Tail servo burn out... twice!

[Gazzer1uk]

Esteemed flyers......

Long story cut short, crashed it..... all back together with new bits and bit of a tail wag.... went high went low on gain, and no difference..... landed, tail servo solid and very very hot.... burned out.... Got a new one, all fine to start, checked smoothness etc..... again, bit of a wag, up and down with the gain, no different results....landed after a couple of hops and servo again burnt out.....

So before I add another one..... what could I look at.... It almost seems that the push rod travel is maybe only 2/3 of the servo travel, so assuming that it could be meeting the end of the push rod travel so effectively stalling... but before the crash it was I thought fine with no tail wag......

Just looking at what to do diagnostically in real terms....

Thanks in advance!!

Gazzer

[trillian]

Unless it is binding very badly or the mechanics are applying a huge amount of drag - it sounds like the servo is being driven at the wrong frequency or running at a voltage that is too high.

[Gazzer1uk]

Thanks Trillian,

Its the same make of the original servo and nothing has changed in respect to frequency/voltage, it doesn't feel like it's binding.....

Partly why I am mystified

Appreciate the response!

Gazzer

[DaveJones]

Thanks Trillian,

Its the same make of the original servo and nothing has changed in respect to frequency/voltage, it doesn't feel like it's binding.....

Partly why I am mystified

Appreciate the response!

Gazzer

Did you go through the flybar set process and set up the tail limits. I’m a VBAR guy so not sure if other units are the same but I would guess you need to set up the max throw limits on all of them. If you haven’t the servo could be binding constantly which might not make it happy.

[Gazzer1uk]

Thanks Dave,

I didn't go through any new set up as it "flew out of the box" so suspected that it should behave the same....... I'll check the instructions just in case it is configurable, but think it's probably limited... never say never though.....

Cheers,

Garry

[Made2Fade]

Gazzer for us that dont know, whats the setup? I presume its just stock?

[Gazzer1uk]

Sorry for tardy response, have been busy working from home.... not got that balance right yet!

So yes entirely stock,

Cheers,

Gaz

[Made2Fade]

Gazzer could you check the voltage going to the servo with a multi-meter? Maybe you damaged it in the crash and now its outputting the wrong voltage due to a damaged electrical component. Other than that to me it sounds like its being driven at the wrong frequency like Sheryl first said.

[Gazzer1uk]

Morning,

Sorry for long waits, I didn't have time to look at it again until over the weekend.

As said before there were no changes made to the type/model of servo or any of the radio gear. The Rx is a Spectrum AR Nanolite 335 and the servo an Elite Rudder servo, but same as came with the model originally..... I therefore doubt that the frequency or voltage can have changed, if the RX was damaged I would expect other issues to be seen rather than this.

So what I did last night, was fit the new servo, then take the control arm off, and ensure I got the furthest travel to the right set and then the push rod and tail linkage at the furthest right position so that wasn't stalling. I checked then that it would also not stall to the left which "seems" to be the case.... so I held it in my hand, opened it up and it all seemed to be good, then I did some rudder changes and after a bit stopped, the servo was still quite cool, though admittedly hadn't had much work to do....

So I'll charge her up tonight, recheck the Tx settings, might just reduce the travel a bit on each end (I'm not 3D so that's not an issue!) and see if all is well.

If anyone has any other thoughts, please let me know!

Thanks all,

Gazzer

[Gazzer1uk]

Hi Team!

Ok, so for the record, it's all good now..... I've had 4 flights and (2 further crashes!) but the tail servo is absolutely fine now!

I think on reflection the problem was binding, both in the push rod freeness.... and the servo travel..... now adjusted at the end of the flight the servo at least appears to be cool.....

It's a bit bloody lively mind, even on reduced rates!

Still its a back garden lockdown flyer and getting me back into flying, so no complaints!!

Thanks for the input,

Gazzer