Any Helpful Corona Owners:

I was assembling my new Corona. Everything was going great until assembling the swashplate. Screwed down the outer race. Really didn't have a good idea of how far to screw it down. Thought my holes were lined up, and then AAUUGGHH!!! broke off the bolt/ball in the hole!

Can anyone help me not break my replacement (ordered today)?

How far down do you screw the outer race?
How do you check that the swashplate spins freely enough?
How do you line up the holes?

Thanks! I'm excited by my new heli but frustrated at my blunder!

- Nicholas

Hi, Nicholas:

I think the only help you need, at this point, is to SLOW DOWN ... "haste makes waste".

I just reviewed that section in the manual, and there really is nothing about the swashplate assembly that is articularly "tricky" or poorly exlplained.

The only thing I did differently from the manual is to put the grease in the inner race ring BEFORE inserting the bearing balls, which prevented them from falling out inadvertently. I then added more grease to fill the spaces between the balls before screwing the outer(upper) race on.

I'm quite sure you didn't have the inner & outer race holes lined up as the manual warns you about. Use another allen wrench or a piece of wire that fits into the holes to be sure they are lined up before screwing the ball screws in.

Above all, TAKE YOUR TIME, read the instructions in the manual more than once, and completely, at every step of the project. "An ounce of prevention is worth a pound of cure".

Happy Building,

Russ

Miniboy is right on the money. Grease on the bearing races will help keep the balls from running away from you during assembly. It does indeed sound like you did not have the holes lined up…

For your questions:

(These first two both assume you are holding the inner swashplate race stationary with a paperclip from underneath as instructed by the excellent manual, which describes everything below very well)

-When you screw the outer race of the swashplate on, keep turning it gently by fingertips until it contacts the balls and stops. Do not try to tighten this down. You can back it off and recheck your feel several times if you want. Remember, just until it stops. I tighten mayonnaise jars down much much tighter.

-Lining up the holes happens before checking how free the swashplate spins, so I will address that first. You should be able to look through any of the 3 bolt holes in the outer race and see the corresponding bolt holes in the inner race. If you see no holes, unscrew the outer swashplate until you can see the holes line up. This will at most take 1/8th of a turn. When the inner and outer holes are lined up, put a ball on a screw and thread it in BY HAND. Again, these threads are so well machined, it should just twist right in. If you encounter any resistance or the screw stops half way, the holes are not lined up. When the inner and outer holes are lined up properly, the bolt and ball will screw all the way in until the ball is held between the bolt head and the outer swashplate race.

(Now take the paperclip out of the hole in the bottom of the swashplate)

-Once you have one bolt/ball screwed all the way in, turn the two halves of the swashplate back and forth by hand. The bearings will not freewheel due to all of the grease, but there should be no gritty feeling or any binding. Also there should be no vertical play between the two halves. Quite honestly I have done this perhaps 8 times on several swashplates and each time the very first (tightest) set of inner and outer swashplate holes to line up provided very smooth swashplate rotation.


After you get to this point, keep following the excellent instruction manual. Put thread lock on the threads of two more bolt/ball combos and screw them into the other holes (which will obviously be lined up by default at this point). I can not give you an exact torque for these bolts as I do not have a torque meter that small. I would say about 100% of what I give it using the short end of the wrench without making my tumb bleed. I actually use the long end of the wrench, but could snap the screw off at 100% of that making a description for you more difficult. Don’t forget to back out that first bolt/ball and reinstall it with threadlock.

Let us know how things go for you.

For what it is worth,
Spiro

Dont forget it is possible to over tighten the inner and outter races and that will usually cause the holes not to line up. i had to back mine off a little to get the holes lined up. There isnt much more I can add to what Miniboy and Spiro has said. Seems they got it covered.

Thanks for the replies! Great hints/tips.

For reference, how close does the outer race get to the top of the race ring "notch" when assembled?

Thanks,

Nicholas