvantages so we use it.    The big advantage 
is that it can not be lost so that when you need it to save your life it is 
there....... A break away lanyard would defeat this purpose...........carrying 
a dozen cutters would really create a hazard.....and might get me a spot on 
the stroke page as well...............

 Now if I was diving a scooter in big warm Florida cave than I would be in an 
environment in which stream lining would be critical and one in which I would 
have team members I could also depend on, I would not be solo.  I would also 
have warm hands so I would not need to  use this system.  A cold water dive in 
a sump solo is a different animal so I do use this system and it 
works..............







                                                     JOSEPH KAFFL
                                              SUMPDIVER@MS*.CO* 



  

 

----------
From:  CHKBOONE@ao*.co*
Sent:  Tuesday, April 01, 1997 1:03 PM
To:  techdiver@aquanaut.com
Subject:  Re: things that cut


Joseph,

    Somehow I missed that you intended to use this cutter regularly with =
it
dangling from your wrist as you work.   Make sure you use a break away se=
t up
where the lanyard is concerned.   Pull it out - use it - stow it - all in=
 one
motion, don't ever leave it dangling.   Or! eliminate the cord and take
enough cutters so that you can afford to drop several - possibly the bett=
er
option in the long run.=20

   Picture yourslef having to suddenly reach for your valves or a regulat=
or
on your chest with this weight on the end of a loop hanging from your wri=
st.
   When that hiss occurs you will probably reach back for that valve
instinctively and if the cord and cutters are hanging from your wrist at =
the
time they could easily wrap around the manifold or drop between the hoses=
 and
not come out in the other direction - you will be screwed badly with your
hand trapped behind your head or under your chin.   By the same token if
caught on the line you are working on you won't be able to reach for your
valves.
   At any rate having this lanyard deployed ties you up with the task of
stowing it before you can use your hand around your rig safely.

    The little knife I keep under my slate is only 1/4" thick, 1" wide an=
d 3"
long retracted into the case and there is a piece of white elastic about
1/32" diameter (like a tiny bungie) that runs through a hole in the knife
case.   I found the elastic in a fabric store and it is strong enough to =
keep
the thing from dropping away but will break easily under very little
pressure.   It is also long enough that there is no pressure put on the k=
nife
by the cord when in use .   The entire slate set up is form fitted - no e=
dges
or corners sticking out so that the whole thing, knife, watch, and all is
practically a smooth bulge on my forearm.   By wraping the little bungie
around my wrist it remains flush to the arm and just under the cuff of th=
e
wetsuit where it should not snag on gear and is easy to re-store quickly.=
=20

   I was in the process of responding to your second post when I got an
e-mail from
George I. pleading that we both rethink this issue and asking me to relay=
 it
to you. =20
He did not elaborate or offer any details other than that it should be on=
 the
belt.   I have asked George to comment further and it may well be that he
thinks anything mounted in the area of the wrist is a disaster.   We will
see, I hope.

   I believe the wrist position is convenient and useful but it needs to =
be
designed
carefully to insure secure retention (in the sheath), low clutter and
profile, and no
entanglement threat.   Freedom to move the hands instantly to any part of=
 the
rig is
important in the overhead environment especially in an emergency and they
will be tied up by the need to re-store these deployed lines or any held
objects.

   Put a breakable elastic cord on it, make absolutely sure it can=92t be
accidentally
released from the sheath, and don=92t ever leave it dangling.   If you dr=
op it
while using it you will not loose it and by re-storing it immediately you
will reduce the risk of having it deployed if you need to get to the rig
quickly (if it is, just break it free and drop it).   If it does get tang=
led
up you can break it free easily.      =20
You will still need a spare, or two !


Chuck

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My orginal post....................

Some thoughts from the world of sumps...................



 The standard line cutter used by the NEST,  North East Sump Exploration Team, 
consists of a pair of stainless steel EMT scissors  worn on the wrist of the 
right arm or for south paws the left.  The sheath is modified with a plastic 
stiffener so that it maintains its shape when the scissors are removed.  The 
scissors are attached with a lanyard to the wrist.  A small backup cuter is 
also carried stowed else where on the rig that can be accessed one handed.


This system is designed for the conditions under which we dive and like any 
approach has advantages and disadvantages.  We generally dive in cold water 
and in most cases solo with poor to no visibility and are moving at relatively 
slow speeds.  


The line cutters are carried for two main reasons, the first being routine 
line cutting when splicing line or replacing worn sections.  The second as the 
final solution to a line entangle ment that can not be resolved in any other 
way.  


 
The prime advantage of our system is that the cutter is always close at hand 
and can not be lost or dropped.   Lets face it any time you find yourself in a 
position in a sump when you might have to cut your line it has been a real bad 
day. 

  Picture yourself in a sump tangled hopelessly in your line.  You are feeling 
really stupid because you should not be in this position to begin with so 
something else has probably gone wrong as well to get you here.  You are 
exited and the adrenaline is pumping,  you have not panicked yet,  but you are 
not as coordinated as you would like because of all of those chemicals pumping 
through your body.  To all this add cold or possibly numb hands.
You reach for your knife and oups.... you drop it, it falls out of reach and 
disappears into the near zero visibility..........you die..........

   With our system you release your line cutter and you can drop it as long as 
your gas lasts and not loose it.   If you are conducting routine line 
maintenance you can even let it dangle for a short period while you use both 
hands for a task.     


The disadvantage is that wearing the unit on the wrist does add some clutter 
and reduces streamlining.    

In balance for our diving conditions the advantages out weigh the 
disadvantages.   I also use the same system for most of my wreck diving and 
find that it works equally well.


                                                 JOSEPH KAFFL
                                                SUMPDIVER@MS*.CO*  





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