Sunday, May 13, 2012

Blown Motor

Recently I got a little ambitious and decided I wanted to fly my Wild Hawk in the wind again.  We  had a few good days of wind and I got my opportunity on a recent Sunday.  My oldest daughter is home from college and she graciously offered to spend some time with her dad and be my film crew.

We headed out to the nearby park that I like to fly at and setup for a windy day of flying.  We were all set to go and then this happened (see the video below)

Not but a few seconds in the air and the motor suddenly quit!  My big head gets in the way so you can't see the crash landing.  Fortunately it is spring and the local growth in the wild life area is about three feet high so, no damage at all.

After retrieving my Wild Hawk, I tested things out and the following video shows what I found.

You can see that the motor would do little more than stutter around and mostly not turn.  I was so disappointed because this meant that most likely I was buying a new motor.

Time to take this plane back home and check everything out.

Testing the ESC
I  suspected that the motor was at fault but the first thing that I did was to check the speed controller with another motor, just to make sure.  This picture shows another motor connected as well as my servo tester.  This test showed the speed controller to be working just fine.

Now I have to dig into the motor itself to see what is going on.  I started by taking it apart.  This was easy and just required the removal of a snap ring and the can with the magnets just slipped right off (OK, I had to tug pretty hard to get past the magnetic pull).  I then gave it a good inspection looking for obvious problems like broken or shorted wires.

Problem found
Since I did not find anything obvious, I then used a multi-meter to test the windings.  I had continuity between the black and yellow wires but not between the red and any other wire.  This meant that there was and issue with this part of the wiring.  After some closer inspection (this included the high tech method of tugging on the wires and connections), I found that the bullet connector had a cold solder joint and actually pulled right off (yeah, tug test found this one).
The repair

This merely required the correct application of heat and solder to fix.  I also found it helpful to make sure all of the heat shrink was where it was supposed to be before I got too far.  Next time I'll be more careful with this.

Any way, this fixed my problem and within 30 minutes my daughter and I were back out at the park and flying in the wind.  See my next post for that experience.

As usual, thanks for stopping by my blog and please post comments, good or bad.  Be sure to come back and check for future posts.