R2D2 Dome Pie Panel Hinge

This is a design for a pie panel dome hinge to suit [Michael Baddeley's V2 R2D2 dome](https://www.patreon.com/mrbaddeley/). This is my first 3D design, so I am still learning as I go.

I have included a modified pie panel with a flat spot and screw holes to attach the hinge, and modeled in details.

The current version of the design suits 9g servos such as the Turnigy TG9e or Hextronik HXT900.

Printing
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* The mounting plate is printed in two halves to avoid support material.
* The hinge arm has support designed in. Print standing up and remove the support material once done.
* The pie piece panel can be printed standing up on one of its straight edges, as long as you use a brim to help bed adhesion.
* The spring seat (x2) and pivot are used with 5.5mm springs to provide relive to the servo. You could alternatively use purchased hardware.

Assembly
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* Use 1.75mm filament to aid alignment while gluing the mounting plate together.
* Attach the arm t