Tail Wag Cures

[eddiepierre]

Hi guys!!! Right, for weeks and weeks I've been having tail wag issues I had tried nearly every single mod/fix I could find on this and every other forum! Nothing but nothing would make it completely go away, 1 plus point though I have learnt how to manipulate and tune mechanical and electrical settings like I never thought I could, so close to tuning out the dreaded "wag" but never quite getting there..... My last resort was a "microheli" tail,,, having had 1 fitted to my 450pro I came to the conclusion that I never wanted anything else to do with very poor workmanship and Ali so soft it bends just giving it the evils? Anyway I'd read a few good reviews on tail for the 250, what else had I to loose? Trip to lhs sore me part with £47 wow I initially thought, but on reflection not much difference to buying a full align tail assembly, back home literally 20mins to fit I tentatively tuck it for test fly,,, HOORAY,,,,,,, that bloody wag finally gone,,, so I started re-tuning electric and mechanical settings now I have a Heli I am so happy with,, ps, hope this helps somebody, also please do not under estimate the lengths I had gone to in getting this Heli to behave for me,,,,

[Designbydave]

Thanks Eddie. I'm running the microheli flybarless head so I may give the tail a try.

I am experiencing a bit of wag, its not so bad that I can't fly the heli but its a bit annoying. Its inconsistent and when it happens it only wags back and forth a couple times and steadies out. Yesterday I crashed it (experimenting with gyro sensitivity and set it too low, lost control, tail slid into the grass. Pretty much only broke the tail boom and one of the support braces. I decided to rebuild it with the carbon fiber tail blades because they look cool. Next test flight had way too much wag, even in a hover. Adjusted the belt tension but that didn't help. Swapped back to the larger plastic bladed and I'm back to where I was yesterday. Not perfect, but flyable.

Using the Walkera RX2702V receiver/gyro with align DS420 tail servo fwiw.

tl;dr - Carbon fiber tail blades introduced a lot of tail wag, even when just hovering. Stock, large plastic blades made the problem go away.

[eddiepierre]

Good luck if u do try the tail! I'm also running a fbl system the 3g, I was convinced that it was not that causing wag,,,, and besides I had sold my 750gyro and fb head so had little choice in getting it to work! it was just a case of trial and error,, I literally had no where else to go if the tail change failed to work!

[eddiepierre]

Microheli tail

[eddiepierre]

Trying to publish a photo from my iPhone!

[eddiepierre]

[Steve Joblin]

nice photos! Many have claimed that the tail blades need to be a bit tighter in the grips than most other (larger) helis... looks like your are a bit floppy.

[eddiepierre]

Hi ste, yeah i believe they should be a bit tighter!
like just "nipped" up tight but not over do it! gonna try it out this eve at local in door club<<<< and experiment!

post my findings later!

[shepster]

Just thought id share my wag fix - the gyro is a gy401 and servo is a ds420.
Originally i had the gyro mounted upside down on the gyro mount plate.
The plate was fitted to the upper mounting slots in the chassis.
I cured my tail wag by simply lowering the gyro mount plate to the lower slots in the chassis, with the gyro still mounted upside down. I think the gyro was interfering with the servo and causing the wag. I am running the standard tail, belt, servo rod, all standard. gy401 is at 65% gain on HH mode (DX6i TX)
Hope this helps someone!
cheers

[exit44rc]

No Chinese weights on the MH tail? That's a totally different idea than Align.

[exit44rc]

I don't see any tail shafts on the MH website. Are you just using the stock Align one? Second question, do you have to replace the entire casing or can you just replace the blade grips, hub, tail slider, and actuator arm and keep using the stock align casing?

[Rotor Ruiner]

I dont know if this has been mentioned before. I run mine with a Futaba 7C, completely stock 250 super combo, with the gp750. It wagged like crazy at first.

Mods added, counterweighted 250SE tail blade grips, KBDD tail blades. I noticed the grips had a ton of play at the tail hub. I just doubled up the tail grip bearings with no spacer between them and used a spare tail blade bolt to attach it back to the hub. It has a little play, but nowhere near what it was. Align metal tail bellcrank was then added and it has too much play where the tail slider fits in. A thin film of CA fixed that up to an acceptable level. Lastly, made sure there was no binding anywhere in the system. I had to file a few spots on the pitch slider.

