• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.

need a little help with troubleshooting (I think it might be something i did)

etofun

Junior Member
#1
hi all, so long-story short, i making my first tricopter (first flying thing for that matter), i went with the bat-bone and everything the flite test guys listed as recommended, except i got 1600Kv motors instead of the 1380Kv since hobby king was out of them and i hadn't done much research up till that point on airplane motors(I'm used to Ground RCs and normally Kv just mean rotations per volt, i didnt know about prop sizing or anything like that). so 15amp turingy multistars, 1600Kv turnigy park300s, kk2 lcd, and 8 x 4.5 props. so, enough of that here's the problem im having-

one thing i also noticed is it seems like the motor are pulling different amounts, it seems the front left motor pulls up its corner first. in self leveling it less noticeable but still there, without its downright bad, like flip over instantly or needs a bunch of stick input bad. i check the gyros and they were all compensating in the right directions, i tried increasing the p-gain and limit on the self leveling to no avail.

so here are a few of the things i think might have caused it-

funky wiring harness

526404_651805868164322_821595505_n.jpg

the male dean in the top corner connect the battery and that goes down to female deans that connect the ESCs. i had no bloody idea how to wire this thing so i winged it, and it kinda shows.

motor to ESC wiring

970142_651805904830985_294502154_n.jpg

this is just embarrassing but i didn't have enough bullet connectors. i thought i did, but i didnt. so i soldered the yellows together, and put the bullets on the red and black so i could reverse rotation if i had to.

motor damage

999811_651807878164121_1190214586_n.jpg

this actually isn't the first tripcopter frame i've tried, i got a cheap Chinese one from a friend so i ordered the electronic stuff and tried to fly it. i still had self leveling problems and ended up crashing it hard, it hit the motor and broke a carbon spar. it seems to spin okay and the shaft dosen't seem bent when i run it up.

i also kinda ordered in haste, i want to FPV with this thing, but i also want to do some filming along the lines of stuff like chasing the cars around the local autocross course. i heard David talking about hobbyking plush ESCs on one of the vids, so at least from what i kinda understand to be able to haul this thing around and change directions fast i would want a lower KV motor and a biggerprop.

anyway, enough rambling on my part thanks in advance for any help i can get, cheers.
 

FlyingMonkey

Stuck in Sunny FL
Staff member
Admin
#2
A quick checklist, (off the top of my insomniac head...) some of the things you've already mentioned you've checked...

Re: Uneven lifting of the motors.

Have you calibrated ESCs?
Make sure you have the propellers on in the correct direction.
Make sure the motors are spinning in the correct direction.
Are the wires to the board/receiver in the correct positions?
Did you zero out the board to reset level?

If you haven't seen them, the videos in this thread are very helpful.
http://forum.flitetest.com/showthre...shing-his-multi-quot-Thread&highlight=patrick
 

etofun

Junior Member
#3
I calibrated ESCs, Propellers were all turning in the right directions with the little words up, motors all spinning correctly, double checked all the wires - all good, and I tried restting to factory a couple of times. i check out the thread tomorrow since its 1 AM here and any info i may come across probably wont stick
 

Cyberdactyl

Misfit Multirotor Monkey
#4
Are your ESCs exposed? I mean is there any kind of shrink on them? If not, that's a burnt ESC waiting to happen. The heat sinks can slide around under zip ties kind of easy.

But other than what Flyingmonkey said, I would list the pertinent settings on the KK2 for us. Also, I'm pretty sure this is not your issue, but have you checked your 'Minimum Throttle' under 'Misc. Settings'? You might want to put it on around 15-20.
 

earthsciteach

Moderator
Moderator
#5
Did I hear you say you had a crash? I wonder if you have a loose solder connection or a broken winding wire on that motor. Did you epoxy the motor pigtail per David's recommendation prior to the crash?
 

etofun

Junior Member
#6
yeah the heat-shrinks are off the ESCs, i didn't epoxy the motor wires cause i got the turingy parkfly ones, i thought they didn't need it. i think i did a factory reset before i gave up for the night but ill go through and list the setting later(quick post before work). if there is damage like a broken wire to one of the motors, is that repairable?

i also forgot to add last night, yesterday i was trying to hover it on my lunch break and maybe halfway through the pack i noticed that the motors were quite hot, like a very uncomfortable to touch but not painfully hot.
 

etofun

Junior Member
#8
I think that may be the case, the chinease frame was hovering okay but seemed to get worse and worse until it broke. i did have one kinda bad crash with the batbone frame and it seemed like after that the rear started acting up too. i also checked what my setting were, and they were factory. i did a reset to be sure. welp is that something i can repair or are new motors the way to go?

ill also make it a note to do the epoxy thing to any motor for here on out.
 

xuzme720

Dedicated foam bender
Mentor
#9
The "epoxy thing" is usually just for bell type motors or motors where the wires are not supported/protected by the motor case.
 

etofun

Junior Member
#10
ahh, okay. i dug deeper tonight. the wires from the motor are broken on the rear and front right motors, the really bad one is in the motor and the rear was just at the solder joint. seem like these wires are literally just one thin piece of copper, is that normal? that seems really fragile for something that might have to endure some abuse. im guessing the one thats broken internally cant be fixed so looks like im in the market for a new motor.

999559_652492431428999_1054896523_n.jpg

this is the one with the messed up bell, sooooo :p
 
Last edited:

etofun

Junior Member
#11
can i keep asking question in this thread? i dont want to start littering the forum with useless thread everytime i have a question.

im still struggling to wrap my head around the whole prop sizing VS. motor sizing thing. from what i think i understand a big KV + small prop = high air speed, but less torque so more sluggish at changing it's speed, low KV + big prop = less air speed but a more torque response. so if i wanted to build a copter that can change direction quickly i would want the more torque setup? or am I over thinking things again?
 

Cyberdactyl

Misfit Multirotor Monkey
#12
Stator wires that have been broken where they exit the motor can generally be fixed by unwinding three or four turns and VERY carefully have a small wire soldered to them. Then coat VERY thinly with epoxy. I have used the wires out of monitor video cable. It is around 28 gauge, and the insulation is very thin. . .almost perfect for the task. :)

When a motor is trash would be from a crash where the bell is dented or the stator wires have impacted something and many are severed, or the motor has been heated to where the wire insulation has burned or melted.

As to prop size, yes small is quicker and large has more lift but more sluggish.