swash wobble at low speed...is this a problem?

[pscm]

On second protos build after I programmed ESC I wanted to ensure motor spool up before setting robird governer. I have no blades on it at this point. At very slow rpms I notice a bit of a wobble in the swash and at higher speeds I can feel it through the anti rotation bearings but would not call it severe. Tried new mainshaft and did not help. I would expect to see a little of this due to tolerances but wanted to inquire. Suppose I could run it and see what type of vibes I am seeing.

[crickr1]

Bring up the rpms and see if it goes away if you are sure shafts not bent. Could be a harmonic low speed issue.

[solex227]

Had this same issue.. I changed out the swash and the wobble vanished. Out of the two swash plates one is new and the other is the old style don't know which is which but it just maybe the swash plate that could be creating the low speed wobble you see....


Solex227

[pscm]

Ran it without blades and the robird doesn't indicate any high vibes. Will be interesting to see what I see with blades on. Definitely can be felt. It is an older swash.

[solex227]

The newer swash plate has flat spots for the inner short balls correct?

Solex227

[dr dremel]

Yes. Old inner swash round, updated swash with raised flat spots

[solex227]

Originally Posted by dr dremel

Yes. Old inner swash round, updated swash with raised flat spots

+1

thank you dr dremel for confirmation

pscm

I think we have the same issue then... Ill ask this one last question.. at low rpms set and Negative pitch do you see the wobble? and does it go away when you go into positive pitch? If so I will stick my neck out and say its is the swash plate.. that is the exact same issue I had .. and though the swash look perfect it wobbled .. the new one is rock steady at any pitch.

Im no expert on this but could one of you guys confirm this and Also, with the old swash plates could you take them apart? if so how?

Happy flying!
Im not going to Huntsville today But I WILL BE FLYING AT HOME!!

Solex227

[pscm]

I ordered a news wash today. I took the bladesoff my other protos and movement is nil.

[pscm]

Replaced swash tonight and problem gone. For the record I had the old style with round inner plate where the ball ends mount. New one received is flat.

[matthewcornell]

Just so I understand: Has anyone found a new one to cause vibes? Mine is shown here, BTW: how much should the bottom of the swash race protrude under?