Empennage fairings [32.0 hours]

It’s time to dig out the empennage and start some preparation for attaching it to the fuselage. I have to take the tail feathers off, but before doing that it’s best to deal with the empennage fairings – can’t put off fibreglass work any longer. As supplied the fairings require some trimming, and in general fit reasonably well but far from perfect. Here’s what I did to each part:

The elevator fairings – I didn’t like the uneven gap around them, and the front side had a gap in the centre of about 2mm. I used good quality 3M electrical tape as a release agent, scuffed the sides and front of the fairing, and applied a mixture of West Systems epoxy and micro-balloons around the exterior with the fairing cleco’d in place. Once this set, I sanded off the excess micro down to the tape, removed the fairing and then removed the tape. I had to repeat this operation in a few sections. I also epoxy’d a narrow strip of 0.025″ Alclad around the interior along each rivet line. I decided to use nutplates to attached the elevator fairings, so they can be detached if I need to adjust the elevator counterweights, so I used #6 nutplates held in place with NAS1097 rivets. I dimpled the elevators with #6 die, and used countersink #6 screws to complete the assembly.

For the bottom rudder fairing, I used the same method. I also added a metal backplate into which I can screw the tail-light.

For the top rudder fairing, I added the interior Alclad strip as well, even though I riveted it to the rudder. I didn’t like the idea of the rivets cracking the fibreglass as they were set. The front side of the top rudder fairing had a significant gap, which I built up with a layer of glass and flox, and finished with micro. I continued a thin micro application right across the front surface of the rudder balance arm, since this is a permanent attachment.

For the horizontal stabilizer fairings – I trimmed them, and using a balsa-wood insert covered in packing tape, applied a layer of glass and then two internal layups. After trimming I used some micro to build the edges back up a bit for the nominal 1/8″ clearance, with a concave inner surface that the elevator counterbalance arms can swing across.

The empennage fairing – I covered the tailcone, HS and VS surfaces with packing tape, layered flox along the surfaces where the fairing rests on metal, and cleco’d the fairing in place. I did this in two parts – the horizontal sections first, then after release and cleanup, the vertical stabilizer. The flox released OK, and to clean the packing tape residue off the metal surfaces I used Eucalyptus oil followed by Acetone. I then trimmed the fairing down to the trim lines, first with a Permagrit dremel cutting wheel, and finishing off with a sanding disk in the die grinder. I also trimmed and sanded any excess flox that had run down across the interior of the fairing. The end result was a fairing which fitted tightly against all surfaces. I’m going to fill some of the screw holes, with the fairing properly fitted like this it is not necessary to have as many screws along each edge.

Now I have a lot of pinholes to fill. I plan to do these with the epoxy / squeegee method, then will apply a coat of epoxy primer followed by a fill primer to complete the surface work. Overall the fairings have been quite a bit of work, spread out over several weeks. Weather is cold at present, and even using the “fast” hardener I’ve sometimes had to leave a heater on in the workshop overnight to get proper curing of the epoxy.

  • fair1
    Using electrical tape as a release agent
  • fair2
    Large gap on front of elevator fairing
  • fair3
    Slathered on micro
  • fair4
    Same treatment for bottom rudder fairing
  • fair5
    Same treatment for top rudder fairing
  • fair6
    Large gap on front of top rudder fairing
  • fair7
    Fitting metal support for rudder tail light
  • fair8
    Right elevator fairing after sanding, left ready
  • fair9
    Elevators, rudder micro curing
  • fair10
    Bottom rudder fairing with micro curing
  • fair11
    Glue-ing in 0.025" Alclad support strips
  • fair12
    Flox and packing tape under empennage fairing
  • fair13
    Flox and packing tape under empennage fairing
  • fair14
    Gap between empennage fairing and Vertical Stab
  • fair15
    Flox on horizontal surfaces after release
  • fair16
    Flox and packing tape on Vertical Stab
  • fair17
    Trimming empennage fairing
  • fair18
    Fitting front Horizontal Stab fairings
  • fair19
    Fitting front Horizontal Stab fairings
  • fair20
    After layups, fill and sand front Horizontal Stab fairing
  • fair21
    After layups, fill and sand front Horizontal Stab fairing
  • fair22
    Nutplates and 0.025" Alclad strips on bottom rudder fairing
  • fair23
    Nutplates and 0.025" Alclad strips on bottom rudder fairing
  • fair24
    Dimpled #6 bottom of rudder, aft most holes not done yet
  • fair25
    Checking top rudder alignment
  • fair26
    Checking clearances with bottom rudder fairing in place
  • fair27
    Top front of rudder, with plenty of pinholes to fill


Forced break from building, and new toys [4.0 hours]

Due to other commitments, I’ve had to take a few months off from building, from April through June, but as of July I’m back at it again. Apart from doing the MPC course there was one notable event during this time, with the arrival of the finish kit, propeller and spinner from Van’s, the cowling from Showplanes, and the engine from Barrett Precision Engines. Finish kit inventory didn’t take long. Now I’ve really got to get on with it…

  • freight1
  • freight2
  • freight3
  • freight4
  • freight5
    Propeller crate
  • freight6
    Extra Alclad with finish kit
  • barrett1
    Barrett IO-540
  • barrett2
    Barrett IO-540
  • barrett3
    Barrett IO-540
  • prop1
    Propeller in crate
  • prop2
    Propeller blade
  • spinner1
    Hartzell spinner