<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_1454234817780_2831"><span>Cliff,</span></div><div id="yui_3_16_0_1_1454234817780_2827" dir="ltr"><span id="yui_3_16_0_1_1454234817780_2826">I thought of a way of using that propeller calculator I posted a link to a bit more</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span id="yui_3_16_0_1_1454234817780_2874">accurately. It asks for a draft measurement, but as the whole of a submarine is</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span id="yui_3_16_0_1_1454234817780_3048">under the water you would have to give the draft as the height of the sub from top to</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span id="yui_3_16_0_1_1454234817780_3126">bottom seeing as it's all under water. This may give an erroneous calculation.</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span id="yui_3_16_0_1_1454234817780_3530">It may be better to split the sub in half horizontally & give the draft as half the height</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span id="yui_3_16_0_1_1454234817780_3531">of the sub. Tell the calculator you have 1 thruster not 2 & treat the top half as a mirror image</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span id="yui_3_16_0_1_1454234817780_3532">(well near enough for this purpose) of the bottom. So the suggested prop size & pitch</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span id="yui_3_16_0_1_1454234817780_3533">will be the same for both thrusters. Hope that makes sense.</span></div><div dir="ltr" id="yui_3_16_0_1_1454234817780_2825"><span>Alan</span></div><br> <div class="qtdSeparateBR" id="yui_3_16_0_1_1454234817780_2770"><br><br></div><div class="yahoo_quoted" id="yui_3_16_0_1_1454234817780_2872" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1454234817780_2871"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1454234817780_2870"> <div dir="ltr" id="yui_3_16_0_1_1454234817780_2869"> <font size="2" face="Arial" id="yui_3_16_0_1_1454234817780_2868"> <hr size="1" id="yui_3_16_0_1_1454234817780_2867"> <b><span style="font-weight:bold;">From:</span></b> Alan James 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 id="yui_3_16_0_1_1454234817780_3596"><span style="font-weight: bold;" id="yui_3_16_0_1_1454234817780_3595">Sent:</span></b> Sunday, January 31, 2016 11:54 AM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [PSUBS-MAILIST] Brushless thruster test<br> </font> </div> <div class="y_msg_container"><br><div id="yiv0287279501"><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"><div id="yiv0287279501yui_3_16_0_1_1454191391989_2866"><span>Cliff,</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><span id="yiv0287279501yui_3_16_0_1_1454191391989_2810">the prop is a 3 blade 7&1/4" x 4" pitch off a yamaha 2hp motor.</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3490">The motor diameter is 63mm diameter x 74mm long (called a 6374) about 2&1/2'' x 3"</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><span>About 3hp specs below.</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><a rel="nofollow" shape="rect" id="yiv0287279501yui_3_16_0_1_1454191391989_3884" target="_blank" href="http://www.hobbyking.com/hobbyking/store/__18184__Turnigy_Aerodrive_SK3_6374_149kv_Brushless_Outrunner_Motor.html">Turnigy Aerodrive SK3 - 6374-149kv Brushless Outrunner Motor</a><br clear="none"></div><div class="yiv0287279501link-enhancr-attachment yiv0287279501link-enhancr-element yiv0287279501richcompose-card" id="yiv0287279501enhancrCard_0" style="width:450px;font-family:'Georgia', 'Times', 'Times New Roman', 'serif';margin-top:5px;margin-bottom:5px;background-color:#ffffff;"><table class="yiv0287279501link-enhancr-element" id="yiv0287279501yui_3_16_0_1_1454191391989_4297" cellspacing="0" cellpadding="0" border="0" 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style="margin:0;font-weight:normal;margin-bottom:3px;font-size:18px;line-height:21px;max-height:43px;color:#000000;overflow:hidden;display:inline-block;">Turnigy Aerodrive SK3 - 6374-149kv Brushless Outrunner...</span></a><div class="yiv0287279501link-enhancr-card-description yiv0287279501link-enhancr-element" id="yiv0287279501yui_3_16_0_1_1454191391989_4842" style="font-size:13px;line-height:20px;color:#999999;max-height:81px;font-family:'Georgia', 'Times', 'Times New Roman', 'serif';overflow:hidden;">Turnigy Aerodrive SK3 - 6374-149kv Brushless Outrunner Motor</div></div></div></td></tr><tr><td colspan="2" rowspan="1" class="yiv0287279501link-enhancr-element" style="height:4px;background-color:#ffffff;font-size:0pt;border-collapse:collapse;"><div class="yiv0287279501link-enhancr-element" style="height:4px;background-color:#ffffff;font-size:4pt;"></div></td></tr><tr id="yiv0287279501yui_3_16_0_1_1454191391989_4303"><td colspan="1" rowspan="1" class="yiv0287279501link-enhancr-element" 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style="vertical-align:middle;font-size:9px;line-height:11px;color:#999999;">Preview by Yahoo</span></div></td></tr><tr id="yiv0287279501yui_3_16_0_1_1454191391989_4888"><td colspan="2" rowspan="1" class="yiv0287279501link-enhancr-element" id="yiv0287279501yui_3_16_0_1_1454191391989_4887" style="height:9px;background-color:#ffffff;font-size:0pt;border-collapse:collapse;"><div