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Jarsalla
07-18-2008, 05:58 AM
Hi

Crash #1

Last evening around six o'clock I took my beaver with upgraded electronics and prop to a nearby field. It had had two succesful test flights after I had cut in ailerons a week earlier. Connected the battery and only checked the ailerons and motor if they were working (mistake #1):red: Tossed her up and I thought "wow this prop takes her up vertically....oh what's this why won't she respond to elevator"? Result, nice loop head first to gravel road, bent shaft, broken prop and stick mount pointing up. Brought her back home fixed it for 2 hours and found out that I had forgotten to plug the servos into Rx after I had played with ailerons.:o

Crash #2

I took her back the same day, checked that servos were connected and motor worked. Tossed her up and realised that aileron controls were reversed, brought her safely down and reversed channel number 1 (mistake #2):red:. i did this carelessly, because I previously had ailerons on channel 1, BUT I had just recently switched them to Channel 4. I did check the if the ailerons were working, they did,but still reversed....:roll:

Tossed her up once again and realised that ailerons were still reversed tried to bring her back down, but a tree beat me to it :blah: Luckily she came down on her own. When I was going after it, I put my Tx hanging on my shoulder and walked torwards her (mistake #3):red:. When I got nearer I heard that motor was mowing the lawn, checked my Tx and found out that the stick had moved and turned on the motor. :blah: The motor had grass and hay twisted on its shaft.

So after this very eventful evening I took her home and dissembled the motor and found out that it smelled a bit burned and saw two magnets or something, a bit black (picture). Though the motori is still working I think it's skipping those two black ones, eventhough I didn't notice it during test run.

BTW I noticed that the plane drug its tail and tended to go up, eventhough the elevator was trimmed. CG should be just about right, but is this because the motors angle of attack wasn't downwards enough?

Ok I'm out to order a new brushless.

clockworks
07-18-2008, 07:17 AM
The black marks inside your motor look like they were made in the factory with a magic marker (felt tip pen), rather than damage. Try wiping them off with alcohol or thinner to check.

Lymph
07-18-2008, 07:22 AM
yep, looks like a factor drawn mark with a texta.

Jarsalla
07-18-2008, 07:24 AM
The black marks inside your motor look like they were made in the factory with a magic marker (felt tip pen), rather than damage. Try wiping them off with alcohol or thinner to check.

That's what I thought aswell. I'll try that when I get home. My ESC has an automatic cut off if the motor is stalled by an object or drawing a lot of current over 2 seconds. The motor smells a bit like burnt electronics though.

Nonetheless I ordered a new motor, they are only $9.95, so it's nice to have reserve. Hopefully my wife will think the same :D, I'll have to buy her something aswell.

clockworks
07-18-2008, 07:28 AM
The burning smell is probably just the varnish/laquer used to insulate the windings. It smells if it gets too hot, but hopefully no real damage. You can test for failed windings with a meter. Disconnect the motor wires and measure the resistance across each pair of wires. If they are all more or less the same, the motor is OK.

Jarsalla
07-18-2008, 05:14 PM
I wiped the marks with thinner and it vanished, so it was magic marker. The motor works fine, I even managed to straighten the shaft so that there's virtually no vibration at all. Elevator is epoxied on, but cowl is still missing. I'll have to replace it, because it's so battered.

Jarsalla
07-20-2008, 05:22 PM
Over amped the motor yesterday with a 10x4.7sf prop, puffed smoke and eventhough I used WOT very briefly. Didn't crash her though.

http://www.youtube.com/watch?v=1eqHl9VWnaw

1eqHl9VWnaw

GreenAce92
07-20-2008, 05:37 PM
heheh nice stunt beaver, sorry for your crashes, glad you got it to work out.

Jarsalla
07-20-2008, 05:54 PM
heheh nice stunt beaver, sorry for your crashes, glad you got it to work out.

Yep, but then the motor blew up :roll: