I need some smart guys... help.

I've stripped the (only) plastic gear in the JR8611A servo no less then 10 times this season. These are ganged on the wings of a 35% H9 260 with (currently) Equalizer IIIs.

I replaced the Equalizer IIs with the IIIs after 4 occurances. I'm still having the servos stripping the plastic gear.

Just bought an Amp meter to see if could possibly be so far off on my setup (centering and end point) that I am causing the problem in set up. It ain't the case... matching the servos manually and listening for binding proved nearly as reliable as using the AMP meter.

Is there any possibity my four Equalizers are causing the problems? It doesn't seem likely to me but I can not figure out what the problem is.

I just had Horizon send me a dozen B4 gears...
... help!

Got a friend that has the same plane and servos. Found out at Joe Nall this year some of these planes the aileron would flex some. Mike Mcconville said to up grade to 8711 servos and problem will go away.

look into aileron flexing. has caused me and others issues with stripping or damaging servo's. look into the 8711's or maybe 8911's. what i have done was stiffen up the aileron on my plane. stripped off the bottom covering on the outer half and fully sheeted the bottom aileron. so much stronger now.

... <<shrug>> ...

On 6v, the 8611a servo is rated at 320 oz. The prevailing thought is the aileron 'flexing' is occuring to an extent that it exceeds the rated capacity of 8611a servos to withstand? What?! Really...?

I'd think these servos should rip the block and screw right off the ailerons on this airplane. The spec is for metal geared servos of 180 oz in torque. The manual specifically states 8611A servos meet or exceed the requirements.

This airplane... I was an original owner, lost the first one at an IMAC contest in Browns, IL... catostrophic right wing failure. Received a replacement no charge... and am grateful for it. Very nice of Horizon to do it... thank you. The wings on the replacement airplane... BAD TOO... had to be replaced. Now recieved "V2" wings... and the aileron is FLEXING?! To the extent its strippin' 8611As?!

I'm Done.

Originally Posted by falcon_az

... <<shrug>> ...

On 6v, the 8611a servo is rated at 320 oz. The prevailing thought is the aileron 'flexing' is occuring to an extent that it exceeds the rated capacity of 8611a servos to withstand? What?! Really...?

I'd think these servos should rip the block and screw right off the ailerons on this airplane. The spec is for metal geared servos of 180 oz in torque. The manual specifically states 8611A servos meet or exceed the requirements.

This airplane... I was an original owner, lost the first one at an IMAC contest in Browns, IL... catostrophic right wing failure. Received a replacement no charge... and am grateful for it. Very nice of Horizon to do it... thank you. The wings on the replacement airplane... BAD TOO... had to be replaced. Now recieved "V2" wings... and the aileron is FLEXING?! To the extent its strippin' 8611As?!

I'm Done.

Wow! Very Interesting. Keep us posted.

Different servo probably wont help. Change the linkage mechanics to give the servo better mechanical advantage. Simply lengthen both horns a little bit (or move in a hole on the servo arms). You'll loose a little total throw but there is plenty and the servo's load will be less. Should work. Did on one of my own 260s what was stripping an outboard servo.

Originally Posted by mmcconville

Different servo probably wont help. Change the linkage mechanics to give the servo better mechanical advantage. Simply lengthen both horns a little bit (or move in a hole on the servo arms). You'll loose a little total throw but there is plenty and the servo's load will be less. Should work. Did on one of my own 260s what was stripping an outboard servo.

I'm have been having the same problem on a 40% Carden 300 with 8611's, I have tried lots of things but nothing has worked. I'm setup with Imac rates at 3/4" on the servo arm and about 1-1/4 on the horn and I keep stripping outboard servos. I had a Carden 330 that I flew for 5 yrs with 8411's on the ailerons and did not ever strip a gear.

Keith

Here is a curve you probably don't see coming.

I asked Horizon to send me the B4 gears, they did... no charge. Very nice.

I was taking the stripped B4 gear out when I started to inspect the grease. The grease had fragments from the stripped plastic gear in it. So... I've thoroughly cleaned and regreased them - will test fly tomorrow. I believe the fragments were getting in the plastic B4 gear and breaking teeth off. That gear spins like mad... can easily see this happening.

The linkage is setup identical to the previous 260 (or very, very close). Didn't have this problem on the version 1 wings. However, if they strip this time... I'll definetly change the linkage. Thanks Mike!

I think you may have just solved the issue buddy! Good luck!!!

Originally Posted by falcon_az

Here is a curve you probably don't see coming.

I asked Horizon to send me the B4 gears, they did... no charge. Very nice.

I was taking the stripped B4 gear out when I started to inspect the grease. The grease had fragments from the stripped plastic gear in it. So... I've thoroughly cleaned and regreased them - will test fly tomorrow. I believe the fragments were getting in the plastic B4 gear and breaking teeth off. That gear spins like mad... can easily see this happening.

The linkage is setup identical to the previous 260 (or very, very close). Didn't have this problem on the version 1 wings. However, if they strip this time... I'll definetly change the linkage. Thanks Mike!

Originally Posted by mmcconville

Different servo probably wont help. Change the linkage mechanics to give the servo better mechanical advantage. Simply lengthen both horns a little bit (or move in a hole on the servo arms). You'll loose a little total throw but there is plenty and the servo's load will be less. Should work. Did on one of my own 260s what was stripping an outboard servo.

Rainy couple days so I haven't been able to fly. Decided to change the linkage... moved in 1 hole on the arm. Your right... it didn't change the throw much at all. Was easy to to change the rate and get exactly the throw I have been using.
Cheers

Well the problem is solved. Flew 1 1/2 gallons yesterday... several flights... no servo problem whatsoever.

I'm positive the plastic gear debris left in the grease, when the servos were serviced, caused this on-going fiasco.

Because I changed the linkage at the same time - this too must have had a positive impact (though I'm not sure, but don't intend on changing back to the original setup to verify).

Thank goodness this is over.