Play In Main Shaft

[diyman]

Hi,I have a Shuttle ZTS.
There is slight play in the main shaft,more at the bottom than the top.
I'm talking side to side not up and down.
The play is there(you can feel a tap,tap when moving the top part of the shaft)
Should there be play?
I'm thinking being as the shaft goes through sealed roller bearings,there should not be.
The main blades spin smoothly with no bearing noise.

Do the bearings need to be greased,if so how.
Any views,
Thanks,Brian.

[Duracizer]

I may be wrong on this, but being as the bearings are sealed you will have a hard time trying to get in at them. How old are the bearings? It sounds like they may just be shot and need to be replaced. Even if they are not greased they shouldn't have any side to side movement?

[diyman]

I agee with you about they may be shot.
I can't say how old they are as i bought the heli second hand.
I am an engineer so i would say there should be no play in the sealed bearings.But i thought i would check first.

Thanks for your reply.

[Duracizer]

Better safe than sorry, I would switch them out with new ones...

[rob_jones]

I've seen the bearings get loose in the frames on older Shuttles, but I've had my Shuttle Plus for over 3 years and the bearings are still tight (it uses the same frames as the ZTS). I doubt replacing the bearings will do much good (but it can't hurt).

What I usually do is put some blue locktite on the outside of the bearing before putting it in the frames. That will help to hold it in place. On the older shuttles, we used to epoxy the bearings into the frames to keep them from moving. Of course, you have to be careful not to get any locktite or epoxy into the bearing itself.

Be sure that bolts holding the frame halves together are tight and that the collar on the mainshaft above the upper bearing is tight. If all that checks out, try using some locktite or epoxy on the bearings. If they are still loose, you may need to replace the frames.

[diyman]

Hi,I have taken the bearings out and the clutch shaft bearings as well.
There is slight play but they do not make a noise or are clicky when spun.
I have ordered some more to replace them.
I did find a couple of the bolts on the main shaft not as tight as i had assembled it before :shock:
I'm sure i lock tighted them.
I will take your advice and Locktite the bearings in the frames to stop them turning,although i do not think that was the problem.

I have taken the engine out and changed the engine mount as the previous owner had snapped a bolt off on the mount to frame side.

I have also checked the lining in the clutch housing to find it o.k.

I did have a strange look from she who must be obeyed :bomb: .
Probably something to do with me using the kitchen as a workshop. :D

[rob_jones]

Probably something to do with me using the kitchen as a workshop.

Not wise if you want to keep her and the helicopter! :wink: Find yourself a cheap little folding card table to use instead - they are also great to take to the field if there aren't already tables there.

As for the bearings, do this:

Clean the frames with alcohol where the bearings are installed.

Put a small amount of BLUE locktite on the outside of the bearing, and install it.

Once you have all bearings in place, put the frame halves together and put the bolts in, but don't tighten them.

Put the main shaft through the two bearings to make sure they are properly aligned.

Then tighten the bolts holding the frames together.

Put BLUE locktite on the nuts for the frame screws.

Give the locktite 12 or so hours to dry before flying.

I have used this method for years on plastic framed copters and it works!

[diyman]

I cant see what see was complaining about. :lol:

http://www.helifreak.com/album_showpage.php?pic_id=3376

I will follow your advice on the assembly.(and the table as well)
Thanks for your advice.

[rob_jones]

Hmmmm, I could not imagine.... :mrgreen:

Cool. Let me know how it works out!

[diyman]

Hi,I have repaired the heli by replacing the bearings.
There wasn't that much play on the old ones but the new bearings have made a difference.
It was good to find out how the helicopter is put together.
Have left it for 12 hours for the loctite to go off and hopefully have a test hover tomorrow.Although the weather is a bit windy at the moment.
Thanks for all the inputs,Brian.

[rob_jones]

Happy to help. I hope you got it taken care of!

[diyman]

I must admit the bearings worked great on my test hover.
Untill i crashed :shock: :oops:
See "2nd Crash"in the newbies section.

[rob_jones]

D'oh! :DOH I hate when that happens!

[Duracizer]

Sorry to hear it!