Spinning rotor tends to "flatten" swashplate
08-16-2004, 05:37 PM
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Spinning rotor tends to "flatten" swashplate
I'm building a Raptor 50v2...
When building, I noticed that when I deflect the elevator, aileron, etc linkages and spin the rotor head by hand (and let go of the servo linkage), it pushes the linkages against the servo and wants to flatten the swashplate back to neutral. Is this normal? Won't the constant pushing tear up the servo? I havn't flown the heli, just something I noticed when building.
When building, I noticed that when I deflect the elevator, aileron, etc linkages and spin the rotor head by hand (and let go of the servo linkage), it pushes the linkages against the servo and wants to flatten the swashplate back to neutral. Is this normal? Won't the constant pushing tear up the servo? I havn't flown the heli, just something I noticed when building.
08-16-2004, 09:34 PM
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RE: Spinning rotor tends to "flatten" swashplate
If you spin the head and the links push the servos there is something too tight! Every part on that head that is supposed to move is mounted on bearings and that is what they should feel like when you rotate them. The blade holders should be virtually drag free when rotated with the linkage off. The flybar the same deal. It shouldn't take any more effort to turn these parts than it would to turn the bearings alone. If your ball links are still tight they can cause this as well. On all my helis, I can easily spin the linkage rods back and forth when it is mounted on the balls but there is no slop lengthwise. If you can't spin the rods easily by rolling the rod between your fingers, they are too tight. Everything on the head needs to be free otherwise anything that is stiff will transmit that stiffness back to your servos and they may fail causing at least a crash maybe even injury. The mechanics of a heli cannot be taken lightly. Things that are less than ideal you might get away with on a plane or rc car won't work on a heli. It will come back and bite you.
Matt
An experienced heli flyer is your best beet to check your heli out before flight!
Matt
An experienced heli flyer is your best beet to check your heli out before flight!
08-17-2004, 06:54 AM
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RE: Spinning rotor tends to "flatten" swashplate
So, on your heli, if you were to disconnect the linkage from the servo, deflect it by hand(to near maximum) and spin the blades by hand, it doesn't "push" the linkage back at all? My linkages are still pretty tight (especialy elevator) even after fixing some construction errors (ball clips on backwards, too short linkages).
So, do you suggest I get a "sizing tool" and free up the ball links then? Is this JR "link sizing tool" what you mean? http://www6.mailordercentral.com/hel...item=1&mitem=1
BTW Thanks for all the good info
So, do you suggest I get a "sizing tool" and free up the ball links then? Is this JR "link sizing tool" what you mean? http://www6.mailordercentral.com/hel...item=1&mitem=1
BTW Thanks for all the good info
08-22-2004, 05:23 PM
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RE: Spinning rotor tends to "flatten" swashplate
I narrowed down the problem. It wasn't due to tight linkages. The washout assembly is causing the "problem". I disconnected everything except the washout assembly (and I disconnected the flybar control rod to make sure it was ONLY the washout). The washout assembly doesn't allow the rotor to spin freely when tilted, it tends to push the swashplate back to the neutral position. Can someone take a peek at this pic to check if there is a problem with how I installed it? When I disconnect the washout and keep everything else connected, the rotor spins freely even when the swashplate is tilted to its extremes.
P.S. I know some of the links aren't connected in the pic, I was in the process of narowwing down the problem when I snapped the pic, but the washout arms are "as is", and how I installed them.
P.S. I know some of the links aren't connected in the pic, I was in the process of narowwing down the problem when I snapped the pic, but the washout arms are "as is", and how I installed them.
08-22-2004, 06:12 PM
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RE: Spinning rotor tends to "flatten" swashplate
Ah! Thanks! I'm glad I didn't try to fly it like that. I LOVE RCU!!! 
I notice you mounted your gyro behind the rotor, I mounted mine up front with the other electronics. Would that throw the CG off any? Wouldn't that expose the Gyro to the "elements" more? I have the GY401 as well, FYI
I notice you mounted your gyro behind the rotor, I mounted mine up front with the other electronics. Would that throw the CG off any? Wouldn't that expose the Gyro to the "elements" more? I have the GY401 as well, FYI
08-22-2004, 06:36 PM
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RE: Spinning rotor tends to "flatten" swashplate
I switched it around, and its ultra smooth now. I feel SOOO much better. Thanks again!![8D]
08-22-2004, 07:09 PM
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RE: Spinning rotor tends to "flatten" swashplate
I doubt the weight of the gyro would make much difference. Helis aren't nearly as sensitive as airplanes when it comes to CG. It makes a difference when you get into the advanced stuff, mostly inverted. I haven't done a lot of inverted yet but my gyro is as clean and oil free as the day I put it on there. That's about a year and a half!
Matt
Matt
