<html><head></head><body><p dir="ltr">Hank, your best bet is to arrange your MBTs such that they flood completely every time with no residual bubble(s), at which point you should have very slight positive buoyancy when correctly ballasted. Add a small VBT, either internally or externally in a hard tank (you could blow this with HP air instead of pumping, but would need to valve it to isolate it from ambient pressure changes), to compensate for minor crew weight differences, and compensate for the major ones by adding or removing lead.</p>
<p dir="ltr">You want to avoid a situation where a depth change creates a buoyancy change, except in the sole case where you have blown your tanks to ascend.</p>
<p dir="ltr">Sean<br>
</p>
<br><br><div class="gmail_quote">On August 27, 2015 7:13:27 AM MDT, hank pronk via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<table cellspacing="0" cellpadding="0" border="0"><tbody><tr><td valign="top"><div>Alan,<br />It won't work unless there is a check valve between the second stage regulator and the ballast tank. Okay to complicated, bad idea.<br />Hank <br /> <br clear="none" /><br /> <div><br /> <div style="font-size:0.9em;"><br /> <hr size="1" /><br /> <b><br /> <span style="font-weight:bold;">From:</span><br /> </b><br /> hank pronk via Personal_Submersibles <personal_submersibles psubs.org="psubs.org">; <br clear="none" /><br /> <b><br /> <span style="font-weight:bold;">To:</span><br /> </b><br /> Personal Submersibles General Discussion <personal_submersibles psubs.org="psubs.org">; <br clear="none" /><br /> <b><br /> <span style="font-weight:bold;">Subject:</span><br /> </b><br /> Re: [PSUBS-MAILIST] new video <br clear="none" /><br /> <b><br /> <span style="font-weight:bold;">Sent:</span><br /> </b><br /> Thu, Aug 27, 2015 11:36:09 AM <br clear="none" /><br />
</personal_submersibles></personal_submersibles></div><br /> <br clear="none" /><br /> <table cellspacing="0" cellpadding="0" border="0"><tbody><tr><td colspan="1" rowspan="1" valign="top"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"><div><span>Alan,</span></div><div dir="ltr" id="yui_3_16_0_1_1440673788233_2986"><span>I am not sure if my </span>idea will work . When I sink Gamma, there is an air bubble remaining in the ballast tank, the size is determined by the weight of the sub. If I have a first and second stage regulator feeding air to the ballast tank, the regulator will feed air into the ballast tank as I sink keeping the bubble the same size while I sink. Right now it is completely manual and takes practise but it works. I can use both systems ( manual or regulated) by simply turning the air supply on or off to the external regulators. With the regulator
system, I would not have to worry about keeping the sub at an ideal
weight. </div><div dir="ltr" id="yui_3_16_0_1_1440673788233_2986">Hank</div> <br clear="none" /><div class="qtdSeparateBR"><br clear="none" /><br clear="none" /></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 class="yqt1649066208" id="yqt52696"><div dir="ltr"> <font size="2" face="Arial"> On Thursday, August 27, 2015 12:03 AM, Alan via Personal_Submersibles <personal_submersibles psubs.org="psubs.org"> wrote:<br clear="none" /> </personal_submersibles></font> </div> <br clear="none" /><br clear="none" /> <div class="y_msg_container"><div id="yiv1047596452"><div><div>Thanks Hank,</div><div>must be this one, the umbrella dive.</div><div><a rel="nofollow" shape="rect" target="_blank"
href="https://m.youtube.com/watch?v=sflIEnkTth4">https://m.youtube.com/watch?v=sflIEnkTth4</a></div><div>Sent a reply to your post about using a second stage attached to your</div><div>ballast tank, but it didn't come back to me.</div><div>not sure how it would work!</div><div>Alan<br clear="none" /><br clear="none" />Sent from my iPad</div><div class="yiv1047596452yqt7882620191" id="yiv1047596452yqt69389"><div><br clear="none" />On 27/08/2015, at 1:30 pm, hank pronk via Personal_Submersibles <<a rel="nofollow" shape="rect">personal_submersibles@psubs.org</a>> wrote:<br clear="none" /><br clear="none" /></div><blockquote type="cite"><div><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="yiv1047596452yui_3_16_0_1_1440638982967_2475">made some dive<br /> video's today, posted one on youtube under Hank
