Re: [PSUBS-MAILIST] newbee

["Captain Nemo" <vulcania@interpac.net>]

----- Original Message -----
From: "Rob Divine" <divine@kconline.com>


"1.  Captain Nemo, you have the most ratical design of all I have seen
(other than on the movie on wich you took the insparation frome)."

Hi Rob, and welcome.

The Disney NAUTILUS is indeed a very radical design; but the design of my
NAUTILUS MINISUB is even moreso.  In my case, "what you see is NOT what you
get".  My submarine only looks like the Disney design on the outside;
inside, it's completely different.  For example, the pressure hull (that
part which actually withstands depth pressure) is a machine-formed steel
teardrop-spindle: a shape chosen for modern nuke subs because of it's
combined qualities of pressure-resistant strength and hydrodynamic
efficiency.  So, (hull-wise, anyway) while it might outwardly look
"radical", internally my submarine is based on concepts that are fairly well
established.

"How deep is you sub cabable of going?"

Although, as nearly as I can estimate, the hull wouldn't actually fail until
reaching much greater depths, I've established my depth limit at 100 Feet
Sea Water, but won't intentionally take it any deeper than 33 FSW, or
operate in water deeper than 50 feet.  This is strictly an experimental
recreational boat, built for fun,  (and also because nobody had built a
functional Disney NAUTILUS before).

I was forced to remain within limitations imposed by the visual appearance
of the Disney design, so in some ways (in terms of functionality), my
MINISUB is not a very good sub at all (she's got less than one foot of
freeboard, for example).  However, other aspects (like the hydrobatic
ballast system) are in some ways better than I've seen on other subs.  But
most importantly, it's a HOMEBUILT; and in my opinion, one should never
operate a homebuilt submarine at depths beyond which he can safely escape;
but more about that in a moment.

"I have desided on building it out of steel, but all the talk of pressure
and the proper design to handle hull pressure has me
conserned."

When you say you "have decided on building it" I do hope you aren't talking
about replicating my NAUTILUS MINISUB.  There is a lot more to this design
than meets the eye; submarines are one of those things where what you don't
know CAN hurt you; and if you're thinking about copying what I've done based
on what's been published about the project, I must strongly recommend that
you do not.  I say this for the sake of your own safety.

It's good that you are concerned; I think that's a healthy attitude.
(Again, in my opinion) the first thing a prospective sub builder should
realize is that submarines are inherently dangerous.  Hopefully, that
awareness will keep one from exceeding his own limitations.

" 2.  What gauge of steel is recomended?  I only plan to go to about 50ft
max.  I live in an county that has 114 lakes and I dont plan on ever taking
it to deep water."

There is no simple answer to that question.  The required thickness of your
hull material (in terms of depth-pressure resistance) depends on a lot of
variables, including: (1) the type of steel used; (2) the size and shape of
your pressure hull; (3) the use (or absence) of reinforcements; and much
more.  Some say design parameters can be generally determined
mathematically; but then again, there are examples I could point to where
hulls that looked good in terms of "the numbers" failed in actual use.  You
might study what others have done, see what has already been proven
reasonably reliable at a given depth; and experiment with that before ever
committing the safety of a human being to your design; but even then it will
only be "safe" to a certain degree short of "completely".

"3.  In 50ft of water is the pressure so great that I need to be verry
concerned of hull pressure?"

Be concerned.  Be very, VERY concerned.  (If you think 50 feet is shallow,
consider how well you can breathe while completely submerged at a depth of
one inch without some form of SCUBA or snorkel.)

Regarding  pressure on your hull: with one atmosphere (say, about 14.8
pounds per square inch) inside; at 50 FSW, the pressure hull is withstanding
an additional uncompensated force of about 22.4 PSI; that's about 3,225.6
pounds  per square foot.  Now, visualize a one-foot square piece of steel
plate, somehow being propelled by more than 1.5 tons of water pressure:
would you want to be in the path of such a missile?  I wouldn't.  So yes;
there is every reason to be concerned about the quality of design and
construction, even though we intentionally operate at "only" 50 feet.

"I have lots more questions, and as construction goes onward Im shure ill
have many more. Remember Im a newbee, so dont be to hard on me as to the
simplisity of my questions."

People on this site like to talk submarines; myself included.  We're
interested in them.  This is one means by which we exchange information; and
how the Worldwide pool of knowledge regarding  personal subs is growing.
Hopefully, part of our  intent here is to enhance public awareness and
public safety.  Having said that, I'll say this:

In my opinion, homebuilt subs aren't something one should just jump into;
mine was the result of more than 30 years of other related involvements
which lead up to it.  I think one should  study everything he can find about
underwater technologies; and experiment in safe ways with design concepts;
before he ever thinks about building and/or operating a personal submarine.
Those who decide to proceed do so at their own considerable risk.

