Hi Pierre;
I'd like to give you some "food for thought" on your decision.
If you are going to pressurize compensate your motors, there's no real
problem to pressurize your battery box as well... it's simply more volume.
The weight of your sub is determined by the size (volume) of the bubble you're
trying to sink.
In my judgement, the PVC is a much simpler solution, widely available, easy
to work with, inexpensive, non-corrosive, strong, lightweight, easily capable of
withstanding minor pressure variations. Simply put, PVC
is ideal for an ambient sub.
If you are going to build big heavy steel battery boxes (tubes?) filled
with batteries and lead, can you jettison them in an emergency? I would
hope so. That's a lot of weight. Steel rusts anyway... but add
oxygen from electrolysis, add salt water, add electrical potential for galvanic
action, the conductivity of steel, and.... well, I like the
plastic idea better for an ambient sub.
But that's just my opinion.
Stan
In a message dated 1/18/2005 7:50:34 A.M. Eastern Standard Time,
poulin.carrier@videotron.ca writes:
Hi Bill,
Sorry to take so long to respond. I had to make a
decision before i reply. I have choose to go with all steel pod. One of my
friend have access where he work to a rolling machine. So we will roll the
tube and I will use 5/8" steel plate as end caps. I will also place plates
inside the pods and fill the empty places around the battery with lead so
the pod will also serve as weight. To reduce over-all weight of the sub. Which
i want to keep at around 1000 pounds. the removable end-caps will be similar
to what Dan explain except that i will have 2 bolts and they will thread
directly on each side of the battery in a permanent side plate.
As for the battery, I presume that since my
battery have about 3/4" of air on the top, the plastic case will be under
pressure. And it may crack. I'm by no mean an expert but I'm still not
convinced about air-compensation the battery pod. I'll built a pod that can
bear the total pressure.
Yes i will compensate the motors. I'm using 2
minn-kota endura 30 motors. The only reason to compensate them is because of
the seal. The rest of the motor is capable, I think, to resist much pressure!
I will compensate them from the carbon tube directly. this tube will stay open
inside the cabine of the sub.
Thank you again for your much appreciated
input!
Pierre Poulin
Québec
Canada