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Re: [PSUBS-MAILIST] Two man sub on ebay (or buying used submarines)
Dave - thanks for that "newbie" reply regarding welds. I'm metallurgically
challenged, so it was a great intro.
Perhaps because of this limitation I'm a great fan of dry, ambient boats
using conventional boatbuilding techniques with a little bit of glass &
epoxy thrown in.
Here's a devil's advocate question for you: If this Kittredge sub does, in
fact, fail the weld exams, would there be any safe depth at all in which the
thing could operate? Say less than 3 atm.'s? Would the potential user be
able to kick around shallow reefs, etc.?
I imagine that would depend on the nature of the exam results. Maybe a
flower bed would be the safest bet.
Comments?
Rick
----- Original Message -----
From: "David Hahn" <delta531@yahoo.com>
To: <personal_submersibles@psubs.org>
Sent: Thursday, November 25, 2004 8:06 AM
Subject: Re: [PSUBS-MAILIST] Two man sub on ebay (or buying used submarines)
> Hi,
> First post from a newbie, but thought I might comment
> on the welding issues. I work at a powerplant, have
> some NDT certs (mag and PT), and am a CWI, as well as
> a boiler inspector, so have gotten to be a little
> familiar with some of these issues.
>
> I am not sure where you are, or if there are any NDT
> companies near you but if you can find a good
> ultrasound man you can find out a lot more about your
> welds then you can with xray. X-rays will show slag
> and porosity pretty well, and if you have a crack or
> delamination that runs the same direction as the beam
> it shows up pretty well, but we have had trouble with
> cracks that are 90 degs to the beam. A lot of both
> the UT (shearwave) and X-ray are in the
> interpetation, so the operator is really important.
>
> Actually, you could probably find out a lot about the
> welds if you had just a simple ultrasound d-meter.
> These are just depth meters and catch a sound bounce
> off of the back wall of the weld or piece of steel.
> Really uneven readings would indicate slag.
>
> But that would be sort of a half measure. In an
> industrial settting we would sandblast all the welds -
> interiour and exterior. A visual inspection would
> tell you if they back gouged the welds and made a good
> full penetration weld, or of they just gooped it over
> and (horrors) puttied it to make is smooth. A dye
> penetrant test would reveal pits, porosity, cracks
> etc, and a dye penetrant setup is cheap to buy and
> pretty much fool proof. It won't tell you what is
> inside a weld, but when you are talking about 1/4" to
> 3/8" thicknesses you can see most of the problems
> looking from either side. Pressure vessel
> manufacturing code would require x-rays on the
> longitudinal welds as well as the cirumferential
> welds. Some of that is probably for insurance
> purposes, and some for thicker-walled vessels.
>
> Sorry, I didn't mean to run on so long, and maybe
> everyone already is familiar with welding and NDE -
> don't mean to be a know-it-all (because I am a real
> newbie when pressure comes from the outside) but if I
> was going to climb into a sub that someone else had
> welded and I didn't know anything about it, I would
> sandblast it and run a dye penetrant test on all
> welds, inside and out. Bad spots would get ground
> out, retested to make sure that the defect was gone
> and carefully rewelded. These would be the minimum
> steps that I would take to ensure that the welding was
> done right, and that it wasn't likely to unzip.
>
> Best of luck,
>
> Dave
>
>
> --- "Dan H." <jmachine@adelphia.net> wrote:
>
> > Ian,
> > I hate to put a damper on your enthusiasm but!
> > I looked at the larger pic you sent and first off
> > the view ports don't look
> > right.
> >
> > The sub looks like a take off of a K design all
> > right but the builder took
> > many liberties. After reading Gene's look-see and
> > what I see in the larger
> > pic, you may not want it unless your only diving in
> > the shallows. The
> > trailer and tire issue you can deal with but not
> > being sure of the weld is a
> > bigger matter. You can have it X-rayed and repair
> > if needed but that's not
> > cheep.
> >
> > The bigger problem is with the view ports. From
> > what I see in the pic,
> > there isn't enough steel in the viewport housings.
> > They are thin and don't
> > have nearly enough surface to back up the lenses.
> > They look to be about a
> > eight inch lens size and need about an inch and a
> > half of back up all they
> > around the interior side of the lens. The hole on
> > the interior side of the
> > housing should be about six inches. You'd have to
> > change all of them to
> > ever take it to 250 feet.
> >
> > If you get it cheep enough, it may be good buy for
> > materials but already to
> > high priced for what you'd be getting.
> >
> > Sorrrry, Dan H.
> > ----- Original Message -----
> > From: "irox" <irox@ix.netcom.com>
> > To: <personal_submersibles@psubs.org>
> > Sent: Wednesday, November 24, 2004 6:02 PM
> > Subject: Re: [PSUBS-MAILIST] Two man sub on ebay (or
> > buying used submarines)
> >
> >
> > >
> > > Dan, thanks for the tips.