Pronk</div></div></div></blockquote></div><blockquote type="cite"><div><span>_______________________________________________</span><br clear="none" /><span>Personal_Submersibles mailing list</span><br clear="none" /><span><a rel="nofollow" shape="rect">Personal_Submersibles@psubs.org</a></span><br clear="none" /><span><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></span><br clear="none" /></div></blockquote></div></div><br clear="none" /><div class="yqt7882620191" id="yqt10294">_______________________________________________<br clear="none" />Personal_Submersibles mailing list<br clear="none" /><a rel="nofollow" shape="rect">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></td></tr></tbody></table><br /> </div><br /> </div><br /> <br /></td></tr></tbody></table> <div id="_origMsg_">
<div>
<br />
<div>
<div style="font-size:0.9em">
<hr size="1" />
<b>
<span style="font-weight:bold">From:</span>
</b>
hank pronk via Personal_Submersibles <personal_submersibles@psubs.org>; <br />
<b>
<span style="font-weight:bold">To:</span>
</b>
Personal Submersibles General Discussion <personal_submersibles@psubs.org>; <br />
<b>
<span style="font-weight:bold">Subject:</span>
</b>
Re: [PSUBS-MAILIST] new video <br />
<b>
<span style="font-weight:bold">Sent:</span>
</b>
Thu, Aug 27, 2015 11:36:09 AM <br />
</div>
<br />
<table cellspacing="0" cellpadding="0" border="0"><tbody><tr><td valign="top"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;"><div><span>Alan,</span></div><div dir="ltr" id="yui_3_16_0_1_1440673788233_2986"><span>I am not sure if my </span>idea will work . When I sink Gamma, there is an air bubble remaining in the ballast tank, the size is determined by the weight of the sub. If I have a first and second stage regulator feeding air to the ballast tank, the regulator will feed air into the ballast tank as I sink keeping the bubble the same size while I sink. Right now it is completely manual and takes practise but it works. I can use both systems ( manual or regulated) by simply turning the air supply on or off to the external regulators. With the regulator system, I would not have to worry about keeping the sub at an ideal weight.
</div><div dir="ltr" id="yui_3_16_0_1_1440673788233_2986">Hank</div> <br clear="none" /><div class="qtdSeparateBR"><br clear="none" /><br clear="none" /></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 class="yqt2388334806" id="yqt46867"><div dir="ltr"> <font size="2" face="Arial"> On Thursday, August 27, 2015 12:03 AM, Alan via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br clear="none" /> </font> </div> <br clear="none" /><br clear="none" /> <div class="y_msg_container"><div id="yiv1047596452"><div><div>Thanks Hank,</div><div>must be this one, the umbrella dive.</div><div><a rel="nofollow" shape="rect" target="_blank"
href="https://m.youtube.com/watch?v=sflIEnkTth4">https://m.youtube.com/watch?v=sflIEnkTth4</a></div><div>Sent a reply to your post about using a second stage attached to your</div><div>ballast tank, but it didn't come back to me.</div><div>not sure how it would work!</div><div>Alan<br clear="none" /><br clear="none" />Sent from my iPad</div><div class="yiv1047596452yqt7882620191" id="yiv1047596452yqt69389"><div><br clear="none" />On 27/08/2015, at 1:30 pm, hank pronk via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="javascript:return">personal_submersibles@psubs.org</a>> wrote:<br clear="none" /><br clear="none" /></div><blockquote type="cite"><div><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="yiv1047596452yui_3_16_0_1_1440638982967_2475">made some dive
video's today, posted one on youtube under Hank Pronk</div></div></div></blockquote></div><blockquote type="cite"><div><span>_______________________________________________</span><br clear="none" /><span>Personal_Submersibles mailing list</span><br clear="none" /><span><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="javascript:return">Personal_Submersibles@psubs.org</a></span><br clear="none" /><span><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></span><br clear="none" /></div></blockquote></div></div><br clear="none" /><div class="yqt7882620191" id="yqt10294">_______________________________________________<br clear="none" />Personal_Submersibles mailing list<br clear="none" /><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank"
href="javascript:return">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></td></tr></tbody></table>
</div>
</div>
</div>
<p style="margin-top: 2.5em; margin-bottom: 1em; border-bottom: 1px solid #000"></p><pre class="k9mail"><hr /><br />Personal_Submersibles mailing list<br />Personal_Submersibles@psubs.org<br /><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br /></pre></blockquote></div></body></html>