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Anyway, that is very interesting that you have thought out some type of
speargun device from a sub.
Since my first realization that
I could actually build a working sub I started thinking about what I would like
to use it for. Research is always an option, but ocean farming as alway
peaked my interest. It's something that is starting to happen in different
parts of the world now on a limited basis.
With sport spearfishing there are limits on how many fish you
can take and what species are in season and so forth. I personally have
only spearfished out at our local islands with a Hawwaian sling with only mask
and snorkle. But what I'm wondering is., Bill you said that
underwater "firearms" are illegal, what it you shot a air powered spear at
a fish that you are going to eat ( not a protected fish) and the spear is not
connected by a cable. ( It seems like if you had a cable you might be
asking for entaglement problems.) Would it be possible once
the spear penetrated the fish that a small air pladder could be activated which
would send the fish to the surface?
Brian
----- Original Message -----
Sent: Wednesday, March 30, 2005 4:01
PM
Subject: RE: [PSUBS-MAILIST] Discharging
Batteries
The guns will be "fired" from inside the
sub (charging a pressure reservoir, locking it out, and then redirecting the
air to the "chamber" of the gun), all done with normal steel pipe and ball
valves. A piston located forward of the chamber will push the spear
out of the barrel and between two rods spaced far enough apart to allow the
spear to pass but not the piston. The key to keeping the spear
straight is using one or more sabots inside the barrel, since the piston will
be much bigger than the spear. The sabots will keep the spear aligned
until it exits the barrel and the piston will push them out to clear the
barrel after a shot (for possible reloading?). A short length of
steel cable is wound around the piston and anchored to it. Once
speared, at least in my experience, most fish dive. The two bars
mentioned above will capture the piston and cause the fish to "ratchet"
down to somewhere below the sub where they will dangle until the sub surfaces
and they are manually captured. Worst case, they flail around above
until expired, eventually sinking through the ratcheting
mechanism to dangle below the sub. I plan to surface after a couple
of shots to keep the sharks from benefiting from all my hard work.
I am pretty sure I can build a gun for about as much as a decent hand-held
pneumatic gun (<$300.00). The motivation for all this is the idea of
spear-fishing at 1Atm for SEVERAL HOURS at a time with no concern for dive
tables, being able to survey a fishing area without eating into dive time,
having the ability to patiently wait for prey, not worrying about how big a
fish is and if I have enough air to fight it ( I got real stupid once and
shot a 35lb barracuda with little air left in a single
tank @ 80ft, the dive master rightly refused to let me have a second
dive that day), and dramatically increasing the amount and type of fish
caught (provided I get the gun right!!). This type of hunting fits
unbelievably well with a psub. The sub only has to be able to submerge
to certain depths (in my case, about 120' maximum, normally 45-90'), manuever
for very short periods of time, and hold a somewhat stable position for 30
minutes or more (fish are curious, they will come to you). I've speared
most of my fish sitting on cross braces on oil platforms, trying to conserve
air by not swimming around too much. My son's a commercial diver and he
literally has to push them out of his way when he's doing hull cleanings, prop
maintenance, etc. I think they will flock to a sub, especially if it's
"just sitting there" with a basket of crushed barnacles on top of
it:).
Best Regards,
Cliff
Cliff,
How are you going to
spearfish while you're inside the sub? How will you retrieve the
fish? Are you thinking reeling them back into next to the
ship? I haven't totally figured what type of spearfishing unit
I'm going to use.
Brian
----- Original Message -----
Sent: Wednesday, March 30, 2005 12:04
PM
Subject: RE: [PSUBS-MAILIST]
Discharging Batteries
Good Question. I actually have
a few of reasons. Putting them under the seats gets them
conveniently out of the way but still easily accessible for change-out
(from a support boat), eliminates several cubic feet of cabin
space that would otherwise have to be displaced by adding more
weight, doesn't add to the complexity of the shape of the pressure
hull, and minimizes the amount of "second skin" that I will have to add to
smooth the outside shape since I intend to spear fish with pneumatic
spearguns mounted on the sub. I don't want fish on steel
cables getting tied up on battery pods, motors, etc. Due to the
distance I have to travel to fish, I have resigned myself to building a
towable sub. For practical reasons it will have to be as small as
possible and somewhat planeable(sp?) when towed. I think I hit most
of the reasons.
Thanks Again for your
Input,
Cliff
-----Original
Message-----
From: owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org]On Behalf Of
Akins
Sent: Wednesday, March 30, 2005 1:12 PM
To:
personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST]
Discharging Batteries
Cliff,
Why not just put your batteries outside the cabin in battery pods?
That way you don't have the problem to begin with.
Kindest Regards,
Bill Akins.
----- Original Message -----
Sent: Tuesday, March 29, 2005
3:12 PM
Subject: RE: [PSUBS-MAILIST]
Discharging Batteries
Actually, that's what prompted my
question. I blew a car battery up trying to jump-start the
wife's car. Fortunately, I had been using a skill-saw in the
garage moments before and was still wearing safety glasses.
After a really fast shower I retrieved the safety glasses
and noticed that they were literally dripping with slimy acid residue,
I still get chills thinking about it. Since this occurred while
attempting to charge the battery, I was under the assumption
that charging was the culprit. Yours is the first time I've
heard of a battery exploding while under "normal" load.
I'll probably go with the AGM batteries and put some lockable 1/8"
steel plate between myself and the batteries anyway. Not sure
what I can do to ventilate the gases in the event of an explosion, I
was planning to shut down all electrical systems, switch to
emergency air (scuba regulators/mouthpieces), and get to the
surface asap.
Thanks Everybody,
Cliff
Hi Cliff,
About sitting on batteries in a sub... Have you ever
seen/heard one explode? It CAN happen while discharging,
especially if there is a poor or corroded connection at the battery
pole enough that when you pull a fairly large current, a spark may
occur. Last summer my son got in my pickup and went to start
it. I had been driving it 15 min. earlier. When he hit
the starter, the battery exploded under the hood with a sound of a
deer rifle shot. Acid went all over the engine
compartment, the battery was split wide open, and luckily, there
were no dents in the hood.
Moral of the story... IF you have to have them in the
compartment with you... make sure you are shielded from an
explosion, BUT make sure there is still ventilation to allow any
explosive gas to dissipate. PS Of course, my
pickup didn't have
hydrocaps!
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