Even when they are designed, constructed, and operated to the best of man's
abilities, submarines are still inherently dangerous.  Subs are complex
self-contained vehicles that carry people through hostile environments where
failure can have catastrophic results.  Therefore, submarines have
traditionally been the product of the best of man's capabilities: designed
by professionals; manufactured to the highest possible standards using
state-of-the-art tools and facilities; and operated by trained and
experienced pilots.

Today, the aforementioned (and wise) traditions are being challenged by
backyard mechanics (like myself) who wish to experiment with submarines, and
take it upon ourselves to build our own.  (In my own particular case, I do
so because my desire to learn will not be held back by a lack of funding or
manufacturing facilities.)  The fact that subs like mine (and others) exist
is proof that it can be done; but I don't want anyone to think I believe it
can be done with complete safety.  We're operating on dangerous ground here;
oftentimes dealing with unproven methods,  and taking calculated risks.
This is all very much experimental, and should never be thought of as
entirely "safe".

My sub works because I  (1) took the time to study, learn, and experiment
with related technologies before ever thinking about building a submarine;
(2) used knowledge of other, proven submarines to design mine to be much
stronger than I figured it needed to be at the depths we'd be operating  in;
and (3) intentionally limit myself to operating in conditions which are far
less severe than I believe the boat can withstand.  Even then I don't ever
consider myself as being "safe"; and while I am willing to take risks
myself, I would not think of taking a passenger down with me, even though my
NAUTILUS MINISUB is designed to carry the weight of one.

The best deep submergence vehicles in the World are designed by certified
engineers, and built using the finest materials and facilities available.
Even so, some components for these vehicles have been known to fail at
embarrassingly shallow depths.  Of course, I understand acceptable levels of
safety can be maintained by testing these components individually before
installing them in a manned system; but even so, submarines are complicated
concatenations of components combined to cooperate under copiously complex
conditions (that was fun!) ; and while it is possible to achieve very high
degrees of reliability using state-of-the-art means,  "absolute assured
safety" at depth doesn't exist at this point in the development of
underwater technologies, any more than it does in other vehicles intended
for use under extreme conditions.

Now, if such is the case for "the pros", imagine what it's like for the
"little guy" building a sub in his backyard or garage, where he is limited
in tooling, and there are oftentimes less (if any) controls over quality.
Thus, homebuilt submarines are risky any way you look at it; some may be
better than others, but none are entirely reliable.  I think one should
realize this from the start.

(Here it comes.)  I've built vehicles ranging from skateboards to aircraft;
survived the barnstorming "equipment-development" days of sport parachuting;
built quite a few experimental prototypes I can't disclose here; and
blah-blah-blah, etc.  I'm not trying to engrandize my own ego here, only
trying to point out that these endeavors have all involved taking calculated
risks; and the fact that I'm still alive is proof that one can frequently
get away with it, IF he factors in a reasonable margin of safety.  But
"calculated risk" implies the ever-present possibility that, someday, the
odds will catch up to you.  When you are dealing with experimentation, you
deal with unknowns that can produce unpredicted results.  I have always
understood and accepted that risk.  But can I recommend that anyone else do
the same?  No.

I'm not trying to scare anyone off, but the fact is, when somebody with no
prior experience comes to me and says he wants to build a submarine, my
first reaction is to tell him to forget it, because I know it's a
deceptively complex endeavor, and what the potential penalty for failure
might be.  Nevertheless, more and more people are learning  to do it every
day, all around the World.  So,  I and others offer what we've learned about
the subject, in the hope that doing so will enhance safety in a growing
public involvement that seemingly will continue whether we participate in it
or not.

You have questions; we can try our best to answer in the interest of being
of some help.  But you must take it upon yourself to learn all you can,  and
accept full responsibility for what you do with that knowledge.  Those are
the rules we all have to live by.

" Thank you so much for having this forum."

Yes, we're all thankful to Ray and Jon for making this possible.

" PS: Do your wifes think your nuts also?"

I don't think so.  But then again, in the almost 20 years we've been
together, she's flown airplanes I've built; jumped with a parachute from an
airplane I flew and under the supervision of a jumpmaster I helped certify;
tested experimental rebreathers I designed and built; been my chief
crewmember during tests of my submarine projects; spent many an hour aboard
my radical Harley chopper; surfed and became SCUBA certified in "The Red
Triangle"; grabbed sharks by the tail at 120 feet outside Molokini Crater;
and endured my electric guitar playing, among other things.  After doing all
that, if she thinks I'm nuts, what would that make her?   ;-)

Very best regards,

Pat Regan
vulcania@interpac.net