December 2009 - Vertical Fin and Tail Rotor.

Good progress this month.

Replaced a round head rivet on the tail boom skin with a steel countersunk one, to allow the forward bracket on the vertical fin to sit flat.

I used a 10-32 (3/16") floating nutplate for the rear fin

mount. All the spacers between the fin and the bracket/tail

boom were meticulously shaped by hand to ensure they sat flat on all surfaces, and the bolts sat square. This also mean the washers on the outer surface of the fin needed to be shaped to ensure the bolt heads sat

square (others have found that in service, the bolts shear at the head

or the front bracket cracks if very careful attention isn't paid. Here's

the rear spacer - shaped to fit the tail boom.

After cutting out the tail rotor pitch actuator arms,

I drilled them together to ensure the spacer bolts sat

square.

The tail rotor pitch actuator arms installed on the

bearing slider plates - looks nice back there now.

Then I could move on to assembling the tail rotor blades. Nice to see the shiny aluminium when they came out of the box for the first time sinced I'd bought them five years back. The end caps were shaped to fit then drilled and countersunk. Because the drawing and construction manual doesn't state what rivets are required, Kevin Lunn (the Australian RotorWay agent confirmed that 3/32" countersunk aluminium rivets were used, despite the manual's instructions to use steel rivets in the tail rotor area because of the vibration. Kevin also warned not to use a micro-stop tool for countersinking the rivet holes on the rounded surface of the tail rotor - the tool digs in and you end up with the hole too deep. Do it by hand with a drill bit - slow, but much safer.