Golden Era Model Service

High Quality Plan Sets and Laser Cut Partial Kits for Radio Control Aircraft

Page 11

Carl Goldberg's 1938 Comet Clipper




With the trailg edge shaped, the wing was stood up on the traing edge between 3 carprnter's squares and the 1/16 balsa shear webbing was installed on the front of the main spars.  Then the leading edge was sanded to contour.






1/16 balsa sheet is being installed between the three center section ribs.  Only a little sanding was necessary on the joint to the center rib, and it was glued in place with thin CA.  Pins were stuck through from the bottom on the inside edge of the second rib and the sheet was sawed off on the outside of the pins from the top side.  All the sections were installed in a similar maner, front to back on the top.   Once all was installed, the joins were glued again with thick CA on the bottom.  No sheeting is installed on the bottom of the wing.



The ply joiner plates are installed at the center section.  Epoxy used here.  Be sure to get the doublers centered well as the #2 ribs rest against the #1 and #3 spar doublers.



Elevator Assembly



The root of the elevators were drilled for a 3/16  (5mm) carbon fiber tube.  The bore should be centered on a round radius shaped on the leading edge of the elevator, closer to the back of the spar than the front.



The parts of the elevator join before assembly.  The brass tubing is 3/16 ID, 7/32 OD.  The sheet for the bellcrank is .032.



Use silver bearing solder to assemble the elevator control horn.  It is available in 2 or 4%, either will be strong enough but the more silver the higher the strength.   Drill the holes for the clevis  connector before assembling the elevators. 




                         The joined elevator in clamped in the proper position.  Keep the bellcrank as close to the edge of the lower sheeting as you can.  Put some balsa spacers between the tubing hinge sleeves and the stabilizer spar so the elevator spar in 1/32 or more back from the stabilizer rear spar.  Note the balsa spacers establishing the distance. Sand the spacers to the proper thickness and glue them in, using thick CA, surronding the brass tubing with the CA but do not allow glue to contact the carbon fiber joiner.  At this point the carbon fiber tube is not yet glued to the balsa elevator spars.  Next, using thin CA glue the elevator bellcrank to the carbon fiber tube.  Drill a hole through the belllcrank tube and cabon fiber joiner and put a pin in to keep the bellcrank secure from rotation relative to the carbon fiber tube.  Rotate the bellcrank so  it is 90 degrees from the elevator for aft centerline, set the end cleances at the tip and root of the elevators, and then securely glue the carbon fiber tube to the balsa elevator spars.



                            Cut off T-pins were used for the tip hinges.    There is enough flexibility in the elevator to pull the tip above the stabilizer.  Center the pin on the shaped leading edge radius and press it in about 1/2 inch, then remove it.  Put  the elevator in proper position and  insert the pin, with the free end of the pin extending about 3/16 inch past the outside edge of the  stabilizer rib.  Make a piece of lite-ply that will fit on the outside edge of the rib, drilled for the pin.  Slide it around until the  elevator is in position and glue it in place.  Glue a piece of 1/16 balsa  against the end of the pin to retain it.  See the next photo for a view of the completed outer elevator hinge.