One air supply tank makes plumbing and operation simpler. The issue
shouldn't be number of tanks but volume of air required for the number of
dives you want to perform before having to refill. I personally like the
solution JimK took with Bionic Guppy putting an industrial sized air
cylinder on the outside of the hull. Easy to get on/off and a large
capacity of air available. The advantage of a manifold is that you can
group all your in/out valves in one place instead of having them all over
the cabin. George's ballast/vent plan is simple, but requires many
valves. I'd love to see a manifold system with a double throw valve so
that you push ONE valve forward and it vents, push that same valve
rearward and it blows, no air flow in the center position. That would cut
down on the number of valves and plumbing required.
You are correct that the VBT 1/2 inch pipe acts as both "blow" and "vent".
I can't explain the dual valves on the VBT vent pipe in front of the CT,
but certainly George didn't use it on the K600...see link below that shows
the VBT vent (at top on photo) with only one valve on it.
http://www.psubs.org/projects/common/scripts/display/bigpic.cgi/projects/1234567801/k-600submarine/37.jpg
You're a pretty slim guy, as was Kittredge, but for chunkers like myself I
find the layout of both the VBT and emergency drop weights to be
ill-conceived due to the fact you have to reach behind you to get access
to the valves and releases to work them. A skinny guy can turn around
easily enough inside but not us big guys. We have to reach behind blindly
and then we don't have the same torque or force available as if we were
facing the valve. I plan on changing the K600 VBT and may take Alec's
approach and do away with it completely relying on calculating payload and
offsetting by adding/removing weights. I also plan on redesigning the
drop weight release. Unfortunately I haven't gotten that far yet so
haven't considered alternatives.
I think George did a great job with the K-boat designs BUT that he
designed them with himself as a model. George probably never weighed more
than 140 lbs at his all time highest and could easily contort himself
in/out/around the cabin, but for physically larger folks it is tough to
do, not to mention if you have a sore arm or leg. I would not hesitate to
rearrange things that make more sense or make it easier for YOU to pilot
your vessel.
Jon
On 11/29/2011 12:43 PM, James Frankland wrote:
Hi all,
Im almost finished painting my sub. What a chore. Still, it looks good
to finally see it taking shape. Anyway, after that im onto the pipework
and i'd like to ask people's advice\opinon.
This is of course the K350 design page 013 on the standard plans.
The plans show only 1 scuba tank connected to blow all 3 tanks. I was
under the impression that most people carried at least 2. I was thinking
of modifying the setup to have 2 tanks, 1 to blow aft and variable tank
and 1 for forward.
Am i right in assuming the VBT 1\2 inch pipe also serves as a vent?
On the variable vent pipe where it exits the sub forward of the tower,
why are there 2 identical valves? I assume 1 is to operate normally,
and the other as the emergency shut off connected directly to the pipe
nipple? Same with the depth gauge? (Which i dont have incidentally).
Anyway, is this configuration the best way to go about things? Are there
any alternatives that people have used that may be better? Im going to
use the swagelock system and will of course use SS instead of copper as
it calls for.
I notice snoopy has some sort of machined manifold. Maybe this is
better?
Any suggestions from people before i pick up the phone to swagelock?
Kind Regards
James
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