class="yiv0287279501link-enhancr-element" id="yiv0287279501yui_3_16_0_1_1454191391989_4886" style="height:9px;background-color:#ffffff;font-size:9pt;"></div></td></tr><tr class="yiv0287279501link-enhancr-element" id="yiv0287279501yui_3_16_0_1_1454191391989_4850"><td colspan="8" rowspan="1" class="yiv0287279501link-enhancr-element" id="yiv0287279501yui_3_16_0_1_1454191391989_4849" style="height:1px;background-color:#e5e5e5;font-size:1px;border-collapse:collapse;"><div class="yiv0287279501link-enhancr-element" id="yiv0287279501yui_3_16_0_1_1454191391989_4848" style="height:1px;background-color:#e5e5e5;font-size:1px;line-height:0px;"> </div></td></tr></tbody></table></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">To measure the thrust I designed a wooden apparatus that fitted to the steps of my nephews swimming pool.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">It is a beam that extends horizontally out over the swimming pool & has a vertical member going down in to the pool</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">that is hinged at it's half way point. At the bottom of the vertical member the thruster is mounted, & at an equal</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">distance above the hinge is an eye bolt for connecting a cable to some electronic scales. There is another eye bolt</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">near the start of the horizontal beam & the scales are suspended between these two eye bolts.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">In my set up I can only measure forward thrust.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">Before I made the housing I did an initial test with no housing & just bolted the mounting bracket that comes with it </div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">to a similar test rig. It had lots of grunt despite the fact it was submerged as is, in fresh water. </div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">I had a little bit of rust on the magnets afterward & I think some crc would have helped.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"> If you want to get technical on the test, here is a good paper.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><a rel="nofollow" shape="rect" id="yiv0287279501yui_3_16_0_1_1454191391989_4553" target="_blank" href="http://www.tahoebenchmark.com/pdfs/2009/DPVBollardPullv2.pdf">http://www.tahoebenchmark.com/pdfs/2009/DPVBollardPullv2.pdf</a><br clear="none"></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"> Some of my calculations on propeller size & motor hp were based on results from online propeller calculators.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><a rel="nofollow" shape="rect" id="yiv0287279501yui_3_16_0_1_1454191391989_4801" target="_blank" href="https://www.vicprop.com/calculator.htm">https://www.vicprop.com/calculator.htm</a></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">but the inputs referred to boats not subs so not totally accurate.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"> I was looking at variable pitch propellers yesterday & wondered if there would be any benefit considering the</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">small speed range we operate at.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"> I was googling to try & find out the bollard thrust results for the 101, because I am not beleiving what they say.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">I have a theory that the Minn kotas are over sized to deal with the heat that builds up inside the can. I would</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">be interested in your results.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">Am pretty convinced that brushless & oil compensated is the way to go. If you grind metal hard out & it heats up</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">you can cool it instantaneously with water but if you leave it in air it takes a long time to cool. There is always an air</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">gap in a motor between the magnets & rotor, but large gaps at the ends of the coils (front & back of motor) so oil</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">compensating would be a lot easier on the motor. Brushes can have problems lifting in oil, so the brushless</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">oil compensated motor seems the way to go.