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<div dir="ltr" data-setdir="false" style="">John, I think mineral oil might work. See page III-11, section 3.5 in <span style="font-family: Arial, sans-serif; font-size: 10pt; line-height: 14.2667px; outline: none !important;"><span style="outline: none !important;"><span style="font-stretch: normal; font-size: 7pt; line-height: normal; font-family: Times New Roman; outline: none !important;"> </span></span></span><span style="font-family: Arial, sans-serif; font-size: 10pt; line-height: 14.2667px; outline: none !important;">"</span><span style="line-height: 14.2667px; outline: none !important;"><font color="#333333" face="Arial, sans-serif" style="background-color: inherit;"><div style="font-family: times new roman, new york, times, serif; font-size: 16px;"><div><br></div><div><div style="font-family: Helvetica Neue, Helvetica, Arial, sans-serif;"><a href="https://apps.dtic.mil/sti/citations/AD0894795" style="color: rgb(25, 106, 212); text-decoration-line: underline;" rel="nofollow" target="_blank">https://apps.dtic.mil/sti/citations/AD0894795</a></div><div style="font-family: Helvetica Neue, Helvetica, Arial, sans-serif;"><br></div></div></div><font face="times new roman, new york, times, serif"><span style="font-size: 10pt;"> I don't know anything about </span></font><span style="font-size: 13.3333px;">these thruster</span><font face="times new roman, new york, times, serif"><span style="font-size: 10pt;"> motors but this </span></font><span style="font-family: times new roman, new york, times, serif; font-size: 13.3333px;">oil</span><span style="font-family: times new roman, new york, times, serif; font-size: 10pt;"> is a </span><span style="font-family: times new roman, new york, times, serif; font-size: 13.3333px;">petroleum</span><span style="font-family: times new roman, new york, times, serif; font-size: 10pt;"> base, red, </span><span style="font-family: times new roman, new york, times, serif; font-size: 13.3333px;">hydraulic</span><span style="font-family: times new roman, new york, times, serif; font-size: 10pt;"> oil that is essentially </span><span style="font-family: times new roman, new york, times, serif; font-size: 13.3333px;">mineral</span><span style="font-family: times new roman, new york, times, serif; font-size: 10pt;"> oil. See </span></font></span><a href="https://petroleumservicecompany.com/blog/what-is-mil-h-5606/" style="font-family: times new roman, new york, times, serif; font-size: 16px;" rel="nofollow" target="_blank">https://petroleumservicecompany.com/blog/what-is-mil-h-5606/</a> for more info on <font color="#333333" face="Arial, sans-serif" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><span style="font-size: 13.3333px;">MIL-H-5606. It has a kinematic viscosity of 13.8 cs at 100 F and 0 psig. More than likely this is brushless motor with the brush arcing issues that we are seeing not relevant.</span></font></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 13.3333px;"><br></span></span></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 13.3333px;">Cliff</span></span></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 13.3333px;"><br></span></span></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><span><span style="color: rgb(51, 51, 51); font-family: Arial, sans-serif; font-size: 13.3333px;"><br></span></span></div><div style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div>
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On Friday, July 28, 2023 at 10:02:26 PM CDT, John Bussard via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div id="ydp488cf613yiv1675027751"><div>While a little out of my depth on technical specs here-<div><br clear="none"></div><div>A good friend and coworker here in San Diego has been an interesting person to discuss my “new hobby” with: He briefly worked as an electronic technician on ROVs with the Navy Deep Submergence Unit here, around the turn of this century.</div><div><br clear="none"></div><div>When I told him about this discussion, his memory was that their oil compensation was done with plain old mineral oil.</div><div><br clear="none"></div><div>Unsure if it’s worth considering but thought I’d share that historical context.</div><div><br clear="none"></div><div>John<br clear="none"><br clear="none"><div dir="ltr">Sent from my iPhone</div><div dir="ltr"><div id="ydp488cf613yiv1675027751yqtfd66377" class="ydp488cf613yiv1675027751yqt6704923759"><br clear="none"><blockquote type="cite">On Jul 28, 2023, at 19:46, Alan James via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br clear="none"><br clear="none"></blockquote></div></div><div id="ydp488cf613yiv1675027751yqtfd46717" class="ydp488cf613yiv1675027751yqt6704923759"><blockquote type="cite"><div dir="ltr">Cliff,<div>I don't think brushed motors are the way to go.</div><div>The brushes can contaminate the oil & lift due to the centrifugal force of the oil. And they are less efficient than brushless motors. Also the 101s have that double o-ring seal system, that means one of the o-rings will fail when over 30ft or so.</div><div>A descent brushless option with a ceramic mechanical seal and silicone compensation would be a big improvement.</div><div>I bought some of the Shell Morlina some years ago. An industrial chemist advised me it was low in aromatics and less likely to dissolve plastics than other options. I believe it was used to lubricate high speed spindles etc.</div><div>It still had an effect on plastics.</div><div>Alan </div><div><br clear="none"><div id="ydp488cf613yiv1675027751ymail_android_signature"><a shape="rect" id="ydp488cf613yiv1675027751ymail_android_signature_link" href="https://mail.onelink.me/107872968?pid=nativeplacement&c=Global_Acquisition_YMktg_315_Internal_EmailSignature&af_sub1=Acquisition&af_sub2=Global_YMktg&af_sub3=&af_sub4=100000604&af_sub5=EmailSignature__Static_" rel="nofollow" target="_blank">Sent from Yahoo Mail on Android</a></div> <br clear="none"> <blockquote style="margin:0 0 20px 0;"> <div style="font-family:Roboto, sans-serif;color:#6D00F6;"> <div>On Sat, 29 Jul 2023 at 12:42 pm, Cliff Redus via Personal_Submersibles</div><div><personal_submersibles@psubs.org> wrote:</div> </div> <div style="padding:10px 0 0 20px;margin:10px 0 0 0;border-left:1px solid #6D00F6;"> _______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" href="mailto:Personal_Submersibles@psubs.org" rel="nofollow" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><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><br clear="none"> </div> </blockquote></div><span>_______________________________________________</span><br clear="none"><span>Personal_Submersibles mailing list</span><br clear="none"><span>Personal_Submersibles@psubs.org</span><br clear="none"><span>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</span><br clear="none"></div></blockquote></div></div></div></div><div class="ydp488cf613yqt6704923759" id="ydp488cf613yqtfd05944">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" href="mailto:Personal_Submersibles@psubs.org" rel="nofollow" target="_blank">Personal_Submersibles@psubs.org</a><br clear="none"><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><br clear="none"></div></div>
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