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Cut the Servo Bays

The LightHawk servo bays go inboard on the wing, under the center doublers. This is the same configuration as used in the Super Gee II. We are working on all templates including those for the servo bay cutting, but for now, you can use the Super Gee II plan sg2_rds.pdf as a guide.

 

If you are cutting for RDS, use the sg2_rds.pdf exactly. If you are cutting for conventional pushrod and control horn, just rotate the servo bays in place, guided to the flaperon control horn at approximately ___ outboard from the root of the flaperon. For easy wiring of D60 servos, control horns go to the outsides.

 

Tools:

Materials:

Cut the outline of the servo in the wing skin

  1. Locate where your servos should go, depending upon whether you are using RDS or standard control linkages. Mark the location on the wing using the intended servo as a template. You want a tight fit around the servo body, and just enough clearance around the control horn for full range of movement.

    Conventional: For servos with wires exiting the bottom of the servo case, the easiest installation will have the control horns towards each wing tip.
     

  1. Position the servo in it's correct place, and using a air disappearing marker pen, mark the outline of the servo. Or tack the template on the wing and cut through the template. Or perforate the template and hold it in place while you draw and outline.


     

  2. Using a short up and down stroke, cut the Kevlar on the outline. Make the holes as close to the servo as possible, as you want a tight fit for the servo.




     

  3. Remove the skin piece from the foam where the servo should go. You should have an area of exposed foam the same size as the servo you are using, with an area cut out for the control horn movement.


    RDS, then Conventional

 

In the case of the standard control linkages, the servo bay should allow for the control horn to move forward and back to it's full travel without touching the foam.

In the case of the RDS control linkages, there should be enough space for the yoke of the RDS shaft to mount into the control horn and be able to rotate freely.

 

  1. Using your hobby knife, make a straight cut into the foam along the edge of the exposed area. Slice it gently down to the top skin, taking care not mar the top skin doublers.

You are now ready to remove the foam.

Remove the foam from the servo bay

The servos are mounted flush with the bottom of the wing, and are snugly fit into the foam. You need to remove just enough material for the servos to fit.

 

Alternatively, you can pick out all the foam and insert approximately .020" or .5 mm  thick flat spacers in the deeper part of the servo bay. This lifts the servo to horizontal with the bottom of the wing.

 

Either way works. :)

 

Routing Just Enough Foam

 

  1. Using a rotary tool with a router bit, carefully remove the foam from the exposed area.

    Take care to avoid routing the top skin away. Do not go deeper than your servos depth. For D-60 servos, there will be a small layer of foam remaining.


    Set the depth for your dremel router



    Remove the foam with the router



    For the RDS angled cuts where the foam thickness tapers significantly, take care and work in sections with different height settings to ensure that you do not route through the top skin!



    Vacuum away the foam pieces so you can see your work



    After routing you can see the wiring channels that are pre-bored into the wing
    Making the closest part of the servo bay about 1/2" distance from the root will ensure you uncover the wiring channel, and ensure you put the servo bay cuts in the specially reinforced areas on the wing.
     

  2. After you have routed away the foam, dry fit the servo to make sure that it is flush with the bottom of the wing and fits snugly. Make sure the control horn has enough space to move.