Futaba gain settings with the GP750 :
Normal (rate mode) 30% at 75% throttle
Idle 1 (HH mode) 28% at 90% throttle
Idle 2 (HH mode) 28% at 90% throttle

ESC has the GOV mode enabled
Pitch is set to +10 , -10
Cyclic is set to 5 degrees
Align plastic main blades
Ball is 6mm out from the spline on the stock DS420

NO wag at all, minor tail kick (10mm max) during HARD pich changes. I can live with that. The doubled up bearings and KBDD tails make a huge difference.

[baller]

I have had tail wag haunt me sins day one on my 250. i was board tonight so i thought id try some other servos out that i had i have tried ds 3500g , 9257 and ds 420. Just tonight i tried the ds 520 off of my trex 500 and all i can say is awesome why didn't i think of this sooner. My heli is stock besides the servo. CHEARS

[Brad_M]

I had the usual minor wag to the odd episode of major wag and then replaced the GP780 with a Quark with pretty noticeable improvements but not perfect. Then the pursuit continued with the MH Tail, as others have mentioned worked for them. WOW amazing ! There is no slop in the tail and I am pretty convinced now that for me that was the root of most of the evil. I was planning on the 3500G and probably will anyways.
It fly's like it should now.

[extra3d]

...

[aarsevin]

Just throwing this out there. Despite my previous posts I was still having tail wag issues. So I moved my servo position to this new position and the wag is gone. I was looking around for pictures of proper set ups and I found one of Bert Kammerer's 250 while he was doing a review or something of the sort. I matched the servo and horn position from that picture. This is the end result, and without adding a carbon fiber tail control rod, my wag is gone. The old hot needle trick gave me the hole I needed in the servo arm measured exactly to 4.5mm.

Just for reference I also have a metal control arm and microheli grips.

My original set up had the ball link on the inside of the servo horn and I had the servo positioned on the other side of the tail servo holder. I think that was forcing me to put the ball too far from the center of the servo even though I was as close as possible without binding.

The pics below are the final set up. Log in if u can't see the pics.

[xrated]

HI all I'd thought I'd add this info for anyone who is banging their head with the dreaded 250 tail wobble/vibration problem.

I had a crash and since then I've tried every thing to cure it with no success until now.

I changed the tail unit, belt, blades, top and bottom main shaft bearings, one way bearing, grips all round all with no success.

The thing that cured it was the collar on the upper main shaft bearing was too tight and wasn't giving the one way bearing enough free play. When i spun the main blades by hand they didn't spin freely for a long time they spun a bit then kinda stopped.

After loosening the collar i pushed the main shaft down a little so that it has enough play to spin freely for a long time. I then flew it and NOTHING ! no wag ! nothing at all ! rock solid and smooth and flies like when it was new.


Its probably really obvious to the pros out there but it might help someone anyway.

Steve.

[CHIEF-X]

heres what i have on tap for my 250 beasx project.

1. beastx with dsm2 satelite
2. scorpion 2206-3900 kv motor
3. phoenix 25 esc
4. align ds410m servos
5. FULL MICROHELI PRO TAIL SETUP
6. CARBON FIBRE SERVO ROD
7. JRDS290G SERVO

will all this stuff work in harmony? did i choose the right things for a good heli? dont be afraid to comment and i would totally love any tips or advice as specially on tail setup and phoenix 25 esc.

thanks for all helifreaks... i love this site

[ahahn]

I seemed to have fixed my small wag (Quark Gyro, DS420 servo) by fixing up my bellcrank mount--I sanded the base of the plastic bellcrank so that the bushing is slightly taller than the bellcrank. I also polished the outer part of the bushing so that the bellcrank smoothly and frictionlessly (well almost!) can rotate around the bushing.

I mount the system and "crank" down tight on the mounting bolt, washer, and bushing-this makes a nice solid post now. Bellcrank rotates nice and smoothly around the bushing with no slop.

Previously the bellcrank/bushing was rotating around the bolt, but this was not a nice solid setup, because the bolt had to be loose enough to clear the bushing and tended to "wobble" a bit. Had a small wag then, but now it really is gone!

Should note that this is the stock Align 250SE tail, but with the HeimJoint two-bearing fix and Chinese Weights (see Aftermarket Products sticky for HJ products). Fix was after this setup was in place.

[faithalone]

Just gonna chime in on my experience- I never had any tail wag issues until my first crash. The stock pinion had slipped off and I replaced it with a pinion with a set screw. I then had some pretty visible tail wag and discovered that I had the pinion and main gear mesh a little too tight - loosened it up and voila