</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811">Cheers Alan</div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><br clear="none"></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2811"><br clear="none"></div><br clear="none"> <div class="yiv0287279501qtdSeparateBR" id="yiv0287279501yui_3_16_0_1_1454191391989_2871"><br clear="none"><br clear="none"></div><div class="yiv0287279501yahoo_quoted" id="yiv0287279501yui_3_16_0_1_1454191391989_2815" style="display:block;"> <div id="yiv0287279501yui_3_16_0_1_1454191391989_2814" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div id="yiv0287279501yui_3_16_0_1_1454191391989_2813" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div class="yiv0287279501yqt2483980314" id="yiv0287279501yqt60985"><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2812"> <font id="yiv0287279501yui_3_16_0_1_1454191391989_2873" size="2" face="Arial"> </font><hr id="yiv0287279501yui_3_16_0_1_1454191391989_2872" size="1"> <b><span style="font-weight:bold;">From:</span></b> Cliff Redus via Personal_Submersibles <personal_submersibles@psubs.org><br clear="none"> <b><span style="font-weight:bold;">To:</span></b> Personal Submersibles General Discussion <personal_submersibles@psubs.org> <br clear="none"> <b><span style="font-weight:bold;">Sent:</span></b> Sunday, January 31, 2016 10:55 AM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> Re: [PSUBS-MAILIST] Brushless thruster test<br clear="none"> </div> <div class="yiv0287279501y_msg_container" id="yiv0287279501yui_3_16_0_1_1454191391989_2819"><br clear="none"><div id="yiv0287279501"><div id="yiv0287279501yui_3_16_0_1_1454191391989_2818"><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2817"><div id="yiv0287279501yui_3_16_0_1_1454191391989_3209">Alan your thruster is coming along. What is the pitch of the prop that you are going to use? It is a little hard to tell the size of the unit from the pictures. What is the prop diameter and what is motor diameter?</div><div id="yiv0287279501yui_3_16_0_1_1454191391989_3210"><br clear="none"></div><div id="yiv0287279501yui_3_16_0_1_1454191391989_3211">I am working with some engineering students on a new variable pitch prop for my boat. They have also built a test rig to measure the bollard thrust, rpm, current and voltage of the thruster. Hopefully in a week or so we will get some testing done a a MK-33 prop that goes with the MK-101 lower unit.</div><div id="yiv0287279501yui_3_16_0_1_1454191391989_2834"><br clear="none"></div><div id="yiv0287279501yui_3_16_0_1_1454191391989_3212">How did you measure the thrust on your thruster? How did you calibrate the test rig? What kind of duty cycle is this motor rated for? What do think the final HP will be for your thruster?</div><div id="yiv0287279501yui_3_16_0_1_1454191391989_3155"><br clear="none"></div><div id="yiv0287279501yui_3_16_0_1_1454191391989_2833">Thanks for sharing your work to date on the thruster.</div><div id="yiv0287279501yui_3_16_0_1_1454191391989_3154"><br clear="none"></div><div id="yiv0287279501yui_3_16_0_1_1454191391989_2816">Cliff</div></div><div class="yiv0287279501gmail_extra" id="yiv0287279501yui_3_16_0_1_1454191391989_2825"><br clear="none"><div class="yiv0287279501gmail_quote" id="yiv0287279501yui_3_16_0_1_1454191391989_2824">On Sat, Jan 30, 2016 at 12:43 PM, Alan James via Personal_Submersibles <span dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_3813"><<a rel="nofollow" shape="rect" id="yiv0287279501yui_3_16_0_1_1454191391989_3812" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>></span> wrote:<br clear="none"><blockquote class="yiv0287279501gmail_quote" id="yiv0287279501yui_3_16_0_1_1454191391989_2823" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div class="yiv0287279501yqt9617941935" id="yiv0287279501yqt36923"><div id="yiv0287279501yui_3_16_0_1_1454191391989_2822"><div id="yiv0287279501yui_3_16_0_1_1454191391989_2821" style="color:rgb(0,0,0);font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;background-color:rgb(255,255,255);"><div id="yiv0287279501yui_3_16_0_1_1454191391989_2832"><span>Hank, Tim.</span></div><div id="yiv0287279501yui_3_16_0_1_1454191391989_2831"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3153">With a load on it should be about 1300 rpm.</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2830"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3152">It was leaking just sitting in the pool. When I got home</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2829"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3151">I poured a low viscosity oil in the wire entry & it just flowed</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_2820"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3751">out the seal. </span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_3150"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3149">It is quite a learning experience. There are some big gaps in my understanding </span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_3148"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3752">of the maths of what is going on.</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_3123"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3122">I am getting a 1500W sensored motor with low kv & an operational voltage of 44V</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_3754"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3753">made up for me. The motors I have are sensorless & it is hard to find a good</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_3121"><span id="yiv0287279501yui_3_16_0_1_1454191391989_3755">speed controller with reverse for sensorless motors.