trex 500esp up and down play in main grips

[jabu32]

I have about 5/16 play in the main blade grips. It was more but I added two different shims to tighten it up. If I add more it becomes very notchy. The bearings are good and everything is installed in the proper order. I also put new thrust bearings in. This is the only Heli I have that does this. Is this common or anything else too.I can think of? Thanks.

[jabu32]

They are dfc grips

[MS60]

5/16 is a lot - sure on that number? is the play along the feathering spindle shaft, or up / down?

[jabu32]

It's at the grips.the feathering shaft stays put. Moving one grip up and down doesn't move the other.

[Ron_R]

Sounds like the feathering shaft might be slightly bent. I would take it apart and roll the Feathering Shaft on a very flat surface, like a pane of glass and see if there is a slight wobble when you roll it.

[Gladius]

You can move 1 blade grip up to 5/16 of an inch without the other one moving? Something is seriously wrong. I know you said that you assembled everything correctly, but please take it apart and check again. Something is definitely either broken or missing!

[jabu32]

Originally Posted by Gladius

You can move 1 blade grip up to 5/16 of an inch without the other one moving? Something is seriously wrong. I know you said that you assembled everything correctly, but please take it apart and check again. Something is definitely either broken or missing!

I should have said 5/16 at the tip of the blades

[Gladius]

Ahh, OK, that's a lot better! So, what blades are you using? When you move the blade tips, does the grip move too? Does it happen with both blades/grips? Are the grips holding the blades all the way around the hub, or just at the tips?

[geouginator]

I was having the same issue. I pulled the head apart and noticed that with the thrust bearings placed on the feathering shaft, the shaft extended slightly past the face of the outer end of the thrust bearing so the scew would hit the shaft before tightening up on the bearing. I carefully filed down the ends of the feathering shaft a little at a time until I got it at an appropriate tightness without overcompressing the thrust bearing. I had to do this on a 500 pro and esp, not sure if it's inconsistencies in the shaft length or bearings or what.

[jabu32]

Originally Posted by geouginator

I was having the same issue. I pulled the head apart and noticed that with the thrust bearings placed on the feathering shaft, the shaft extended slightly past the face of the outer end of the thrust bearing so the scew would hit the shaft before tightening up on the bearing. I carefully filed down the ends of the feathering shaft a little at a time until I got it at an appropriate tightness without overcompressing the thrust bearing. I had to do this on a 500 pro and esp, not sure if it's inconsistencies in the shaft length or bearings or what.

This was the issue. There was a lot of movement in the thrust bearings. I ruined two shafts by taking off to much. The last shaft I filled down close enough. There is still movement but I'm worried to take any more off.

[geouginator]

Yeah, it's easy to overdo it. Seems like similar results could be accomplished with the right sized washers, either between the grips and head block or on the grip screws. Maybe others can chime in with simpler solutions. I found it helpful to keep the shaft locked into a drill chuck so I could test the tightness of the thrust bearing easily when filing the shaft down.

[Gladius]

Couldn't you add shims between the head and grips?

[jabu32]

I don't thing they make shims that thin. I hope it will be ok.

I'll try to take a video

[jabu32]

Trex 500esp main grip play (0 min 16 sec)

[TR450ZS]

Video does not show WHERE the movement originates. Is the head not loose on the main shaft at the Jesus bolt?

[Gladius]

You can buy shims as thin as .1mm from AMain Hobbies. Figure out what inner and outer diameter you need, and do a search for shims. Put the shim next to the head, so the whole grip is closer to the end of the feathering shaft. Just make sure you shim both sides the same so it stays balanced.

[jabu32]

Originally Posted by Gladius

You can buy shims as thin as .1mm from AMain Hobbies. Figure out what inner and outer diameter you need, and do a search for shims. Put the shim next to the head, so the whole grip is closer to the end of the feathering shaft. Just make sure you shim both sides the same so it stays balanced.

Cool. I'll look at those tonight