Endbell Heat Sink

[Shooter]

Haven't had a lot of time to post results, but I can say that I have just under 30 runs with the 1717 prop with no signs of temp issues. That's significant if you ask me. I've been running a solid 54mph (55.8 max recorded). No side by side temp data with and without heat sink, but we have randomly taken temps AT THE WINDINGS, NEAR THE WIRE EXIT and they were fairly high (140°F) with the sink (typically after 7 laps). We've taken the sink off several times after runs and it's H-O-T!! I believe it is really beneficial during the after run heat soak as well.

Gotta work on the turns now! The guys in our club can really carve some water, and I can't touch 'em, even with these speeds.

[Brushless55]

Awesome news man!!

[ray schrauwen]

Nice work man!

May I ask the OD in case I try to lathe/mill one up? Length?

YOu know China will start pumping these out eventually if it catches on.

[Shooter]

Thanks.

Ray, it's 43mm diameter x 23mm length. Nothing special about it though. Would be nice if someone started making them though. Seems to help save the motor. Since the motor is tilted, I bet a lot of the heat at the end of the run goes right to the endbell.

BTW - I ended up moving my motor Waaaaayyyy up front. A bit controversial because of the flex length addition and the 's' bend since I kept the old hole. Seems to work and the speeds are still good. Layed my batt up front sideways for even more weight up front. Raced this Sunday with no additional weight added. We had some heavy gusts in one of the heats, and she kept on the water.

I guess any fool like me can put a big prop on a boat and get it to scoot. I'm sure someone that knew what they were doing could get another 2 or 3 mph out of this thing!

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[properchopper]

Quite an impressive bit of fabrication - nice job ! As a "fan of the fan" I can't help but wondering if you could get more heat extraction out of the design by mounting a small fan on the fins sucking air through the fins away from the endbell which will quite possibly further drop temps. As it is, it's a really nice piece.

Still a little curious about complying to the NAMBA rule of leaving the motor "as delivered from the manufacturer" So far I'm skirting the rule by having a small fan blowing on, but not attached to the motor.

[Shooter]

I agree. Adding a fan will most definitely increase the efficiency of the sink.

As for the NAMBA rule, I'm not modifying the motor, only clamping to it (similar to the water jacket). The first design in post one threaded into the endbell, which is clearly illegal since the motor would not be "as delivered". The intent wasn't really to modify the motor, but rules are rules. With the clamp however, the motor is still "as delivered". No modifications to the motor.

The rule also states that we can add "water cooling"....so I guess to gaurantee compliance, we could run a brass water line through it and call it done, but I still think it complies without it.