Rick
08-19-2006, 05:14 PM
I used to race (informally) an old MRC Miss Budweiser/Mr. Pringles electric hydroplane during high school. Originally powered by twin 540 Mabuchi motors and two six cell NiCAD packs thru a mechanical speed control, I upgraded it to twin AstroFlight 05 cobalt magnet brushed motors, twin seven cell packs, and an electronic speed control.
Wasnt too bad but the drive gear was too weak to handle a larger prop and the stock prop cavitated too badly to give any serious speed boost. I welded one set of battery connectors together until switching to silver contact sermo's. Sadly I didn't understand the wattage draws of having too small a prop and a few other issues.
Ive been kicking around the idea of building a catamaran powered by a large outrunner brushless, fed by a big thunderpower pack-esesentially running the same speed control and motor setups the big scale electric planes in the kilowatt class use. Running gear would probably be a flex shaft to outdrive system for a gas boat, using the pickup tube to water cool the motor.
Methinks the much lighter weight of modern LiPO's and the greater torque and RPM range of a good brushless would allow a kickass direct drive setup that would absolutely *scream*.
Wasnt too bad but the drive gear was too weak to handle a larger prop and the stock prop cavitated too badly to give any serious speed boost. I welded one set of battery connectors together until switching to silver contact sermo's. Sadly I didn't understand the wattage draws of having too small a prop and a few other issues.
Ive been kicking around the idea of building a catamaran powered by a large outrunner brushless, fed by a big thunderpower pack-esesentially running the same speed control and motor setups the big scale electric planes in the kilowatt class use. Running gear would probably be a flex shaft to outdrive system for a gas boat, using the pickup tube to water cool the motor.
Methinks the much lighter weight of modern LiPO's and the greater torque and RPM range of a good brushless would allow a kickass direct drive setup that would absolutely *scream*.