Blade Tracking Issues

Can't imagine I'm the only one who's seen this but here goes-

Got a Nexus 30. Been flying for about 7 years. On occasion the blades "untrack" themselves. No matter how many times I adjust them during the flight (land first, stop blades...) they always re-adjust. Then if I replace the pitch rods and connectors all together the problem goes away- but here's the funny part- I rotate about 3 sets of these. Never had to replace one- just rotated the "self-adjusting" set out for a while and things are fine.

Any ideas?

[rotorz]

Hi dude
What blades do you use:?

The current set are HeliMax 30 Sport Rotor Blade White 530mm. They are pretty well balanced, I do this by hand before they get put on.

[rotorz]

I had some thoughts if all three sets of bldeswere the same make, but glass blades I can't ever remember having tracking issues with. when you lose tracking is it a large amount, and or the same direction or side of the head that is effected. How often does this happen, are questions that need answers.
It is not a phenomina that I have experienced personally other than an old Shuttle that would not stay in track for a flight or two. I upgraded the washout mixers and replaced the swashplate and it stopped. I will be looking forward to seeing the result when you find the cure.
Happy Landings

I'm not actually swapping out the blades, but the pitch rods. I've got two swash plates/assym's that get swapped around as the main rotor shaft gets bent on crashes...

I've essentially been through three complete nexus helicopters in 7 years and any good parts are rotated...

It seems that swapping the pitch rod cures it for about 2 hours of flight. If I find the cause I'll post it. Probably a vibration issue, but at this point is just a maintenance chore to check every 2 hours or so (15-17 minutes per flight).

[colin]

This may sound stupid, but could the pitch rod holes get enlarged by the stress and the cause the tracking problem?

And after you remove it from storage, and leave it lying around, the elasticity of the nylon plastic just shrinks back again to its usual tightness?

I've thought about that but I still break nails getting them on and off even when they're mis-tracking. I really need to get one of those tools to pop them on and off.

[rotorz]

What about trying different makes of ball links, it could even be the ball getting tight, this happened quite a bit on my moskito until I cut the plastic ball off and replaced it with a brass one, bet you have already been there. It woould be unlikely to be a vibration problem as it just should not vibrate, until it goes out of track of course. You did not answer how much out of track it does go.
Happy landings