<table cellspacing="0" cellpadding="0" border="0"><tr><td valign="top"><div>Alan,<br />I am such a dope, forgot they were brushless. <br />Hank</div></td></tr></table> <div id="_origMsg_">
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Alan via Personal_Submersibles <personal_submersibles@psubs.org>; <br>
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Personal Submersibles General Discussion <personal_submersibles@psubs.org>; <br>
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Re: [PSUBS-MAILIST] Rotary oil seal question <br>
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Thu, Oct 15, 2015 5:22:08 PM <br>
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<td valign="top"><div>Thanks Hank,</div><div>I am using the Viton seals because they are more heat resistant,</div><div>but don't think I will be doing more than 3000 rpm & the shaft is only 10mm.</div><div>Am using brushless motors, so no problem with brush contact :)</div><div>That's a good thought re putting in a sleeve to go from the larger to smaller seal,</div><div>hadn't thought of that. I will try just press fitting from the front.</div><div>Alan</div><div><br clear="none"><br clear="none">Sent from my iPad</div><div class="yqt4312318880" id="yqt90695"><div><br clear="none">On 16/10/2015, at 1:40 am, 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 id="yui_3_16_0_1_1444911849716_2658"><span>Hi Alan,</span></div><div dir="ltr" id="yui_3_16_0_1_1444911849716_2658"><span id="yui_3_16_0_1_1444911849716_2692">I have used both seals that you mention, I never retained the seals, they are a press fit. If you go with the low pressure seal first and want to change to the higher pressure seal later, you can just make a bushing to adapt your housing (I had to do that) . Your enemy is RPM, if I recall your motors run real fast. For that reason, I would try the low pressure seal first and I would air compensate them, that low pressure seal is perfectly happy at 3,600 RPM. I have a feeling that high RPM will create a lot of drag in oil and your brushes will struggle to make contact. I like oil compensating for the ease of it all, but think air compensating
is better. </span></div><div dir="ltr" id="yui_3_16_0_1_1444911849716_2658">Hank</div><div dir="ltr" id="yui_3_16_0_1_1444911849716_2658">magnetic couplers is best though</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 dir="ltr"> <font size="2" face="Arial"> On Wednesday, October 14, 2015 9:11 PM, Alan James 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"> </font> </div> <br clear="none"><br clear="none"> <div class="y_msg_container"><div
id="yiv5770773980"><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479">Hi,</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">am working away on my brushless thruster.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">I am looking at 2 different options for rotary oil lip seals on a 10mm shaft.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">Both are viton one is rated for 6-7psi the other is 145psi.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">They have different O.D.s so I need to machine for one or the other.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">I am either oil or air compensating, so the seal will be seeing less than the rated pressure </div><div dir="ltr"
id="yiv5770773980yui_3_16_0_1_1444876194884_2479">on the low pressure seal.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">My thoughts are that the H/P seal may give me a bit more longevity if it wears, & a</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">comfort margin. However I am not sure whether the extra pressure on the shaft would be </div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">a problem or how much the H/P seal would impede the turning of the shaft.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">Also I haven't resolved how I am going to fit it. Options are to press fit it externally from the propeller</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">end with or without a circlip to retain it. Or alternatively a bolt on plate to retain it.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">If I don't go
with any form of retaining & rely on the press fit, am I best to glue it in?</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">The other alternative is to fit it from inside the housing against a shoulder, with an internal</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">circlip retaining it.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">Any thoughts & opinions on this thanks.</div><div dir="ltr" id="yiv5770773980yui_3_16_0_1_1444876194884_2479">Alan</div></div></div></div><br clear="none">_______________________________________________<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"><br clear="none"><br clear="none"></div> </div> </div> </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></td>
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