I need some help to find "cooling coils" for my motor. Even better........ the correct material and source to get it. My motor is 2 inches, (4 cm), in dia, and I cannot see any coils that big to fit this motor. Plus, all the materials I have seen to make one are way to hard to bend, or too small in diameter to work correctly.
Thanks,
lownslo....... Bob in Indy

Get yourself a 3' length of K&S aluminum tubing with an ID of 1/8". Then do a standard wrap using your favorite technique.

Or you could try www.offshoreelectrics.com - they have a forum where you can ask, if you can't find it in the catalog.

Andy

Crimp shut one end of the tube, fill tube with salt or fine sand, pack tightly, crimp other end of tube... and 'wrap'...

Hi Bob,

Like Andy says, the coils are easy to make yourself, an even more effective addition would be brushtab cooling; a piece of brass tubing soldered onto the brushtabs of your motor.

I'll add a few pics to illustrate.

If you're interested, I have a 'how to' and pics of the brass sheet cancooling in the first picture, let me know if you want it.

Regards, Jan.

That's some pretty sweet work, Jan!

Thank you fellas for your replies!![8D] I went back and edited this because I forgot to ask: My boat is a Sea Queen with a stock motor that comes in the kit. They say it is a 3000 rpm motor, 12 volts, 3 blade 50 mm prop. I doubt if speed will be real good with this set up but right now I am "maxed out" on spending. I may change power later.
Will I need a pump for the water cooing, OR will the pickup in the prop wash be enough for cooling?
lownslo.

Hi Bob,

As mentioned in other Sea Queen threads, the stock motor and prop will get you going, most likely at scale speed or a little faster.

If you intend to go (much) quicker, you have to look for a more powerful motor that will fit in the same mount as the stock one (a Graupner 900 motor, just to mention one), or make provisions during the build to have the possibility to upgrade to a larger motor with more torque, but not significantly higher ampdraw.

I've added two pics to show what I mean:
The first two motors are surplus copy machine motors, high torque, low ampdrawing motors, about the same size as the fan motor in the next picture.

Source for the fan motor: scrapheap (it doesn't get much cheaper).

I recently replaced the ugly copper cooling coil with a cooling jacket like the one on the 700 motor, to keep the diameter down, I added some pictures of the new jacket.
The motor next to the fan motor is a 900 Johnson, for size comparison.
The fan motor will power my 43" MTB on 12-24 NiMH cells.

You see, these industrial motors are rather big, so you'll have to adapt the motormount during the build, to be able to use one.

Expect runtimes like with the stock motor, but you'll be able to run a much bigger/coarser pitched prop, making the Sea Queen jump on the plane in a matter of feet when you punch the throttle...

A propwash pickup will provide ample flow for motor and (if required) ESC cooling.

Regards, Jan.