<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_1_1447285043519_2729"><span id="yui_3_16_0_1_1447285043519_2808">Hank,</span></div><div dir="ltr" id="yui_3_16_0_1_1447285043519_2731"><span id="yui_3_16_0_1_1447285043519_2730">those tanks have a valve at either end. You could use</span></div><div dir="ltr" id="yui_3_16_0_1_1447285043519_2727"><span id="yui_3_16_0_1_1447285043519_2726">them for flotation & as a variable ballast tanks!</span></div><div id="yui_3_16_0_1_1447285043519_2791">You would need a siphon tube extending in & down from one of the valves</div><div dir="ltr" id="yui_3_16_0_1_1447285043519_2792">for a variable ballast set up.</div><div dir="ltr" id="yui_3_16_0_1_1447285043519_2792">Cheers Alan</div> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1447285043519_2665"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1447285043519_2664"> <div dir="ltr" id="yui_3_16_0_1_1447285043519_2725"> <hr size="1" id="yui_3_16_0_1_1447285043519_2734"> <font size="2" face="Arial" id="yui_3_16_0_1_1447285043519_2733"> <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;">Sent:</span></b> Thursday, November 12, 2015 2:33 AM<br> <b><span style="font-weight: bold;">Subject:</span></b> [PSUBS-MAILIST] buoyancy<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_1_1447285043519_2663"><br><div id="yiv5859658007"><div id="yui_3_16_0_1_1447285043519_2662"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;" id="yui_3_16_0_1_1447285043519_2661"><div id="yiv5859658007yui_3_16_0_1_1447248265971_2399" dir="ltr">I was thinking about using CNG (compressed natural gas) tanks for buoyancy. The type 4 tanks are carbon fibre and rated for 3,600 psi and very light. My idea was to keep the tanks full of compressed air so they can withstand the sub depth rating plus a safety margin. I am liking trawl floats may be better now because they are rated high enough and not air filled. The CNG tanks are much cheaper and conveniently shaped. Hmmm not sure now.??</div><div id="yiv5859658007yui_3_16_0_1_1447248265971_2399" dir="ltr">Any thoughts or concerns anyone????</div><div id="yiv5859658007yui_3_16_0_1_1447248265971_2399" dir="ltr">Hank</div></div></div></div><br>_______________________________________________<br>Personal_Submersibles mailing list<br><a ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org" id="yui_3_16_0_1_1447285043519_2838">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank" id="yui_3_16_0_1_1447285043519_2680">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br><br><br></div> </div> </div> </div></body></html>