These were designed for the RV series of planes but work well for this process.
The next area of concern is the exit point for the rudder cables back in the tail area. The rudder cables must transition from the inside of the fuselage to the outside to attach to the rudder horn.
Russ Erb (Bearhawk CD)
came up with an excellent idea for a very clean way to make this transition.
It involves buying 2 sets of rudder cable fairings as shown below from
Avery Tools:
These were designed for the RV series of planes but work well for this
process.
As previously shown, the location for the exit
point of the rudder cables was carefully measured and recorded before the
covering process began. That location was now marked on the fuselage
sides along with the angle of the rudder cables.
A canoe shaped hole was cut in the fabric as shown below to accept the rudder
fairings. The cable was then pulled out of the hole and tied off back
at the rudder stops to approximate where the rudder cable will be attached
to the rudder horn. This sets the correct cable angle.
Now the aft half of the rudder cable fairing is glued in place as shown here,
aligning it with the cable:
Then the forward half was glued on as shown here:
As you can see, the cable runs perfectly through the middle or the hole.
The rudder fairings were then covered like the inspection holes with a 1"
overlap of fabric:
Now with all of the inspection covers in place and all reinforcing tapes installed, its time to take paint gun in hand and start some spraying.
The Poly Fiber manual calls for some more Poly brush to be sprayed on to
help fill the weave and create a good base for the Poly Spray. Before spraying
on the Poly Brush, it's a good idea to go over all of the pinked edges of
the tapes with a 240 degree iron. It just helps the edges lay down
nicely and helps prevent lifting of the edges later. This was done
with small iron:
Don't skip this step. You can really feel the difference after going over
the edges with the iron. Everything really smoothes down nicely.
With everything ready, the entire fuselage was wiped down with the Poly Fiber
paint prep solvent, allowed to dry 30 minutes and then tack cloth to remove
any lint or dust. It was then sprayed with Poly Brush as per the Poly
Fiber manual. Here is the author Eric Newton busy spraying:
Note that I am keeping at an angle so I can see the glare from the light
and can tell if its going on wet enough.
After a mist coat it was allowed to cure for 15 minutes then a good solid cross coat as per the Poly Fiber manual. (note: A cross coat is actually two coats, one side-to-side and one up and down)
The Poly brush was allowed to cure for about 1 hour while we went over all of the tapes to make sure none had lifted on the edges. A few did very minor, but they were easily ironed back down using a piece of teflon sheet between the iron and the fabric.
Next it was time for the Poly Spray. This is when you get to see any flaws. The Poly Spray is applied as a single wet cross coat and then let dry overnight then another wet cross coat before sanding.
Here it is with the first cross-coat of Poly Spray:
Well, its really starting to look like an airplane now. We had just
a few, very minor tape edge lifts which will be ironed down with teflon tape
and iron before applying the next cross coat of Poly Spray. I'm letting
each cross coat of Poly Spray dry overnight before applying the next. Once
2 cross coats (that's actually 4 coats) are on, it will be carefully sanded
and then a final cross coat of Poly spray will go on before applying the
white Poly Tone paint.
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