Re: [PSUBS-MAILIST] Hatch design

["Karl Fuller" <fullerk@voyager.co.nz>]

Does anybody know if the plexiglass (acylic ?) domes can be made/able to be
made or exist, with the flange constructed so that it faces inwards ? This
would enable the ability to futher streamline the design, reducing drag due
to shape. (I imagine it could be done if the inner flange, was made parallel
to the centre line until it ran out, so the mandral could be withdrawn.)
This appeared to have been done on a soon to launched, white, very
streamlined sub I saw on TV recently, which no one seems to have mentioned.
It was being built by a wealthy client and I only saw the end of the item
and only caught the end. Anyone know any details ?
----- Original Message -----
From: Dale <heinzind@cadvision.com>
To: <personal_submersibles@psubs.org>
Sent: 19 July 2000 11:13
Subject: Re: [PSUBS-MAILIST] Hatch design


>
> -----Original Message-----
> From: VBra676539@aol.com <VBra676539@aol.com>
> To: personal_submersibles@psubs.org <personal_submersibles@psubs.org>
> Date: Tuesday, July 18, 2000 1:14 PM
> Subject: Re: [PSUBS-MAILIST] Hatch design
>
>
> >Herman,
> >
> >The dome hatch on Captain Kittredge's K-250 design is rated for an
> operating depth of 250 feet. It is plexiglas, which has much healthier
> characteristics under pressure than lexan, and cost, the last I heard,
about
> $800 US. They can be ordered from a fabricator in Maryland, recommended by
> the designer.
> >
> >One of the early K-250s was tested in a tank to destruction. Captain
> Kittredge had calculated that the dome would be the first thing to go, and
> it was. At 800-plus feet!!! Still, to be conservative, he has limited the
> designed operating depth to 250 feet. If you want to go deeper, you will
> need to redesign with thicker material (the K250 is made from one inch
> material) or go Kittredge's K-350 design route, which gives you an all
steel
> conning tower with four viewports in the cylinder and one in the hatch.
The
> K-350 tests to 500 feet unmanned to verify strength and operability. I am
> not sure what is called for to test the K-250.
> >
> >The dome builder could probably fabricate whatever you wanted, and if you
> had someone on tap to redesign the retaining ring structure you could
> probably go deeper with a heavy duty version on the K-250.
> >
> >Diving to 100 meters off Malta sounds very good indeed, although you
might
> think the same of my backyard on the Treasure Coast of Florida, or the
Keys,
> 2 hours away. Or how about a psub rodeo in Hawaii? We've got a connection
> out there. I wonder what the airlines would say about our excess luggage?
I
> can see it now. "Say, young feller, how much does that big box weigh?"
> Psubber replies (sheepishly): "....er....2 tons, sir. Is that over the
carry
> on limit?"
> >
> >Best Regards,
> >Vance Bradley
> >
>
> I bought the acrylic dome , and it was $800.00 US. ( you remembered
> exactally Vance!!!)   The one I have is made from 1.25 inch thick
material,
> the plans call for 1 inch material...  as for testing the sub, George
> recomended that I drop the K250 down to 500 feet, for 1 hr, ( unmanned)
and
> he said when I pull it up, to use it confidently to 250 feet..I also just
> purchased the flat 16" viewport, and it was $275.00 US.  The one I got is
> 2.5 inches thick, instead of the 2inch one called for.  Interesting note
> here is that the dome failed within 2% of where George figured it
would..he
> has done his homework on his subs..!!  The name and phone number of the
> supplier is on the archives , if you are interested,and cannot find it,  I
> still have it (somewhere), and can give them again.  He can make up just
> about anything you want.  We have discussed domes as big as 36 inches.  As
> for the retaining ring, I had mine machined out of a solid 2" thick piece
of
> material, both for stregnth, and because I could not get the other ones to
> not warp when welding.. I have not inquired what the failure depth would
be
> on the ring, but if it is like everything else on this sub, it will be
very
> overbilt.
>
>
>    dale..
> by the way, does any one have an idea for an extendable toung on a
trailer??
>
> dale.
>
>
>