Man its next to impossable to have a perfect flight on video.

Hypreion extended servo arm users. Please give advice on aileron geometry. Wich hole, outside inside horn? My buddy has lost 3 servos on the same wing do to something weird. I can now know for a fact its not the servo. Maybe not loosening up ballink socket?

Originally Posted by tuck

Man its next to impossable to have a perfect flight on video.

Hypreion extended servo arm users. Please give advice on aileron geometry. Wich hole, outside inside horn? My buddy has lost 3 servos on the same wing do to something weird. I can now know for a fact its not the servo. Maybe not loosening up ballink socket?

Yeah that is mine!! I took all of the linkages apart and really worked the ballinks...I am really trying to figure out what is causing the right wing servos to fail! There is zero binding and the hinge is nice and loose. I will post some pics.

Regardless of the servo he's using, it kind of sounds like there is some binding in the control surface movement somewhere causing the servos to over-amp, or the servos are trying to push the control surfaces past their physical throw limits.

When the servo is disconnected can you feel any binding trying to move the control surface the same way the servo does (push/pull the control rod from where the servo does)? How much of a hinge gap is there?

Originally Posted by bighead93

Yeah that is mine!! I took all of the linkages apart and really worked the ballinks...I am really trying to figure out what is causing the right wing servos to fail! There is zero binding and the hinge is nice and loose. I will post some pics.

Try a different receiver just for giggles, maybe something is going on with the signal or power from the receiver on that channel.... I dunno know, but it's a thought.

SteveT

That is what I thought too...I have built over a dozen of the 3DH planes and this is the first time I have had an issue with a servo. I took every ball-link off and made sure that everything is moving free (nothing is binding). I have the horn right over the hinge gap...the aileron moves easy by hand...all the way to 50+'.

So I did finally get out and fly mine today (one flight before yet another servo failuer) and what a nice plane!! Flies great and was down on the deck hovering on the maiden! Second flight was scary...took off and went into a knife edge...snapped to the right and then the right aileron locked at about 30' straight up...thank goodness I was able to get her down and didn't even drag a wing tip...take a look at the pics and let me know if I am missing something...I have a hard time thinking I had 3 bad servos

Originally Posted by bighead93

That is what I thought too...I have built over a dozen of the 3DH planes and this is the first time I have had an issue with a servo. I took every ball-link off and made sure that everything is moving free (nothing is binding). I have the horn right over the hinge gap...the aileron moves easy by hand...all the way to 50+'.

So I did finally get out and fly mine today (one flight before yet another servo failuer) and what a nice plane!! Flies great and was down on the deck hovering on the maiden! Second flight was scary...took off and went into a knife edge...snapped to the right and then the right aileron locked at about 30' straight up...thank goodness I was able to get her down and didn't even drag a wing tip...take a look at the pics and let me know if I am missing something...I have a hard time thinking I had 3 bad servos

I certainly don't see anything. As long as the "quick connect" (or whatever you want to call it), is turning freely in the servo arm, I see nothing that can cause you to burn up three servos.
I really don't know what it could be other than the receiver, but then I don't know how that would cause them to burn up either, but it's worth a shot. Sure less expensive than a whole plane, or even three servos.

By the way.....be careful on that Quad. I fractured my pelvis, broke one rib and cracked three others, and was knocked unconscious (splitting an expensive Bieffe helmet while doing so) while riding my modified Suzuki Quad racer a number of years ago. The Pelvis, and the helmet (and being knocked unconscious) while racing a friend of mine at Holister Hills, CA. The broken and cracked ribs, while doing about two mile an hour along side a deep ditch (also at Holister). Part of the ditch gave way, and I ended up going over backwards, and having the quad land on top of me. The funny (not really) was that I had gone to buy a rib protector that day, but they were out of my size in the type I wanted, and I had ordered one.

SteveT

Bighead,

I notice you installed the ball link on the outboard side of the aileron horn. The manual and the build thread http://www.rcgroups.com/forums/showp...4&postcount=64 show it on the inboard side (mine is that way). The ball link may be binding against the horn at the +- servo endpoints. You should be able to verify this by inspection. Or hook up a wattmeter and look for current spikes.

One other thing to check....make sure you have enough gap aileron-to-wing-root and aileron-to-SFG. These might be binding the aileron at flight loads.

--
Larry

Try swapping out the servo extension if you have one on there. I recall reading about somebody having an issue with one years ago. I can't remember what it was, but maybe if the power wires were shorting with the signal wire it would burn up the servo.

Hi BigHead, question... Does that servo smell burned? An analog servo like the 225 would take a while to burn up, even if stalled. It's hard to say whether the motor or the op-amp would go first, but the magic smoke stinks(!) How are you powering the receiver/servos? The bec output from the ESC or a separate UBEC? Do you have a voltmeter to verify what voltage is going into (and thus out of) the receiver? It would be odd for an extreme overvoltage to pop just one servo, but in electronics I've seen stranger... G. P. may be on to something regarding the extension, or there might be a solder bridge in the receiver on that channel. Solid DC (of high enough voltage) on the signal wire might kill the servo. Do you have a spare receiver you can try? Have all three servos "gone bad" while you were flying the bird? Vibration from the prop/motor might be bringing on an intermittent problem... Hope something here helps. :-)

Rodger

bighead93,

I have my aileron servo on the 2nd hole on the servo arm and the ball link connected to the side of the control horn thats closer to the servo not the opposite side like in your picture. (I use the radio endpoints to get the recommended throws) Maybe that would make a difference.

Joe

My 2 cents. I think your better off with the ball link as the pictures show. If you put it on the other side it would cause more of an angle.
I agree 100% on the servo extension theory. Don't use really light wire extensions either. That could certainly cause it to burn up. There may be wires broken in your current extension giving your connection but now allowing proper amperage to get to the servo.

I'm using the Dubro heavy duty arms and from the center of the servo to the hole I'm using is 1". I also have my ball link on the outside so the linkage is more linear as yours is.

Originally Posted by 1Radioflyer

My 2 cents. I think your better off with the ball link as the pictures show. If you put it on the other side it would cause more of an angle.

It will be less angle when deflected though. The way it is now, the ball link may bind on the control horn as the servo arm moves the control rod to the side (when close to full deflection).

Put the ball link on the inside of the aileron controll horn

Make sure the EZ connector is not too tight on the servo arm.

But I see the biggest problem is you have to put the push rod through the little hole in the EZ connector Though the way you have it you should have less binding.


Pending weather we will have our club fun fly Sat May 1st at Dr Hook's Come on up

Dennis

Thanks for all the replies! The first servo failed from the first time I sent current to it...took it to my LHS and we found that one of the gears was stripped (no burnt smell). 2nd servo was installed...watt tested again no spikes...moving the ailerons the right side froze at about 20' down. Pushed it gently and it recentered. Tried again and the servo was making some strange sounds and froze both up and down. Swapped for #3. Worked great and ground testing and then for a 6 minute flight. Second flight about 2 mins in it locked up. Scary landing like that but I did it...I am going to swap out the servo extention...I took all the ball links apart a couple of times so the ball moves around easy. We will see what the LHS says about the servo...funny the other 3 have been fine (knock on wood)!!

I will try and get up there again Dennis!

Originally Posted by G.P.

It will be less angle when deflected though. The way it is now, the ball link may bind on the control horn as the servo arm moves the control rod to the side (when close to full deflection).

Very true. I just checked mine at full defection and I have clearance and no binding so I'm going to leave mine the way I set it up. This doesn't mean that it won't bind with others.