Re: [PSUBS-MAILIST] Newbee to psubs...

[MerlinSub@t-online.de (Carsten Standfuß)]

Sorry John - I did a mistake with the pound weights...
Anchor should be 100 Kg or : 220 pound
lost weight and volume of on e diver leave inside is about 
80 kg or 180 pound..

Carsten


Carsten Standfuß schrieb:
> 
> Hi John, Carsten here from Germany, my answers between your lines.
> 
> "John R. Farrington" schrieb:
> >
> > Hi all,
> >
> > Just wanted to take a few moments to introduce myself.
> > I've been lurking on the list for a little while, and
> > interested in psubs for quite a number of years now.
> >
> > I'd exchanged some mail with a guy named Matt Hunsaker
> > about 6 years ago and he'd given me some interesting
> > info on a sub of his, a Sportsman 300.  That kinda
> > got me interested in psubs, but I pretty much shelved
> > the idea until now.
> >
> > I've been digging through the archives to start becoming
> > more familiar with psubs, and to start getting a grasp
> > on what is involved in building one.
> >
> > I'm in contact with Vance concerning the Kittredge plans
> > and now have a few more general questions that I thought
> > I'd pose to the group.
> >
> > With respect to psub certification:
> >
> >   It appears that psub certification is very valuable.
> >   Any idea if most psubs that are out there are actually
> >   certified, or do most people just do away with having
> >   them certified?
> 
> During assembling the Sgt.Peppers I bought a Certification book
> from the GL (Germanischer Lloyd) with is simillar to ABS.
> The hole sub as is is now without certification had cost
> for material of about 10.000 Dollar.
> The tank test witch is nessesary for certification cost
> about 25.000 Dollar a day plus the incurance company for the
> navy tank test Chamber also 25.000 Dollar.
> Every vale with a certification mark on it will cost about 2-10 times
> the price of one without.
> (I have worked in a factory for brass parts - make the factory test
> mark on each 1 of 10 vales - its the same vales like the other without
> marks..)
> Certification is useful if you want to insurance your sub, or for
> tourist sub, or sub with a commercial crew or commerical operation.
> For private use it is normaly to expensive.
> But buy the book and build the sub according to the rules.
> 
> >
> >   I do have welding experience, but have no license or
> >   welding certification of that sort.  If I do my own
> >   welding on the pressure hull, is the hull still
> >   certifyable if it passes the appropriate depth tests?
> 
> No..its not. You need certification for the steel, for the welder,
> the electrodes and also xrays testing..
> 
> I am also a experince welder without licence - but all pressure
> parts (pressure hull) on my sub are made from a professional.
> All outside and inside weelding made by myself. It is not so expensive
> it looks like. The pressure hull has normaly not so much welding-areas.
> One longitudinal, two cyles and one or two for the tower.
> For my next sub I will go the same way.. with pressure hull weldings
> made from a robot control welding machine.
> >
> >   The sub that I'd be building would likely be of the
> >   Kittredge variety, I believe rated to a depth of 250
> >   feet.  This means it should be tested to 500 feet or so.
> >   I live in Austin TX, which doesn't have any 500 foot
> >   deep lakes around.  When others pressure test their
> >   subs, do they typically trailer them down to the ocean,
> >   hire a boat with some sort of crane/winch mechanism,
> >   haul the sub into deep water, then do a number of
> >   plunges with the sub to the test depth?
> >   (BTW, if anyone owns a sub, and lives in central TX,
> >    I'd be interested in seeing the sub in person)
> 
> And if you sit/lay inside you will find out why it has flooded..
> I did it in this way but never reach test dive - the lakes here
> are really shallow..
> 
> >
> > The sub that I build would probably do 99% of its
> > dives in the local lakes, which usually have a visibility
> > of 15-20 feet, or less.  Sometimes 5 feet or less in some
> > areas.  Because of the limited visibility, I've got big
> > concerns about getting the sub tangled in someone's old
> > anchor line, or whatever may be lurking on the bottom.
> >
> > Has anyone out there had any serious incidents involving
> > entanglement?  Ever had to abandon because of entanglement?
> >
> 
> I have not - but it helps if all engines are protected and
> inside the streamline hull - without arms , lights, thruister
> etc. outside.
> I can drop my both front thruster if a rope is inside
> and also the main battery keel.
> 
> > I'd like to be able to get out of the sub, clear the
> > entanglement, and get back in, without having to flood
> > the sub.  Anybody have a sub with a hatch on the bottom
> > as well as on the top?  ie: Raise the air pressure in
> > the sub to ambient, exit with scuba gear, clear the
> > entanglement, climb back in, head to surface, bleeding
> > off extra pressure on ascent. (keeping in mind all
> > nitrogen-related issues)
> 
> I have made a drawing concept for this kind of vessel
> with a hutch on the bottom between two drivers.
> But you need a 50 pound anchor or a landing gear and additional
> 50 pound in your regulator tanks. If you leave a so small
> sub the inside lost the volume and weight of your body.
> So with your body goes out the same amount of water gets in - or
> if you have an automatic to level the waterline in the hutchpipe -
> the sub will fly away because of the loss of 40 pounds weight.
> Also some small implosions of all your TV screens and other
> close parts..
> >
> > A K-250 has an approx. volume of 40 cubic ft from what
> > I can tell.  So one full scuba tank would get you
> > an additional 2 atm inside the sub, which is about
> > 65ft of water.  I'd need 2 full tanks to be able to
> > exit the sub at 125 feet, three would get me over
> > 180ft, (max lake depth is around 160), but at that
> > depth, I don't think I'd really have the time
> > (decompression-wise), to fill the sub, get out, clear
> > an entanglement, get back in, and get the sub to
> > shallow water before taking on too much nitrogen.
> 
> You can use helium to fill the sub..
> >
> > (sorry for being long-winded)  ;-)
> >
> > But maybe at 50ft I could get out and back in.
> >
> > The idea is to save the sub, without flooding it.
> > Or, are my efforts better spent building the sub such
> > that flooding it damages as little as possible?
> 
> That is a new - and maybe good idear. Most part of my
> electronic like echosounder, radio etc and also the
> Live Support System will be ready for a scrapp-place
> after flooding in salt water. But if you protected all
> this stuff - thats will be maybe more expensive as to buy new one..
> 
> In fresh water and with all electronic-platines covered with
> clear-painting and the battery main switch offline- maybe that helps.
> 
> I dumped a car in salt water during trailer my motorboat some
> years before. I removed it from the water after 5 minutes, lost the
> radio two minutes later, cleaned it with high pressure frehwater the
> same days, lost the lamps after two days, the servo stearing
> contol after two weeks, the starter after 3 and the breaks after 4..
> It was not my car..
> 
> >
> > I'm still trying to decide if building one of these
> > would be worth it, knowing all of the risks, as well
> > as knowing that my primary dive opportunities will
> > just be in a lake.
> 
> Build a boat for at minimum two persons is a good idear.
> 
> Carsten
> 
> >
> > Sure sounds like fun though!
> >
> > Thanks for any advice.
> >
> > -John Farrington