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<div dir="ltr" data-setdir="false">Brian, what is the max depth you are trying to achieve?</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">At 300 feet, if the reservoir is full, a 5 foot hose will only give you about .652 inch air gap. Not much of a buffer between oil and water. I ran some volume numbers based upon 3x24 reservoir and there will be plenty of air gap the first dive but it sounds like Alan has a good point regarding multiple dives. Have you thought about using a smaller diameter hose and coiling it so you increase the air gap size but in a compact manner?</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">I'm curious about something else. If oil gets from the motor into the reservoir you end up with a mix of oil and water, which makes it a "sacrificial" system rather than one in which you can transfer the oil back to the motor after dive ops. Would a check valve be appropriate on the oil hose to combat this?</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Jon</div><div dir="ltr" data-setdir="false"><br></div><div><br></div>
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On Friday, March 27, 2020, 06:28:04 PM EDT, Alan via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="ydpc23843yiv3094288803"><div><div></div><div>Brian,</div><div>yes, but depending on your depth & ascents, descents within your dive</div><div>profile, the reservoir will fill with water defeating it's purpose. If you do</div><div>a second dive there is no way of clearing it of water so you may as well</div><div>just have a hose.</div><div>In my pool experiments with my home made thruster, I was observing the </div><div>compensating oil moving up the oil hose by a few inches every time I</div><div>turned on the motor & I have a minuscule volume of oil. In other words the</div><div>motor is acting like a pump & throwing the oil out. So one reason to</div><div>have some over pressure is to keep the oil in the housing. It is critical for me </div><div>as I have a high powered small motor that relies on the oil for cooling.</div><div>Maybe you could take the hose off the reservoir on the motor side, fill the </div><div>hose to a couple of inches from the top & turn the motor on to check this,</div><div>as if this is happening then that will be something else you need to factor in.</div><div>Got a nation wide shut down at the moment but allowed to walk to the beach</div><div>not sure that I can even go fishing there. No boats allowed out. :(</div><div>Alan</div><div><br clear="none"></div><div class="ydpc23843yiv3094288803yqt9436757876" id="ydpc23843yiv3094288803yqt11597"><div><br clear="none">On 28/03/2020, at 10:12 AM, Brian Cox via Personal_Submersibles <<a shape="rect" href="mailto:personal_submersibles@psubs.org" rel="nofollow" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br clear="none"><br clear="none"></div><blockquote type="cite"><div><div style="font-family:Arial, sans-serif;font-size:10pt;"><font size="2">Alan, </font><div><font size="2"> Assume the oil goes all the way up to the high point of the oil tube, and then assume the water goes all the way up the water side tube and fills the reservoir all the way up to the top. Then the only air remaining in the system is at the very top of the reservoir . That would be the condition at maximum depth. No? </font></div><div><font size="2"><br clear="none"></font></div><div><font size="2">Brian</font></div><div><font size="2"><br clear="none"></font></div><div><font size="2"><br clear="none"></font><br clear="none"><span style="font-size:10pt;">--- <a shape="rect" href="mailto:personal_submersibles@psubs.org" rel="nofollow" target="_blank">personal_submersibles@psubs.org</a> wrote:</span><br clear="none"><br clear="none"><span style="font-size:10pt;">From: Alan via Personal_Submersibles <<a shape="rect" href="mailto:personal_submersibles@psubs.org" rel="nofollow" target="_blank">personal_submersibles@psubs.org</a>></span><br clear="none"><span style="font-size:10pt;">To: Personal Submersibles General Discussion <<a shape="rect" href="mailto:personal_submersibles@psubs.org" rel="nofollow" target="_blank">personal_submersibles@psubs.org</a>></span><br clear="none"><span style="font-size:10pt;">Subject: Re: [PSUBS-MAILIST] right side up compensator</span><br clear="none"><span style="font-size:10pt;">Date: Sat, 28 Mar 2020 09:59:43 +1300</span><br clear="none"><br clear="none"><div style="font-size:10pt;"></div><div style="font-size:10pt;">Brian,</div><div style="font-size:10pt;">that would work to 30ft at the most. </div><div style="font-size:10pt;">If the volume in the reservoir was 1 litre & the volume in the hose going</div><div style="font-size:10pt;">down in to the water was half a litre, then at 30ft the volume would be compressed </div><div style="font-size:10pt;">to half. So the reservoir needs another half a litre to achieve this. And that </div><div style="font-size:10pt;">would mean that the half a litre in the hose would move in to the reservoir &</div><div style="font-size:10pt;">the hose would fill up with water.</div><div style="font-size:10pt;">The main problem is you haven't worked out how much the oil might expand.</div><div style="font-size:10pt;">If you did that you would have a ball park figure to work on.</div><div style="font-size:10pt;">You may find that a hose without a reservoir would suffice.</div><div style="font-size:10pt;">Or hose with small bladder on the end.</div><div style="font-size:10pt;">Cheers Alan</div><div style="font-size:10pt;"><br clear="none"></div><div style="font-size:10pt;"><br clear="none">On 28/03/2020, at 8:20 AM, Brian Cox via Personal_Submersibles <<a shape="rect" href="mailto:personal_submersibles@psubs.org" rel="nofollow" target="_blank">personal_submersibles@psubs.org</a>> wrote:<br clear="none"><br clear="none"></div><blockquote style="font-size:10pt;"><div><div style="font-family:Arial, sans-serif;font-size:10pt;"><font size="2">Here it is right side up hopefully </font></div></div></blockquote><blockquote style="font-size:10pt;"><div><IMGr_1522.jpg></div></blockquote><blockquote style="font-size:10pt;"><div><span>_______________________________________________</span><br clear="none"><span>Personal_Submersibles mailing list</span><br clear="none"><span><a shape="rect" href="mailto:Personal_Submersibles@psubs.org" rel="nofollow" target="_blank">Personal_Submersibles@psubs.org</a></span><br clear="none"><span><a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" rel="nofollow" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a></span><br clear="none"></div></blockquote><span style="font-size:10pt;">_______________________________________________
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