Re: [PSUBS-MAILIST] Questions, questions and more questions

[TeslaTony@aol.com]

In a message dated 9/21/00 11:20:56 AM Pacific Daylight Time, 
MerlinSub@t-online.de writes:

>  Okay, some more answers, CSSX has to wait some days..
>  
>  No is not. But I am an engineer, and if you ask one of them anywere in
>  the world 
>  - he will/must/have to calculate a saftey factor. 
>  
>  2 years before I designed a small crane for a treasure salavage vessel
>  for a friend to hold the side-scan sonar and to lift some smaller
>  treasure. 
>  I told him : Its designed for a load of 0,8 ts and will have a destroy
>  load
>  of about 3,2 ts. Next question of him was : Can I use it to lift 1,6 ts
>  ? 
>  
>  CSSX is designed for a dive deep of 250 m ( 820 feet), the test deep
>  will be 310 m ( 1020 feet) and the destroy deep is around 500 m (1640
>  feet).
>  Some guys ask me : Will you dive 400 m (1310 feet)? 
>  My answers are : The load of the crane is 0,8 ts and CSSX will dive one 
>  time each year to 310 m - not more. 
>  
>  Civil submarines accidents shows two bigger problems : 
>  1.) Fire or smoke in the cabin
>  2.) Catching a net, cable, rope or wreck. 
>  
>  For problem 1.) a fire-extingusher, a battery main switch and a scuba
>  gear will help.
>  For problem 2.) Help comes from outside ... after two days. 

Okay, now I'm beginning to see the logic here, and why other subs are so 
heavy.

>  If you can - buy the book "No time of our side", or maybe Vance or Stan
>  will lend her
>  copys for some days. 

Okay, I'll check the library and see if they have it, if not then I can 
borrow it from someone who does.

>  > I've heard that waterjets get more efficient the faster they go, but are 
> they
>  > as efficient as a standard propeller at say.....2 knots?
>  
>  I don't know - but I think possible bad..
>  Karl and I played a wile with a Orca-wale-shape sub design with a
>  waterjet
>  main drive. But this sub was designed to win speed races with the
>  Orcas..

Maybe I'll just have to build a high performance sub sometime......

>  > Is there any specific number of times that I should be able to blow the
>  > ballast or should I just put the biggest tanks that I can fit onboard and
>  > have another extra one that has enough gas to take me to the surface 
once?
>  
>  You ask a me - so I look at the rules : 
>  
>  If you blow out your ballast-tanks (soft-tanks for surfcae bouancy and
>  freeboard only) 
>  with air it should be possible to blow them out 4 times (on the
>  surface). 
>  AND you regulator tank(s) (hard tanks to make your underwater bouancy to
>  "zero")
>  should be blow out 3 times at your working deep. 
>  
>  The air should be storage in two independant groups. 
>  In Sgt.Peppers I have two groups. One bottle is on the tank piping
>  system the other of the same
>  size on the scuba gear. There have both quick relase valves so I can
>  change both bottles if 
>  requiert. Ballast-tanks have a volume of 90 liters, both bottles have 
>  4 Liters with 225 bar = 2 x 4 x 225 = 1800 Liters / 90 Liters = 20 times
>  on the surface
>  Regulator-tank has 10 Liters with maximum dive of 150m so 
>  10 x 15 bar x 3 times needs 450 liter : 1800 / 450 = 4 x 3 = 12 times at
>  working deep. 
>  
>  According to the rules : 1800 - 450 = 1350 Liter / 90 Liter = 15 times -
>  that means I can blow out the regulator tanks 3 times at working deep
>  and 15 times on the surface
>  
>  Also intressting (not for the rules) is how often you can blow you
>  regulator- AND your ballast- tanks 
>  at the working-deep : here 150 m (equal to 15 bar ) needs : 
>  (10 liter  + 90 liter) x 15 bar = 1500 liter . 1800/1500 = 1,2 times..
>  The forces of positive bouancy is than 100 liter (equal 100 kg or 220
>  lb) - 
>  that will -maybe- destroy the small fishing-rope that catched your
>  propeller. If not the 
>  drop weight will give additional 200 lb - if not the 76 hours of oxygen
>  will
>  help to give you friends time to find the sub and cut the rope..
>  
>  An accident is normaly not only one big error - its an addition of small
>  errors and mistakes.

The biggest drawback of blowing the tanks with the propeller stuck in 
something would be that the propeller and maybe even the motor could get 
severely damaged, although that isn't anywhere near as bad as being stuck on 
the ocean floor for two days.

>  > Sounds fair enough, although I don't think CSSX will be transported on a
>  > trailer behind a pickup.
>  
>  CSSX can be dismounted to three parts : The sail, the stern including 
>  the machinery space and the forward body with the bow. The beam, length
>  and high of this parts make it possible to carry it on two trucks all
>  over europe. Its for example less expensive and much quicker to travel 
>  the sub in this parts from the North Sea to the Mediterranean this way..
>  The bolted frame is in the machinery space just behind the
>  diver-chamber,
>  so it is also easy to refit or change bigger parts like the diesel. 

