RunRyder - Tail WAG!

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e-E-Sky Honey Bee- Lama- Belt CP- E-Smart > Tail WAG!

jmc67
Senior Heliman
Location: Westchester County, NY

Recently changed the belt and tail shaft and now I am getting a nasty tail wag. Before changing both, there was no wag. Nothing is binding, gyro (gy401) gain is set to 65% in HH mode as it was before. Belt is not tight. Now when I'm using normal throttle tail wag is non-existant. However in idle1 there is some wag, idle2 much worse wag. Setting the gain to a lower setting does not stop the wagging.

Normal throttle at is: 0-30-80-85-100. Pitch is -2/+10 in normal mode.
Idle1 throttle at is: 100-90-90-90-100. Pitch is -10/+10.
Idle2 throttle at is: 100-100-100-100-100. Pitch is -2/+10 in normal mode.

The brushless motor used is the esky 3800 with a 9t pinion, on the tail, I am using the trex 450 rotor blades.

Help is greatly appreciated.

12-17-2007 07:07 AM

shizack
Veteran
Location: Augusta, GA USA

Well ,you've been dubbed a "Senior Heliman", so I hope I'm not suggesting something you already did.

Have you checked the new shaft for bulginess or burrs ("fat shaft" syndrome)? Moved the unattached-to-servo control rod to check for smoothness?

This does sound directly related to HS, though...hmmm, higher headspeed, move vibrations...

Did you bump the servo during surgery and maybe loosen the tape's grip on it? Maybe add a zip-tie...

Did you lube the new shaft and maybe get some under the blade-holder's grub screw?

Maybe play around with rudder expo or dual rate to see if that helps...

That's the only non-obvious stuff I can think of right now...

Ooh! Before I "submit" - are the rudder expo and D/R set the same in the TX in all three flight modes?

Just because you're paranoid doesn't mean they're NOT out to get you...

12-17-2007 08:13 AM

HOMEPAGE

DougsRC
Elite Veteran
Location: MA

It's almost always been my experience that when it wags the gain is to high. Especially in idle up where your mainblade pitch is lower relative to your headspeed. There has to be a point where when you turn the gain down it won't wag anymore. Keep turning down the gain until it stops wagging or if you don't want to do that, another thing you can try is moving the ball link on your servo arm closer to the servo, it gives you less throw on your servo and allows for higher gain on the gyro. Another thing I did when I first got the King was remove the tail rotor push rod guides, there would occasionally be some binding. Let us know what you discover!!!

12-17-2007 10:31 AM

tryan02
rrProfessor
Location: Canton, Missouri

So thats what those little black clips on the boom are for.

I popped the control rod out of them when I first got the heli as a noob I could tell that wasnt right. I am running 65% on my 240 I seen wag anywhere higher. I will get a little wag on the end of the battery pack I blame it on the BEC/ESC I should go separate but im cheap.

Canton MO backyard flying club
Club President
Team No funds left.

12-17-2007 05:57 PM

HOMEPAGE

jmc67
Senior Heliman
Location: Westchester County, NY

shizack, everything you suggested was done prior to posting here. All settings are the same. Nothing was changed prior belt and tail shaft change.

DougsRC, prior to changing the belt, the gain was set to 65% with no wag effects. I set the gain to 40% and wag was non-existant but then I would have almost no tail authority. The ball link on the servo arm is as close to the servo as I am going to get it. I am going to try a different servo and see what happens. The tail servo I currently have installed is the HS-50.

12-17-2007 05:58 PM

jmc67
Senior Heliman
Location: Westchester County, NY

Update: Those of you who have dis-assembled the tail (stock), did you have shims other than the 2 step washers? Looking at the manual there is no mention of this but only the step washers. I ask because, I had these shims on my tail and now I am thinking this might be the culprit to the tail wag. I also checked the package and there are no shims.

12-17-2007 07:58 PM

DougsRC
Elite Veteran
Location: MA

I think you are on to something. There should be some washers keeping the tail shaft from shifting side to side without binding.

12-17-2007 09:08 PM

jmc67
Senior Heliman
Location: Westchester County, NY

The washers based on the manual should be the step washers one on each side. These other washers (shims) should not be there. I am about to take apart the tail so I can remove these extra washers.

12-17-2007 10:58 PM

tryan02
rrProfessor
Location: Canton, Missouri

friction was the killer huh? I haven't had my tail apart yet I'm trying to visualize your problem for future reference. thanks for sharing

Canton MO backyard flying club
Club President
Team No funds left.

12-17-2007 11:59 PM

HOMEPAGE

jmc67
Senior Heliman
Location: Westchester County, NY

Success!?!

First and foremost, those extra shims were not suppose to be in the tail shaft assembly. Well, I think I fixed the problem. There was some slop in the tail grips which holds both clamps together and I also had to tighten the screw that holds the tail rotor control arm just enough to remove the slop but not too tight that would case binding. I am going to do one last check tomorrow after I recharge all 3 lipos.

Is there an alternative cnc tail rotor that can be installed on the King2 besides the one from esky?

12-18-2007 05:48 AM

shizack
Veteran
Location: Augusta, GA USA

I believe the HDX300 tail box is compatible with the King.

Just because you're paranoid doesn't mean they're NOT out to get you...

12-18-2007 06:11 AM

HOMEPAGE

DougsRC
Elite Veteran
Location: MA

The HDX300 would most probably work fine, a little pricey. Slop in the tail, I can see that creating a WAG, I HATE SLOP. I was running a TREX Clone tail for a while till the pitch slider got damaged in a crash, A CRASH !

Yes a crash, they do happen! But anywho, the boom diameter is bigger so you have to use a bushing of sorts to fill the space.

12-18-2007 12:21 PM

Gregor99
Key Veteran
Location: Western Wa

Quote
First and foremost, those extra shims were not suppose to be in the tail shaft assembly.

Mine came this way and I always wondered what the correct assembly was supposed to be since the extra shims aren't in the manual. Interestingly, I've also had a tail wag since the heli was new. I recently discovered both tail bearings were a little rough. One side was much worse than the other. After cleaning and re-lubing the wag is better, but not gone. Both bearing's smoothness did improved, but one is still sandy in one spot. As soon as I get the replacement bearings, I'll try it with and without the shims.

12-19-2007 04:17 AM

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e-E-Sky Honey Bee- Lama- Belt CP- E-Smart > Tail WAG!

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