Raptor 30/50 v1 assembly manual
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The main shaft only correctly goes one way, but it is possible to install it upside down. I had to fix one like this that was brought to me to be checked out. Look at both ends, you will see a bolt hole through the side. The end that has the bolt hole closer to it will be the bottom. Start with inserting the main shaft (7) down through the top bearing of the frameset, through the elevator control arm, and through the bottom bearing. Slide the main gear assembly (10) into place under the bottom bearing (grey gear on top). Lower the main shaft (7) down through the center of the main gear until it is flush with the bottom of the auto hub. Rotate the gear and shaft so that the bolt hole of the auto hub aligns with the bolt hole of the main shaft. Insert the socket head screw (1) and secure with the lock nut (2). Do not overtighten as that will warp the auto hub and cause it not to work. Get the bolt just tight enough so that if you don't hold the nut, it will turn with a little resistance. Next, slide on the mainshaft lock ring (3) all the way down the main shaft and against the top bearing. Put some blue loctite on two set screws (3) and while pulling up on the main shaft and pushing down on the lock ring, tighten the set screws in the lock ring. You should not have any up/down play in the main shaft.
Then slide on the swash plate (9) on the main shaft. The inside ring of the swashplate needs to be on top. Attach the A-arms (aka elevator control linkages) to the outside ring linkage balls. Next make two links for aileron control. Make then each 55mm long and connect them from the swash plate to the aileron lever on each side.
Next slide on the washout assembly (remember shouldered side down) and attach the washout linkage to the inner linkage balls of the swash plate.

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