rrTV-PHOTO   New HD TV
HOME   rrTV-PHOTO   GALLERIES   MY GALLERY   HELP-FAQ
myHOME PM pmRR MEMBERS 785 ONLINE 25 EVENTS SEARCH REGISTER  START HERE
 
1 page380 viewsPOST REPLY
GrandRC . CanoMod . Futaba-RC

.
.
Audacity Models Pantera 50 - Tiger 50 > Heli having a seizure!!!!
 
 
SilverBullet
Senior Heliman
Location: Bentonville, AR USA

Sorry if this is a repeat, but I tried searching and the Google Search is horrible.

Anyway.....Last time I took my Pantera out, it was nodding tail to nose up and down. I assumed it was due to a headspeed of 1650, and the fact I hadn't flown for a while. So, I upped the headspeed, and that didn't help. Next I took off the blade grips and re-lubed the dampers. While I was at it, I put my Radix 600 blades on. I took it out today, and it shakes violently in the air. Now it seems to be more of a side to side instead of nose to tail. It looks like my heli is having a seizure in the air.

I balanced the blades before installation, and tracked them. This heli only has about 6 flights on it and not a single crash or hard landing.

It does feel like my main shaft has some play in the bearings. Is it possible the main bearing blocks have gone bad after only 6 flights?? I checked all my linkages and screws and everything is tight.

Any thoughts of what I am missing? I was nervous landing it beacause of how it was shaking.
05-30-2008 01:00 AM
 
 
billm
Key Veteran
Location: Liberty Lake, WA

Did you grease the Main bearings during your build?
Did you get the thrust bearings installed on the main grips the correct way? Remember the ID of the races are different.
Did you check the run out on your motor?
Here is a silly check. Flybar centerd and both paddles in the same hole?
All the servos are happy on the CCPM?

My name is Billm. Cough, and I'm a Heli Holic
05-30-2008 02:15 AM
 
 
SilverBullet
Senior Heliman
Location: Bentonville, AR USA

Everything was built right because it flew smooth as can be for the first several flights. It has just been the last two flights that it has developed this shake. Could it be the swashplate? Everything in the head seems tight.
05-30-2008 03:22 AM
 
 
Heli_Man_Bob
Heliman
Location: Miamisburg, Ohio, US

Just a thought could it be that bearing block #2 was installed upside down. Are you seeing a lot of white dust from the gear rubbing the frame?

Post some photos both sides maybe some one will see something.

Keep us posted
05-30-2008 03:40 AM
 
 
SilverBullet
Senior Heliman
Location: Bentonville, AR USA

I triple-checked the #2 bearing block when I was building. Bearing block two is orientated in such a fashion that the bearing has to be installed from the bottom where the other blocks have the bearing installed from the top. I still have white dust from the main gear seating on the pinion. I verified again that it is installed correctly. I did notice that main gear #1 (larger) has some slight up and down play with main gear #2 (smaller). I can't see that there is any way to adjust for it.

I have not had a chance to check runout. When I first built and installed the engine, the heli flew fine. Is it possible that as I have been tuning it and breaking it in that the runout could be off? I plan on dropping the motor to check it again. I hate having to pull it since it is a pain.

Keep the ideas coming. I appreciate the help in diagnosing this.
05-30-2008 04:37 AM
 
 
SilverBullet
Senior Heliman
Location: Bentonville, AR USA

Is it possible that my blade grips are too tight? I tightened them slightly more than I have with the woodies. How much pressure should it take to move them in the grips?

I measured the flybar and it is spot on...actually better than my Raptor and the Raptor flies smooth.
05-31-2008 03:06 AM
 
 
Machinehead01
Senior Heliman
Location: USA

ran into this before...

I had a similar problem when the blade grip bolt started to come out of the spindle. Problem cured when I lock tited it and retightened.

Thomas

I didn't say it was your fault, I said I was going to blame you!
05-31-2008 05:11 PM
 
 
SilverBullet
Senior Heliman
Location: Bentonville, AR USA

Follow up:

I lubed the dampers, and that didn't seem to make a difference. So, I loosened the blade grips, and I put a drop of Tri-Flow on the swash. I took her out and hovered her in the drive way and she was smooth as silk. I think I had the blade grips too tight on the blades.
06-11-2008 03:59 AM
 
 
1 page380 viewsPOST REPLY
A Main Hobbies . Boca Bearings . Modefo's RC Helicopters

.
.
Audacity Models Pantera 50 - Tiger 50 > Heli having a seizure!!!!
 PRINT TOPIC Advertisers 

Subscribe to This Topic

Friday, January 9 - 12:24 am - Copyright © 2000 - 2009 runryder.com | email | link to rr | runryder needs cookie