</span></div><div dir="ltr" id="yiv0287279501yui_3_16_0_1_1454191391989_3801"><span>Alan</span></div><br clear="none"> <div id="yiv0287279501yui_3_16_0_1_1454191391989_3120"><br clear="none"><br clear="none"></div><div style="display:block;"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div dir="ltr"> <font face="Arial" size="2"> </font><hr size="1"> <b><span style="font-weight:bold;">From:</span></b> hank pronk via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none"> <b><span style="font-weight:bold;">To:</span></b> Personal Submersibles General Discussion <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> <br clear="none"> <b><span style="font-weight:bold;">Sent:</span></b> Sunday, January 31, 2016 7:08 AM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> Re: [PSUBS-MAILIST] Brushless thruster test<br clear="none"> </div> <div><br clear="none"><div><div><div style="color:rgb(0,0,0);font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;background-color:rgb(255,255,255);"><div><span>Alan,</span></div><div><span>That motor looks pretty nice! I still think rpm is your enemy, seal wise.</span></div><div><span>Hank</span></div> <div><br clear="none"><br clear="none"></div><div 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><div dir="ltr"><font face="Arial" size="2"> On Saturday, January 30, 2016 9:20 AM, T Novak via Personal_Submersibles <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none"></font></div> <br clear="none"><br clear="none"> <div><div><div><div><div><span style="font-size:11pt;">Thanks for the update, Alan.</span></div><div><span style="font-size:11pt;">It looks like your research is coming along quite well.</span></div><div><span style="font-size:11pt;">Tim</span></div><div><span style="font-size:11pt;"> </span></div><div><div><div style="border-width:1pt medium medium;border-style:solid none none;border-color:rgb(225,225,225) currentColor currentColor;padding:3pt 0in 0in;"><div><b><span lang="EN-US" style="font-size:11pt;">From:</span></b><span lang="EN-US" style="font-size:11pt;"> Personal_Submersibles [mailto:<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles-bounces@psubs.org" target="_blank" href="mailto:personal_submersibles-bounces@psubs.org">personal_submersibles-bounces@psubs.org</a>] <b>On Behalf Of </b>Alan James via Personal_Submersibles<br clear="none"><b>Sent:</b> Saturday, January 30, 2016 1:47 AM<br clear="none"><b>To:</b> Personal Submersibles General Discussion <<a rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org" target="_blank" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>><br clear="none"><b>Subject:</b> [PSUBS-MAILIST] Brushless thruster test</span></div></div></div><div> </div><div><div><div style="background:white;"><span>I had an initial pool test of my brushless thruster yesterday.</span></div></div><div><div style="background:white;"><span>Thruster is on projects page <a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/projects/1235435392/brushlessthruster/">http://www.psubs.org/projects/1235435392/brushlessthruster/</a></span></div></div><div><div style="background:white;"><span>A bit of a mixed bag. Firstly I was testing it on 36-37 V & not 44 that it was designed for,</span></div></div><div><div style="background:white;"><span>due to size restrictions on import of Lithium polymer batteries. I will buy the additional voltage.</span></div></div><div><div style="background:white;"><span> I was getting 5kg (11lb) thrust off 150W & 10kg (22lb) off 515W, which is comparable &</span></div></div><div><div style="background:white;"><span>better than some commercial direct drive BLDC thrusters that I have specs on.</span></div></div><div><div style="background:white;"><span>However I got to 13kg thrust & the propeller seemed to slip at that point & even though </span></div></div><div><div style="background:white;"><span>it was running at 2,200W I wasn't getting any more thrust. I was only a couple of feet out </span></div></div><div><div style="background:white;"><span>from the pool edge when testing, so that could be contributing.</span></div></div><div><div style="background:white;"><span>Another factor could have been that the seal leaked badly & the motor was short circuiting </span></div></div><div><div style="background:white;"><span>through the water. Why did the seal leak? Possibly I damaged it hammering it in to it's housing</span></div></div><div><div style="background:white;"><span>or because I didn't polish up the propeller shaft. </span></div></div><div><div style="background:white;"><span>I have other motors I will be testing, so a lot more work & learning to do on this one.</span></div></div><div><div style="background:white;"><span>I did notice I had the same problem as Cliff, with the motor wiring starting to wear through</span></div></div><div><div style="background:white;"><span>where it comes out of the housing.</span></div></div><div><div style="background:white;"><span>Cheers Alan</span></div></div></div></div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">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"></div><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div><br clear="none"><div>_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">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"></div><br clear="none"><br clear="none"></div> </div> </div> </div></div></div></div><br clear="none">_______________________________________________<br clear="none">
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