Thread: Discussion Cheap fun boat?
View Single Post
Old Apr 21, 2012, 06:00 AM
KiwiDavid is offline
Find More Posts by KiwiDavid
Registered User
Joined Jun 2011
263 Posts
Hi,
All done! Conversion complete......after stealing the receiver and controller off my Brave Class fast patrol boat.

I've attached the last pic of the motor before it went back in to the boat. The big thingy across the motor is an old ultra fast diode. I normally put an axial mount 8A Schottky directly across the motor terminals (no reverse) but had run out of them so this will have to do until the motor upgrade. The electro cap I spotted across the motor was a 47ufd, 16V non-polar cap. Have never seen this before.

To change the motor I have to open up the gearbox as I think it's screwed on from inside the box. Will leave this sticky job for another time.
Running the motor at low speed there is a bit of vibration from the outdrive and I get the feeling the shaft coming out of the transom is a little too high to line up with the drive itself. I may be able to get a little movement but not much and I'm still learning about these things.
At full left or right rudder the motor also slows down when running at low speed but I would expect a universal to present more friction at higher angles.

The little circuit board in the pic is my PWM controller. It uses a single 3milliohm fet and I've used it on motors with stall currents up to 60A without problems. It's very cheap but has most of the features of a brushed controller - one off Tx learn mode, parameters stored in EEPROM, low battery indicator (cuts power to about 1/3rd), throttle inertia (for big boats) and loss of signal failsafe.

Will head off to the lake tomorrow again and hopefully freeing up the shaft will see an improvement in speed. I know the handling will be better with proportional steering.

Cheers,
David
KiwiDavid is offline Find More Posts by KiwiDavid
Reply With Quote