L-39 MOLDED KIT UPDATES
This is an update to the elevator torque rod set up.
We have changed to a two servo set up on the
elevators instead of a single servo single push rod
set up.

 

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1. Cut the spar stock into 2-6" pieces.  Glue the spar in the stab using slow cure epoxy leaving 3/8" of the spar sticking out as shown.

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2. Make up two torque rods from 3/32" music wire.  The torque rod is 1 1/8" long between each 90 degree bend and each bend will b e1/4" long.

 
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3. Another look at the torque rod.

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#4. Measure in 15/16" and by hand drill a 3/32" hole in the face of the elevator and insert the torque rod.  The torque rod can be glued in place using thick CA.
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5. Another look at the torque rod once installed.

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6. Mask off the torque rod leaving 1/4".  Using a large pair of wire cutters or a dremel with a cut off wheel cut the torque rod at the top of the tape line leaving 1/4".
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7. So that you can attach a metal kwik-link to the torque we used a 3/8" length of 1/8" brass tube.  Using a pair of pliers crimp one end of the brass tube and drill in the center of the crimp for a metal kwik-link.  Using Silver Solder, solder the opposite end of the brass tube to the torque as shown.

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8. Test fit the stab with torque rod and brass tube to the fuselage.  At no point can the torque rod with brass tube rub against the inside of the fuselage.  To adjust the torque rod it can be slightly bent out to avoid touching the fuselage sides.

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9.   Once you are satisfied with the fit of the stab and you have proper clearance of the torque rod the stabs can be glued in place using thick CA.  Be careful not to glue the torque rod when gluing the stabs in place.  The use of a small amount of petroleum jelly around the torque will help to prevent this from happening. 

 

 
10.  As for the servo and push rod set up we have gone over to the use of two HS55 size servo's instead of the one HS81.  Each servo will be glued to the inside of the fuselage about 10" in from the back of the fuselage.   The servo's will set right next to the rear of the fan unit. Be sure that the servo nor the servo arm hits the fan unit in any way.  We used clear automotive silicone to glue the servo's to the fuselage sides.  The push rods should be made of 3/32" music wire or graphite rod.  The use of a EZ connector works well on the servo arm and a metal kwik-link at the torque rod.