<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><span>Hi Sean,</span></div><div><span>We have it all sorted out, and they are going forward, my minimum thickness should be .875 not bad! </span></div><div id="yui_3_16_0_1_1446847125385_3820"><span><br></span></div><div id="yui_3_16_0_1_1446847125385_3777"><span id="yui_3_16_0_1_1446847125385_3776">As for your project, are you releasing clues? Hmmm that means two subs only 5 hr apart, nice! </span></div><div id="yui_3_16_0_1_1446847125385_3777"><span>Hank</span></div> <br><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 Friday, November 6, 2015 2:51 PM, Sean T. Stevenson via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br> </font> </div> <br><br> <div class="y_msg_container"><div id="yiv6408208357"><div><div dir="ltr">Head specifications are always to the inside dimension, as that conforms to the die, and in the case of elliptical (by design) heads, is the only surface that is true 2:1 shape, and thus must be the reference.</div>
<div dir="ltr">Thus, when supplying a drawing or specification, you dimension the inside radii, and then specify the required wall thickness (with tolerance). As the manufacturer, knowing how a part thins during forming, they would then select a plate of sufficient thickness to meet your specification (minimum thickness at apex), resulting in a head which is thicker at the flange. If you drew or specified a maximum thickness tolerance, they would then have to turn it down to meet it (expensive), or you could just accept the extra weight imposed by the thicker flange.</div>
<div dir="ltr">As for roundness, whether you measure inside or out is of little consequence. The thinning should not be so profound as to affect the deviation of the neutral axis within the shell wall carrying the hoop stress, but of course it will be at its worst on the outside, so that is the most conservative option, and is also the easiest to measure. They'd have to really mess up to be grossly out on roundness, however apex thinning is always a possible problem, so specifying that minimum thickness is always a good idea.</div>
<div dir="ltr">As for me, I figured I should finally step away from the drawing board and get something built, so I will be embarking on a project soon. Stay tuned.</div>
<div dir="ltr">Sean</div>
<br clear="none"><br clear="none"><div class="yiv6408208357yqt7572708661" id="yiv6408208357yqtfd95602"><div class="yiv6408208357gmail_quote">On November 6, 2015 1:51:37 PM MST, hank pronk via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<blockquote class="yiv6408208357gmail_quote" style="margin:0pt 0pt 0pt 0.8ex;border-left:1px solid rgb(204, 204, 204);padding-left:1ex;">
<div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"><div><span>Sean,</span></div><div dir="ltr"><span>There is a problem with EE after I paid and was sent the work order I noticed they measure the head height from the inside when in fact the apex is the thinnest. That makes the sphere </span>elliptical. I contacted them and it turns out the template tolerance they said they could meet is measure on the inside. So I am modifying the order so that the heads are measured from the outside, this way they are 1\2 as tall as wide. I will true them up from there.</div><div dir="ltr"><br clear="none"></div><div dir="ltr">Why are you contacting them? are you starting a project? Do tell</div><div dir="ltr" id="yiv6408208357yui_3_16_0_1_1446842811255_2976">Hank</div> <br clear="none"><div class="yiv6408208357qtdSeparateBR"><br clear="none"><br clear="none"></div><div class="yiv6408208357yahoo_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 Friday, November 6, 2015 11:49 AM, Sean T. Stevenson via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br clear="none"> </font> </div> <br clear="none"><br clear="none"> <div class="yiv6408208357y_msg_container"><div id="yiv6408208357"><div><div dir="ltr">Glad that you're making headway. I might be contacting EE myself in short order.</div>
<div dir="ltr">Sean<br clear="none">
</div>
<br clear="none"><br clear="none"><div class="yiv6408208357gmail_quote">On November 2, 2015 5:16:03 PM MST, hank pronk via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<blockquote class="yiv6408208357gmail_quote" style="margin:0pt 0pt 0pt 0.8ex;border-left:1px solid rgb(204, 204, 204);padding-left:1ex;">
<div class="yiv6408208357yqt2393955912" id="yiv6408208357yqt37809"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"><div id="yiv6408208357yui_3_16_0_1_1446508862749_5210">Sean,</div><div dir="ltr" id="yiv6408208357yui_3_16_0_1_1446508862749_5210">I did just as you recommended, I have been talking with EE and they say now they can produce the heads within my tolerance. I told them 1\2 of one percent of dia measured with a 120 degree template. They say they will measure the heads with a template before they ship them. They have been extremely friendly and accommodating . I even told them what it was for.</div><div dir="ltr" id="yiv6408208357yui_3_16_0_1_1446508862749_5210">Thanks' for your input</div><div dir="ltr" id="yiv6408208357yui_3_16_0_1_1446508862749_5210">Hank</div></div></div><div style="margin-top:2.5em;margin-bottom:1em;border-bottom:1px solid #000;"></div><pre class="yiv6408208357k9mail"></pre><hr><br clear="none">Personal_Submersibles mailing list<br clear="none">Personal_Submersibles@psubs.org<br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></blockquote></div></div></div><br clear="none"><div class="yiv6408208357yqt2393955912" id="yiv6408208357yqt91044">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br clear="none"><br clear="none"></div> </div> </div> </div></div><div style="margin-top:2.5em;margin-bottom:1em;border-bottom:1px solid #000;"></div><pre class="yiv6408208357k9mail"></pre><hr><br clear="none">Personal_Submersibles mailing list<br clear="none">Personal_Submersibles@psubs.org<br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></blockquote></div></div></div></div><br><div class="yqt7572708661" id="yqtfd64846">_______________________________________________<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>