Sounds like what they were going to do with the Colombian sub, split it up 
into three peices and transport it overland. You didn't happen to have taken 
a vacation to someplace in south america recently have you?

>  > I wonder if stainless would be worth the extra money if it lasts longer 
> than
>  > other steels.
>  
>  Not for the main body - also it not so easy to handle (welding,
>  drilling) 
>  as normal steel. On CSSX some parts made from stainless steel. 
>  For example the frames of the superstructure - because they are
>  difficult
>  to repaint. Also the shaft of the acrylic periscop mast and all the
>  rings 
>  were the rubber of the hatches closed - because bad painting or
>  corrosion
>  here will be prefent the rubber from sealing. 

The nice thing about stainless is that it wouldn't have to be painted to keep 
it from rusting since it won't rust.

>  > I was figuring 150 feet, although if the materials can take it I might
>  > increase it to 250 or even 300 feet.
>  
>  Okay. But if it dives deeper than a diver you can earn someday maybe
>  some money..
>  A normal sport diver can dive 160 feet..

Hmmm, then maybe I should go for 250 feet instead....

>  > I want something that can be opened from the inside and outside, in case 
> the
>  > operator (usually me) needs to be rescued, could there be some kind of
>  > bolting system?
>  > 
>  
>  Nobody can open your sub in the deep from outside. The pressure
>  differntial between 
>  inside and outside will prevent that. Help from outside in the deep will
>  raise
>  your small boat. But it helps if you on the surface and you lungs are
>  filled with
>  smoke or other exhaust...

I don't think I would want to bail out at a depth where the dome can't be 
removed anyways.

>  > Ouch, 5000 dollars is more than I want to spend on the entire sub!
>  
>  Look - most people build only one sub in their live. If you build it
>  from 
>  old material or in any other way in poor design - because out of money 
>  - you waste.. all the money and all the time. I know some (many..)
>  of this kind of private sub - they dive 1 -12 dives more or less and 
>  ended than in the forward garden ..
>  The last refit on Sgt.Peppers was 2000 Dollar - only the refit ! 
>  
>  Make a pre-calculation of the estimate cost for your sub.
>  Don't forget the pressure hull with the frames, the dome, the batteries,
>  the cables
>  the engines, the scuba gear, the trailer, the big pickup, the battery
>  charger, 
>  the vales, pipes, radio, compas, joystick control, seat, helm, windows, 
>  the live-support system, pressure bottles, indicators, switches, 
>  the working tools, the place to rent in the hangar, 
>  the time to rent a welding- profi or some other experts you need. 
>  
>  If you have made this calculation - calculate 1.5 times higher.. thats
>  the price 
>  you have to pay.  
>  
>  May ask Dale for the actuell price for his sub. I think 7500 Dollar is
>  the 
>  absolut minimum for a  u.s.e.f.u.l one seater. May about 15% more for a
>  double seater. 
>  A real design starts with about 15.000 Dollar. 

Still, $4000 is more than any other bit of equipment on the sub and I don't 
think that the truck will cost that much either (maybe it will, but my family 
is pretty good at finding good deals on vehicles).

>  > Eight small motors should do the job rather nicely then, now all I have 
to 
> do
>  > is find the right size.....
>  
>  Eight seams to much - two seems the minimum and more than fife makes no
>  sence (for me). 
>  If two small engines have the same job - use one bigger. Easier to build
>  and not so
>  expensive. And in some cases - less parts - more save. 

Actually I was thinking of ten motors, two for main propulsion and another 
eight in a cross configuration on the front and back (four front, four back) 
for finer control and stabilization.

>  > I think that Ferrellgas has a 10ft. by 3.5ft. tank used at gas stations 
or
>  > other refilling stations, which would be perfect for me unless buying 
some
>  > pipe and some endcaps are cheaper.
>  
>  3,5 square x 3,1415 / 4 x 10 = 2,3 t displacement for the hull, 
>  about 2,7 - 3 ts for the hole boat.

Wow, size certainly adds up a lot of displacement fast.

>  > Wow, if putting in two or three ribs will increase my dive depth then I 
> might
>  > as well put them in even if only for safety.
>  
>  Add to you gas-tank the cost to cut the tank in two parts to put the
>  rings 
>  and the equipment in. If you not cut it - okay add the building time
>  with 
>  a factor of 1,5 to 2 ... And use a gas-mask or scuba gear if you want to 
>  welding something inside..

Maybe the propane tank isn't looking so good after all........

>  Everthing I told here is my private opinion - you use this information
>  at your own risk.
>  (This sentence was for my insurance company.)
>  
>  Best regards - Carsten 
>  And do it right - or don't do it.

Insurance companies can be a bit of a pain at times, and I intend to do the 
whole thing right the first time so I don't learn about an interesting 
phenomena called "implosions".

Thanks for your help,
Anthony