Ive gone through two servos is there any other kind of servo that would stop breaking
This is weird... One the guys that I see at the LHS carpet track had the same thing happen to him on his rally in 1 month. Ive been beating this KB for 100+ packs the last 3 months and haven't had any servo issues yet. *Knocks on Wood*.
You can probably get a new spektrun servo? Not sure if you also have to get the receiver and controller as well...
Slash 4x4 & KB Rally
I just lost the servo in my Fiesta tonight and it took the ESC with it. I've already called Traxxas about the ESC but didn't discover the bad servo until after I got home for work and they closed for the weekend. I was hoping the servo was ok, I was going to stuff the Velineon system from the thus far abandoned Bandit drag/land speed project in it.
I think there's the hitec hs81mg, it has metal gears but it's not waterproof.
Signs of a fried servo?
Car turns on normally, the throttle runs the motor fine... But as soon as the servo tries to turn or center, the the esc light goes dim and the motor stops. There's a tiny hum coming from the servo itself. The on/off button on the ESC won't turn the setup off, so I have to unplug the battery to clear the lights. The esc and receiver lights blinking very rapidly red/green when this first went down.
This one's just a couple weeks old and not even been run very hard. :/
Last edited by prototyp; 03-12-2011 at 10:54 PM.
Tore everything down... yup, servo. All's well with my old (internally messed-up but not fried) servo plugged in.
Yay radio/esc/etc isn't dead. Boo, time for servo number 3. These things are VEEEEERRRRRY fragile eh.
servos generally on tear up in these cars for one of three reasons, but most are user error: if you crash into something with the wheels turned, it can blow the gears; if you land jumps with the wheels cocked, turning, it can also strip gears; if you install aftermarket pillowballs and have them too tight, it puts extra strain on the servo and can burn up the motor.
for this size of car the stock servo is actually very stout, and it has been our experience that the people that have servo problems are usually to blame themselves.
but the main problem I see is that people do not turn down the exponential or throw on their controllers, this is covered in your user manual, and I don't know why. because racers do it routinely. with the steering set at maximum it requires the servo to work extra hard, and unless you are running very slowly in a very confined area there is no reason to need the car's full steering potential. on our cars we probably have the steering set to maybe 50 or 60%, and not only do the cars drive better because they don't spin out as easily, but it's also easier on the servos.
Servo #1 has internal position-pot issues... the pot's out of alignment and apparently dislodged enough so the little tab on the pot's shaft doesn't engage with the slot inside the output gear. Every turning event would throw the pot and output gear further out of sync... Seems to be an assembly problem as the inside of the output gear was distorted (overtightening? too long a screw?). Was a little frustrating debugging that issue.
Servo #2 pooped while doing some drifting out on the street. The extremes of turning angle in my RPM hubs is tighter than the rest of the travel; I wouldn't call it binding but perhaps my servo disagrees.
The RPMs are set up fine. In fact, they've worn down a bit and are in need of tightening again. The tightness in the steering rigging is at the outer extremes, outside the servo's normal swing limits.
Anyway, tore down the 'fried' servo. Gears are all 100% fine, and the motor spins up if I crank the position-pot shaft. But it 'crashes' when trying to wiggle just a little bit off center. Also a definite binding when spinning the little gear by hand. Something in there is not happy.
Anyone gotten the wire/motor end of one of these servos apart? Seems to be very tightly fitted...
Set the end points for the steering. Check the transmitter's manual for the 'how to'.