> > >
> > > Here is a bigger picture:
> > >
> >
> http://www.watercraft.gs/uploads/adphotos/a30p1553012798orig.jpg
> > >
> > > It seems to have a built in trailer, which while
> > interesting, isn't
> > something I'm
> > > really keen on. Atleast not on the implementation
> > in the picture. But it
> > does
> > > look like it could be easily removed with bolts.
> > Should I buy it I might
> > consider
> > > putting K350 style battery pods using the bolt
> > holes from the tailer bits.
> > >
> > > I'll pay close attention to the welds. The
> > welder/NDT talk from the first
> > > Psubs convention is coming back to me now (I'll
> > review the notes from
> > > that talk before I view the sub).
> > >
> > > The end-cap thickness tip is a good one. I might
> > beable to measure the
> > > thinkness through the main (down pointing) view
> > port (assuming it has
> > > one).
> > >
> > > From the picture is appears that the builder was
> > not planning on putting
> > > in a rear thruster (something I might change -
> > since I'm not planning on
> > > side thrusters).
> > >
> > > I'm not too keen on the MBTs either, but it's a
> > clever idea. According to
> > > the guys I talked with today, it's got plumming
> > and gauges inside, but
> > > they don't really know much about submarines.
> > >
> > > Thanks,
> > > Ian.
> > >
> > > -----Original Message-----
> > > From: "Dan H." <jmachine@adelphia.net>
> > > Sent: Nov 24, 2004 2:46 PM
> > > To: personal_submersibles@psubs.org
> > > Subject: Re: [PSUBS-MAILIST] Two man sub on ebay
> > (or buying used
> > submarines)
> > >
> > > Ian,
> > >
> > > It sure looks strange with the tires hanging off
> > of it but It's an idea.
> > > The pic is so small that it's difficult to see
> > much. One thing for sure,
> > it
> > > doesn't look much like the Lake Diver pic they're
> > using to sell it with.
> > > I'd say it's just about fraudulent to sell it with
> > that pic.
> > >
> > > Since there isn't any external battery pods I'd
> > say it's a deviation of a
> > > K-250 not K-350. I can't see if there's a rear
> > thruster. K-350 has a rear
> > > thruster. The hull ends are 3/8 thick on a K-350
> > and only 1/4 thick on a
> > > K-250 but you won't be able to measure it with out
> > drilling a hole.
> > >
> > > Since it's never seen water, rust shouldn't be an
> > issue. Just take a good
> > > look at the welds. Visual inspection isn't all
> > there is to it, but if
> > they
> > > look good, at least they might be good to the
> > root. Just look at the
> > > overall workmanship. If the builder spent the
> > time and made what you see
> > > look good, what you can't see is more likely to be
> > good as well.
> > >
> > > Is it plumbed for air and tank vents and wired for
> > power including fuses,
> > > lights and thru hulls? The e-bay add implies it
> > is. But they don't seem
> > to
> > > know much.
> > >
> > > If it's only a painted hull, it's about half done.
> > >
> > > Good luck, Dan H.
> > >
> > > ----- Original Message -----
> > > From: "irox" <irox@ix.netcom.com>
> > > To: <personal_submersibles@psubs.org>
> > > Sent: Wednesday, November 24, 2004 2:35 PM
> > > Subject: [PSUBS-MAILIST] Two man sub on ebay (or
> > buying used submarines)
> > >
> > >
> > > >
> > > > Hi,
> > > >
> > > > from talking with one of the current owners, I
> > think that it's this
> > > > submarine here:
> > > >
> >
> http://www.watercraft.gs/listing.php?main=Submersibles
> > > >
> > > > Unfortunately, the people who are selling it
> > didn't build it and don't
> > > know
> > > > anything about it. So I've been unable to ask
> > questions about the
> > origin
> > > > of the steel, fittings, pipes, qualitiy of the
> > welds, etc... They are
> > not
> > > sure
> > > > if it's a K350 or a K250 that's been modified.
> > Built in trailer,
> > > interesting,
> > > > but I'm not sure it'll stay that way if I own
> > it. It does appear to
> > have
> > > > internal battery box, everything else I know
> > > >
> > > > I'm going to try and see it as soon as possible.
> > > >
> > > > I think with subs getting more popullar we'll
> > need to write a guide
> > > > to buying used submarines.. ;-)
> > > >
> > > > Any tips (K250 vs K350 type differences,
> > mistakes to look for, etc.)
> > will
> > > > be most welcome.
> > > >
> > > > Thanks,
> > > > Ian.
> > > >
> > > >
> > > >
> > > >
> >
> ************************************************************************
> > > >
> >
> ************************************************************************
> > > >
> >
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> > with
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