Bad oscillation in stunt mode...after rebuild

[Inverted Hokie]

It finally warmed up here to 40°F, so I went out to the field to see if my rebuild was gonna hold together with upgraded servos.

First 4 flights went great. She flew even better than when it was new. Full stunt mode, some inverted stuff, tic tocs, tumbling, etc. Feeling the rush.

5th flight I had a really bad oscillation/vibration when going into stunt mode. It was actually shaking about the horizontal axis (nose and tail oscillating up and down). Going back to F mode 0, she was smooth.

I didn't change anything either. Tried tightening the belt, but then tail wag ensued, so I went back to where it was. Tried adjusting gyro gain, but didn't help much.

Any thoughts on this?

The blade grips and dampeners are not new. Maybe a dampener is toast?
thanks.

[learnedthehardway]

Usually means something is bent in the head. (Main shaft/spindle)

Can you adjust cyclic gain in the 270's fbl? If it wasn't crashed and you only swapped out the servos it's probably a gain issue.

Are you using the same main blades as before and what all was changed on the rebuild?

Wore out dampers have always given me porpoising on FFF and a lacking pitch response but not much else. Actually like my dampers about halfway gone, collective is a little more forgiving that way...lol

[Inverted Hokie]

Originally Posted by learnedthehardway

Usually means something is bent in the head. (Main shaft/spindle)

Can you adjust cyclic gain in the 270's fbl? If it wasn't crashed and you only swapped out the servos it's probably a gain issue.

Are you using the same main blades as before and what all was changed on the rebuild?

Wore out dampers have always given me porpoising on FFF and a lacking pitch response but not much else. Actually like my dampers about halfway gone, collective is a little more forgiving that way...lol

Thanks.
Looks like that's Dial 1 on the BeastX. Manual says if it oscillates on the elevator axis, then it may be too high.
It's weird b/c I hadn't adjust anything and she seemed to be flying great.

[learnedthehardway]

Something I haven't had to mess with much. Maybe it's like tail gain so higher headspeed requires less gain.

Got wobbles on the aileron axis when I stretched my Oxy3 and had a really quick/jerky cyclic response and a little wobble on the Chase 360 when I first got it. Reducing cyclic gain from 50 to 45 fixed both but that was with a Skookum 540

Good luck, hope it cures your issue. If all you changed were the servos it should fix it with only a small adjustment

[Inverted Hokie]

Thanks again man...I'll let you know.

[Inverted Hokie]

Well shoot. Looks like my swashplate is hozed up. The whole plate moves/wiggles back and forth easily...probably not supposed to do that. It survived the crash, but I think flying today put it over the edge. I'm guessing the bearing in it was about gone (not sure what type of bearing).

Back to Amain for some more stuff. Swash plate and probably a main shaft to be safe.

[learnedthehardway]

That sucks. Same thing happened to the swash on my 300cfx and it's head never touched the ground. Only a stiff TH landing on the skids when a servo failed.

If a Microheli swash for the 300cfx will fit let me know, you can have it for $10 shipped if you want it. Bought one but never installed it since I got a Oxy3 and retired the 300 to the basement.

It's a silver one, very nicely made and increases throw compared to stock. Well as far as the 300cfx goes anyway. ..lol

[Inverted Hokie]

Originally Posted by learnedthehardway

That sucks. Same thing happened to the swash on my 300cfx and it's head never touched the ground. Only a stiff TH landing on the skids when a servo failed.

If a Microheli swash for the 300cfx will fit let me know, you can have it for $10 shipped if you want it. Bought one but never installed it since I got a Oxy3 and retired the 300 to the basement.

It's a silver one, very nicely made and increases throw compared to stock. Well as far as the 300cfx goes anyway. ..lol

Well thanks man, not sure if it will fit, but will look into it.
I think I'll change my handle to, LearnedTheHardWay2. This 270 has kicked my ass, but in a good way b/c i"ve learned so much.
Cheers.

[jrman83]

I would have thought cyclic gain issue.

Sent from my SM-N910T3 using Tapatalk

[learnedthehardway]

Originally Posted by Inverted Hokie

Well thanks man, not sure if it will fit, but will look into it.
I think I'll change my handle to, LearnedTheHardWay2. This 270 has kicked my ass, but in a good way b/c i"ve learned so much.
Cheers.

Don't feel bad, the 300cfx I got came with vibe issues and a defective AR7200BX that cooked servos left n right. Took 5 weeks of tinkering and arguing with tech support to get it all sorted out then the motor disintegrated midair about 20 flights later.

