<html><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_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21360">Thanks Hank & Graham.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21357">I am probably searching for Nirvana here.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21353">First I am set on finding a brushless motor solution.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21358">I spent multiple hours of Googling, focusing on E-bikes, scooters etc.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21411">The E-bikes are mainly hub motors that are narrow with a large diameter, which</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21410">is no good as far as drag is concerned, plus you need a big prop to get out beyond</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21405">the diameter of the motor. There are units with 5-1 gear box ratios at 48V 1500W</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21409">but they can weigh around 14kg. I bought an 1850W Hobby King BLDC outrunner</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21434">motor for $56- & it weighs 530 grams. So more powerful & 1/27th the weight.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21488">This does 236 rpm per volt, & from what I've read you don't want to be turning your</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21502">prop at more than 3000rpm on a sub. This means I would have to drive this motor with </span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21554">a maximum of 12V & it's rated for a maximum of 37.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21541">To disipate the heat from the stationary inner coil of an outrunner, I may be forced to</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21540">go with oil compensation; which is what most commercial brushless thrusters are anyway.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21555">One solution I can see is to go with a much larger hobby type motor & run it way below</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span>it's maximum voltage to keep the revs down. Also I wouldn't be thrashing the motor</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span>which may help it live a lot longer.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21602">Need to do a lot more study here, then experimentation with motors & props in water.</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span>Alan</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span id="yui_3_16_0_1_1414692316074_21603">P.S. Hank I was given a motorized Golf trundler & converted it to a trike with ape hangers</span></div><div id="yui_3_16_0_1_1414692316074_21297" dir="ltr"><span>and pink banana seat for my girls. Boy did they love showing off on that.</span></div><br> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1414692316074_21302"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1414692316074_21301"> <div dir="ltr" id="yui_3_16_0_1_1414692316074_21300"> <hr size="1" id="yui_3_16_0_1_1414692316074_21299"> <font size="2" face="Arial" id="yui_3_16_0_1_1414692316074_21303"> <b id="yui_3_16_0_1_1414692316074_21356"><span style="font-weight:bold;" id="yui_3_16_0_1_1414692316074_21355">From:</span></b> hank pronk via Personal_Submersibles <personal_submersibles@psubs.org><br> <b id="yui_3_16_0_1_1414692316074_21352"><span style="font-weight: bold;" id="yui_3_16_0_1_1414692316074_21351">To:</span></b> personal_submersibles@psubs.org <br> <b><span style="font-weight: bold;">Sent:</span></b> Friday, October 31, 2014 1:32 AM<br> <b id="yui_3_16_0_1_1414692316074_21425"><span style="font-weight: bold;" id="yui_3_16_0_1_1414692316074_21424">Subject:</span></b> [PSUBS-MAILIST] Alan needs a motor<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_1_1414692316074_21304"><br>Alan,<br>I just went on ebay and found a 1,000 watt 48v brushless motor with controller for 200 dollars. It is for an electric bike. I bought one for my son a few years back and it was amazing. He was driving it all over town and towing his buddy on his skate board. Just type in brushless 48 v motor.<br>You won't need a gearbox either.<br>Hank<br>_______________________________________________<br>Personal_Submersibles mailing list<br><a ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org" id="yui_3_16_0_1_1414692316074_21309">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank" id="yui_3_16_0_1_1414692316074_21305">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br><br><br></div> </div> </div> </div></body></html>