Re: [PSUBS-MAILIST] hatch rings

["Adam Lawrence" <adteleka@in-tch.com>]

Weld a stainless overlay on both surfaces and then machine them.

Adam



----- Original Message ----- 
From: "Dan H." <jmachine@adelphia.net>
To: <personal_submersibles@psubs.org>
Sent: Thursday, April 08, 2004 6:18 AM
Subject: Re: [PSUBS-MAILIST] hatch rings


> Brian,
>
> Your hatch cover being stainless isn't as important as the hatch ring it
> mates to.  Your most likely going to be placing your O-ring groove in the
> hatch cover and it will stay there.  You can make that part out of carbon
> steel and paint it.  True, stainless would be better, but as you mentioned
> it's pricey.  Your $156 dollar ring would be over $400 in stainless.
>
> The mating ring, conning tower top, is much better in stainless since it's
> what your going to be stepping on and dragging things in and out over.
> Paint will get scratched there and cause you problems.  Also the O-ring
has
> to make a good seal on it every time you close the hatch.
>
> If your watching you budget, stay with the carbon steel ring you have
> already ordered but do order a stainless ring for the top of your conning
> tower.  One note, when machining the O-ring groove don't forget to allow a
> few thousants on each surface for paint build up.
>
> Dan H.
> ----- Original Message -----
> From: "Brian Cox" <ojaibees@ojai.net>
> To: <personal_submersibles@psubs.org>
> Sent: Thursday, April 08, 2004 12:34 AM
> Subject: Re: [PSUBS-MAILIST] hatch rings
>
>
> > I think I may have made an error when designing this hatch.  My plan was
> to build just the hatch and then seal off the bottom part and then take
off
> our coast here and drop it down to about 1200' or( 365 meters) to see if
it
> would hold together.  I'm mainly curious about the acrylic dounut.
> Origionally I was thinking that the whole assembly would be the hatch but
> upon further thought that seemed like it would be too heavy to handle so I
> decided to split the hatch above the acrylic dounut so just the top steel
> hemisphere would open.  This is the drawing I posted a while back
> http://www.prismnet.com/~moki/20040309.103505/hatchXdrawing.jpg  .  The
> bummer part is that I just ordered a ring 24" OD by 20" ID and .75 thick
> A516 - 70  which I was planning to weld onto the 20" (508mm) hemisphere.
> Since when that ring gets welded onto the hemisphere there is going to be
a
> lot of warping of the ring and it will have to be machined flat so it
seems
> like you would need enough metal so!
> >   that once you're done machining it is still thick enough to be strong.
> If I had to use stainless steel for that ring I bet that would be really
> expensive.  The 24" od  by  20" id  by .75" thick is going to run me
$156.00
> would it be possible to weld a piece of 1/4" stainless onto the thicker
> piece or would you still have the problem of warping ?
> >
> > Brian
> > ----- Original Message -----
> > From: "Carsten Standfuss" <MerlinSub@t-online.de>
> > To: <personal_submersibles@psubs.org>
> > Sent: Wednesday, April 07, 2004 2:06 PM
> > Subject: Re: [PSUBS-MAILIST] hatch rings
> >
> >
> > > I would say: Yes.
> > >
> > > In the year 2004 hatches rings and troughull connetors should be made
> > > from stainless steel. Corrosion on this parts can be really expensive
> > > over the years. Maintance time is also an issue.
> > >
> > > regards Carsten
> > >
> > > > Brian Cox schrieb:
> > > >
> > > > Do the hatch rings need to be stainless
> > >
> > >
> >
> >
> >
>