Swear that thing was cursed but I gained a ton of mechanical and electrical troubleshooting/repair experience in the process as well.

Troubleshooting issues has been a breeze ever since but after ditching Blade and going to Oxy and MSH I haven't had to troubleshoot anything in over a year

Blade helis are cheap to buy but end up costing more in the long run than a kit heli although from what I've read the 270 is a pretty good helicopter.

Plus when you're ready to step into something else all you'll need is a kit and motor since you can swap the servos, esc and fbl over from the 270 if you want.

[Inverted Hokie]

Originally Posted by learnedthehardway

Don't feel bad, the 300cfx I got came with vibe issues and a defective AR7200BX that cooked servos left n right. Took 5 weeks of tinkering and arguing with tech support to get it all sorted out then the motor disintegrated midair about 20 flights later.

Swear that thing was cursed but I gained a ton of mechanical and electrical troubleshooting/repair experience in the process as well.

Troubleshooting issues has been a breeze ever since but after ditching Blade and going to Oxy and MSH I haven't had to troubleshoot anything in over a year

Blade helis are cheap to buy but end up costing more in the long run than a kit heli although from what I've read the 270 is a pretty good helicopter.

Plus when you're ready to step into something else all you'll need is a kit and motor since you can swap the servos, esc and fbl over from the 270 if you want.

Great point about swapping the servos, esc, and fbl.
However, looks like Mrs. Clause has a 360 Trio under the tree for me, so a kit may be down the road a piece.

[Inverted Hokie]

Originally Posted by jrman83

I would have thought cyclic gain issue.

Sent from my SM-N910T3 using Tapatalk

Pretty sure it's the swash plate as it has alot of radial play in the top part. I'm assuming the bearing is shot. Also, first 4 flights rocked, so I think it was hanging on by a thread. Anyway, it's already apart now.

Thanks!

[crsorrell0653]

Originally Posted by Inverted Hokie

Pretty sure it's the swash plate as it has alot of radial play in the top part. I'm assuming the bearing is shot. Also, first 4 flights rocked, so I think it was hanging on by a thread. Anyway, it's already apart now.

Thanks!

Mine did the same after a crash, and there was a very thin cir-clip at the bottom of the swash that holds in a bearing, and had come partially out. I snapped it back in and that tightened the assembly back up from memory (my 270 is a long lost memory now).

[Inverted Hokie]

Originally Posted by crsorrell0653

Mine did the same after a crash, and there was a very thin cir-clip at the bottom of the swash that holds in a bearing, and had come partially out. I snapped it back in and that tightened the assembly back up from memory (my 270 is a long lost memory now).

Good to know, thanks crsorrell0653. I guess your little Beast never made it home from the neighbor's farm then? Bummer.

[crsorrell0653]

Originally Posted by Inverted Hokie

Good to know, thanks crsorrell0653. I guess your little Beast never made it home from the neighbor's farm then? Bummer.

Worse than that, I see they had a Silage Chopper in those paddocks the other day, so some lucky Cow will get it for a snack one day.

[Inverted Hokie]

Originally Posted by crsorrell0653

Worse than that, I see they had a Silage Chopper in those paddocks the other day, so some lucky Cow will get it for a snack one day.

Sounds like a theme for the next Transformers movie.

[Livan75]

Originally Posted by Inverted Hokie

Well shoot. Looks like my swashplate is hozed up. The whole plate moves/wiggles back and forth easily...probably not supposed to do that. It survived the crash, but I think flying today put it over the edge. I'm guessing the bearing in it was about gone (not sure what type of bearing).

Back to Amain for some more stuff. Swash plate and probably a main shaft to be safe.

If you have crashed its a 95% that both feathering and main shaft are bent...

If its hard enough to separate the swashplate, its even less likely that main shaft has made it...

[Inverted Hokie]

Originally Posted by Livan75

If you have crashed its a 95% that both feathering and main shaft are bent...

If its hard enough to separate the swashplate, its even less likely that main shaft has made it...

I did replace the spindle shaft, it was definitely bent. She flew great in full stunt mode for the first 4 flights. On 5th flight it was good until I went to full stunt mode. I noticed there was alot of radial play in the swash plate when I checked it over.

I did buy a main shaft just in case, along with the swash from AMAIN.
Ordered it Thursday morning and it's supposed to be here tomorrow. Amain rocks, I don't know how they manage to get parts out so quickly. I go to them for everything now. Free shipping now, along with $5 off. Can't beat that.

Cheers.