Rotational play in the main rotor shaft

[OliP]

Hi guys,

not sure whether I missed something when attaching the main gear to the rotor shaft. The bolt (M2,5x16 according to the manual) isn't exactly a tight fit in the rotor shaft hole, so there's quite a bit of rotational play… almost 3cm (!) at the blade tip.

I'm worried this will put too much stress on the bolt. Any ideas?

Cheers
OliP

[Dowquest]

Well, I've got twice that. 2 1/2" at the blade tip. I haven't had an issue with it or noticed, but I think I'll pull my bolt through the drive hub and take a look at it.
As a comparison, I've got 1" on my trex500.

[whitehedr]

Once the blades are spinning and under load that play will be gone.

ROG

[OliP]

Well, I don't care too much about the play itself. I'm thinking if the bolt doesn't fit snugly (as it does in my other heli) then the contact area between bolt and shaft is greatly reduced, even under load… and the bolt will be stressed a lot where the edges of the shaft hole bite into it. Wrong?

[Dowquest]

I pulled my bolt out and inspected it, it looked fine. After reinstalling it, most of my play was gone.?? It was tight originally, but, I'm just gonna fly it and not think about it.

[Michaelinpr]

Pretty normal. Once you spoil up the bolt will not have play as the force against it will only be in one direction. I have about 3cm rotational play on the bench as well.