<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px"><div dir="ltr" id="yui_3_16_0_1_1455480291314_2962"><span>The 15 </span>degrees is off vertical. So imagine a vertical line from top to bottom of the centre of the sphere. Then the angle is 15 degrees off that vertical line. The angle could be a pinch more maybe 17 degrees or so. I had a hard time reaching it to measure with the ballast tank in my way.</div><div dir="ltr" id="yui_3_16_0_1_1455480291314_2962">Hank</div> <div class="qtdSeparateBR"><br><br></div><div class="yahoo_quoted" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12px;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div dir="ltr"><font size="2" face="Arial"> On Sunday, February 14, 2016 12:45 PM, Hugh Fulton via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br></font></div> <br><br> <div class="y_msg_container">I thought the idea with conical hatches on spheres was to have the angle of<br clear="none">intersection perpendicular to the surface. i.e. the cone apex being the<br clear="none">centre of the sphere. Hank, Is the 15 degree angle 30 degrees inclusive, 15<br clear="none">degrees inclusive or 15 degrees from the line from sphere centre to hatch<br clear="none">joint?? Hugh <br clear="none"><br clear="none"><br clear="none">-----Original Message-----<br clear="none">From: Personal_Submersibles [mailto:<a shape="rect" ymailto="mailto:personal_submersibles-bounces@psubs.org" href="mailto:personal_submersibles-bounces@psubs.org">personal_submersibles-bounces@psubs.org</a>]<br clear="none">On Behalf Of Sean T. Stevenson via Personal_Submersibles<br clear="none">Sent: Sunday, 14 February 2016 2:45 p.m.<br clear="none">To: Personal Submersibles General Discussion<br clear="none">Subject: Re: [PSUBS-MAILIST] Fw: Elementary 3000 new paint<br clear="none"><br clear="none">At what angle is the interface? I ask because as the shell compresses, that<br clear="none">shell stress will act through the interface on the hatch, and at some<br clear="none">critical angle, will actually act to push the hatch out of the hole<br clear="none">- at least to the extent that the hull shell deflects / gets smaller under<br clear="none">pressure. This is dependent on both the interface angle, the friction<br clear="none">between the two mating surfaces, and the strength of your hatch dogs.<br clear="none">Ideally, you want the hatch to lock in place under the stress and provide<br clear="none">that continuous load path through the hatch dome, instead of being pushed<br clear="none">outboard by the deflecting shell. In the latter case, the deflection will<br clear="none">be minor and probably not represent a sealing problem, but it will cause the<br clear="none">shell to behave as if it doesn't have that continuous load path through the<br clear="none">hatch carrying the full shell stress, necessitating greater reinforcement<br clear="none">around the hole. That said, your hatch land may already be sufficient<br clear="none">reinforcement - that's why I was hoping for a closer look.<br clear="none"><br clear="none">Sean<br clear="none"><br clear="none">On 2016-02-13 15:17, hank pronk via Personal_Submersibles wrote:<br clear="none">> Sean,<br clear="none">> Yes the hatch and seat are conical. The hatch dome is in line with <br clear="none">> the hull so the load path is a smooth line.<br clear="none">> Hank<br clear="none"><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><div class="yqt3697724031" id="yqtfd24750"><br clear="none"><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br><br></div> </div> </div> </div></div></body></html>