I had one of the the Nekton Deltas for a few years that Doug Privett built and I believe the diameter was around 8 inches but I'm not sure. However, I never liked the idea of drilling holes in the view ports to use bolts to hold it in place. I know it works and that at one time it was an ABS approved method but it just seemed like a problem searching for a location to happen. I thought it would have been just as easy to build a flange that would hold the view port and keep the bolts to the out side of the fixture. If you decide to drill your own holes in the Acrylic, you may want to hand the project for cutting the view ports over to some one that has a water jet machine. They can cut out the holes and you won't be scared to have a nice piece of Acrylic crack. If you decide to drill your own holes make sure your drill is sharpened for Acrylic. Take an ordinary drill and grind it to a very pointy taper like a arrow tip used
for target practice. If you use a standard cut drill, it will grab in and crack the View port. Keep it cool and wet with water as you drill through it and practice on a scrap piece first. Like Mr. Nuytten has indicated the view ports where around an inch thick. The gaskets I used where made from a cork material that was impregnated with Neoprene. I always bought them pre-cut from a gasket manufacture out in Houston, but I don't remember what the name of the company was. Once and a while after servicing a view port it would leak just a few drops until the sub reached a few atmospheres of pressure and then they would stop dripping. They never actually squirted mind you, but just a few drips then they'd stop. I never wanted to tighten the bolts to much if you know what I mean. I still flinch a little when I remember taking a straight edge and setting it against the view port at depth. At depth it does start
to flex inward just a little, and you can measure it. I had planed on changing all the ports with 1.25 or 1.5 inch acrylic but as things go, the paper work for the ABS would have been to much trouble. It never ceases to amaze me how pressure vessels change shape at depth. It blew me away when Mr Nuytten said that Deep Rover lost around 40 or 50 pounds buoyancy at depth, I don't remember the exact number he said but I just shook my head in amazement. That just seems so crazy to me but I understand it.
Dave Banks
Phil Nuytten <pnuytten@compuserve.com> wrote:
Ben:
It is, of course, a question of diameter versus the onch inch
thickness. For a very rough idea, check out the 'Delta' sub - they have a
good website ( not particularly complimentary to our ''DeepWorkers" - but
we always turn the other cheek . . . coff, coff.). Google >delta
submersible< The other Doug Privett-designed Nektons in the series had
one inch thick ports and the boats were rated for a thousand feet! Check
Busby to see the diameters.
Phil Nuytten.
************************************************************************
************************************************************************
************************************************************************
The personal submersibles mailing list complies with the US Federal
CAN-SPAM Act of 2003. Your email address appears in our database
because either
you, or someone you know, requested you receive messages
from our organization.
If you want to be removed from this mailing list simply click on the
link below or send a blank email message to:
removeme-personal_submersibles@psubs.org
Removal of your email address from this mailing list occurs by an
automated process and should be complete within five minutes of
our server receiving your request.
PSUBS.ORG
PO Box 311
Weare, NH 03281
603-529-1100
************************************************************************
************************************************************************
************************************************************************