[PSUBS-MAILIST] conical port seal

Thu Jul 28 05:28:21 EDT 2016

Hi Hank.

I remember going over this when I did my hatch port.  Similar although not
to the same spec as yours.  The viewport was made by Stanley Plastics and
there was a very small "flat" on the high pressure edge.  Not a chamfer as
such, just a flat bit.  So I used this small gap to put an O ring in and
then put an epdm gasket between the steel retaining ring and port.  Took up
the space on the seat side with a cork gasket.  It seems to work ok
although I haven't tested it to any great pressure.   Hope pic makes it
through.

On 28 July 2016 at 04:14, hank pronk via Personal_Submersibles <
personal_submersibles at psubs.org> wrote:

> Okay, I will not machine a groove in the face, it does seem bad.   I am in
> Canada, so ice is a reality also.  I think I will keep it simple and stick
> with the gasket--that is acceptable and common.  I will try to resend the
> picture and you guys can see what I am talking about.
> Brian, I think I read that it is bad to put a groove in the seat, also it
> would be pretty tricky at this point.  I finally have a real nice seat that
> I am totally happy with.  I got some pointers from karl Stanley that have
> worked well.  I was over thinking it as usual. lol
> Hank
>
>
> On Wednesday, July 27, 2016 8:38 PM, Sean T. Stevenson via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
>
> I would not machine a groove in the conical face of the port. Instead, use
> the chamfer on the outer face, and squeeze a ring between that, the seat,
> and the retaining ring.
> Sean
>
>
> On July 27, 2016 7:24:18 PM MDT, hank pronk via Personal_Submersibles <
> personal_submersibles at psubs.org> wrote:
>
> Hi Sean,
> Yes I did email it-- it is actually a picture from the Stichiw book, and
> is considered an acceptable option.  I bet if I read it again I will find
> the spec for the seal.  Personally I like the idea of an o-ring in the
> port.  I always though that was bad, but I would sure prefer that.  Today I
> came across a  section in the Stachiw book showing a test sample port with
> a o-ring groove.  It said there was no cracking initiated from the groove
> because it was close to the high pressure face of the port.   Maybe I
> should chuck her up and machine a grove in it.  What do you think about an
> o-ring.
> Hank
>
>
>
> On Wednesday, July 27, 2016 7:07 PM, Sean T. Stevenson via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
>
> Did you email it? I don't see it.
> I'd be inclined to stick with the PVHO recommendations (or Stachiw's book)
> for sealing arrangements. I think there is some discussion of gasket
> hardness and thickness if using a bearing gasket. I don't recall offhand
> though. A conical frustum window will probably use an o-ring though.
> Sean
>
>
> On July 27, 2016 6:27:11 PM MDT, hank pronk via Personal_Submersibles <
> personal_submersibles at psubs.org> wrote:
>
> Hi Sean,
> Did my picture make it?
> Hank
>
>
> On Wednesday, July 27, 2016 3:41 PM, Sean T. Stevenson via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
>
> Hank - sorry, but a picture is worth a thousand words. Can you post a
> sketch of your present arrangement?
> Sean
>
>
> On July 27, 2016 3:10:03 PM MDT, hank pronk via Personal_Submersibles <
> personal_submersibles at psubs.org> wrote:
>
> Hi Sean,
> I am trying decide the simplest way to create my low pressure seal on my
> conical window.  I has a rubber gasket with silicone originally.   I did
> that so when the acrylic compresses the silicone will drag the gasket along
> for the ride.  I don't think it will compress much because it so oversized
> for the depth.  I am wondering now if a thicker softer gasket is better.
> The gasket would be compressed by the retaining ring.  If the acrylic does
> compress, the gasket can expand to maintain the seal in the event that the
> sub reaches the surface before the acrylic has expanded.
> Do you have a recommendation.
> Thank you
> Hank
>
> ------------------------------
>
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
> ------------------------------
>
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
> ------------------------------
>
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20160728/e0a4d315/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: hatch port.jpg
Type: image/jpeg
Size: 37329 bytes
Desc: not available
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20160728/e0a4d315/attachment-0001.jpg>