<html><head></head><body><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 id="yui_3_16_0_1_1444911849716_2658" dir="ltr"><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 id="yui_3_16_0_1_1444911849716_2658" dir="ltr">Hank</div><div id="yui_3_16_0_1_1444911849716_2658" dir="ltr">magnetic couplers is best though</div> <br><div class="qtdSeparateBR"><br><br></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 <personal_submersibles@psubs.org> wrote:<br> </font> </div> <br><br> <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 id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">am working away on my brushless thruster.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">I am looking at 2 different options for rotary oil lip seals on a 10mm shaft.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">Both are viton one is rated for 6-7psi the other is 145psi.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">They have different O.D.s so I need to machine for one or the other.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">I am either oil or air compensating, so the seal will be seeing less than the rated pressure </div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">on the low pressure seal.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">My thoughts are that the H/P seal may give me a bit more longevity if it wears, & a</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">comfort margin. However I am not sure whether the extra pressure on the shaft would be </div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">a problem or how much the H/P seal would impede the turning of the shaft.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">Also I haven't resolved how I am going to fit it. Options are to press fit it externally from the propeller</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">end with or without a circlip to retain it. Or alternatively a bolt on plate to retain it.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">If I don't go with any form of retaining & rely on the press fit, am I best to glue it in?</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">The other alternative is to fit it from inside the housing against a shoulder, with an internal</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">circlip retaining it.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">Any thoughts & opinions on this thanks.</div><div id="yiv5770773980yui_3_16_0_1_1444876194884_2479" dir="ltr">Alan</div></div></div></div><br>_______________________________________________<br>Personal_Submersibles mailing list<br><a ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br><br><br></div> </div> </div> </div></div></body></html>