This evening’s task is assembly the frames for each nacelle. If you’ve built a couple of non-ARF helicopters in the past there won’t be any real surprises here, but definitely follow the instructions as the Osprey doesn’t function like a normal heli.
A note of clarification: One tends to look at the nacelles in their horizontal (cruise flight) orientation, but as the instructions note, you should look at them in the vertical (hovering) orientation, as all notations in the instructions are based on that.
The instructions show how to tell the inner left, outer left, inner right and outer right nacelle frames apart. There is one of each, so make sure you can tell which is which. Loosely assemble the left nacelle, using blue Loctite on all threaded fasteners. Leave all screws loose until you install the main shaft, and only then tighten them. In this way the main shaft can act as an alignment jig to assure all bearing blocks are perfectly aligned.
Next the ball links are installed on the control arms. These arms link the servos to the swashplates. They install nearly against the nacelle frames, so be sure and grind the ball link screws flush with their backs if necessary.
Flanged bearings are inserted into the nacelle frames for the control arm mounting rods. These should be a press fit. If they’re too loose VERY carefully CA them into place. Mine fit perfectly – snug but not too tight.
The narrow nacelles of the Osprey require a two-stage gear train for the main shafts, so the lash between the two gears has to be set before installing the motors. Take your time to get this just right.
Finally the previously-assembled swash plates, swash drivers and rotor heads are installed. If you squint a little, it’s starting to look like an Osprey!
This is pretty good progress for two relaxing evenings of work. Next up will be setting up the conversion mechanisms for transitioning the nacelles from hovering to high-speed flight.