It has been some time since my last report on the Pietenpol project and many
of you are wondering what's happening. Do not be alarmed. We are making
steady progress on the project. I just have found precious little free time
for communicating these days. Eventually, that situation will change. But
for now I simply offer my apologies.
In January I reported to you that our right wing was complete enough to hoist
it into place to test fit it to the center section (and to take some inspiring
photos). At that time we were still working on the aileron structure. Once
the bracing was in place, the hinge locations were marked and the aileron was
cut away. What fun it was to attach the hinges and move the aileron! The
wing was done and ready for varnish.
At this point I would like to share a few thoughts on what we have learned
about varnishing using the Poly Fiber two-part epoxy varnish. Two things are
ABSOLUTELY CRITICAL to obtaining the best results. The first is following the
mixing instructions explicitly. The second is making sure that the
environmental conditions are right for proper curing.
Southern California has the reputation for having great weather almost year
round. When the sun is out and the temperature is delightful, it is easy to
ignore the humidity in the air. We found ourselves having to do things over
because we decided that "we were ready to varnish." Be honest when evaluating
the conditions. The instructions give temperature guidelines and say allow
additional induction time for high humidity conditions. I say, unless you're
on a production schedule, wait for a better day, if conditions are not right.
"Right" means warm and dry. There are always other things you can work on.
When mixing, DO NOT fudge on the induction time. Mix Part A and Part B, then
find something else to do for AT LEAST 30 minutes (45 minutes to an hour is
even better). Then, and only then, add in the proper amount of Reducer.
Again, do not fudge on the amount of reducer. The Reducer is a key element in
the proper curing of the varnish. By the way, better use a coffee can
or glass container for mixing. The varnish will eat right through a Styrofoam
or paper cup.
The instructions also say to apply two coats - a third coat is optional. We
achieved the best finish by applying a first coat, allowing a couple of days
curing time, then sanding with 150 grit sandpaper before applying a second
coat. The bare wood will soak up a lot of the first coat. The sanding is
necessary, because the first coat raises the grain in the wood.
You can consider the second coat your finish coat, if you are the type that
figures "it's all going to be covered anyway." If that is your mindset, then
adding a third coat would only add weight. Forget it.
However, if you are a craftsman and you want a silky smooth, glossy finish,
then sand that second coat almost completely off. Get a nice smooth surface
to the touch. Then carefully mix the final coat according to the
instructions, but add in a little extra reducer. The varnish will seem thin
and runny, but it will cure up hard and glossy. That's the ticket. You will
love the results.
So, now we have our right wing in a rack and working on our left wing at this
time. All of the components are there. It's just a matter of assembly. In
the meantime, Dave McPhee is working in the cockpit, locating the brake master
cylinders and getting that system finished and working.
I will let you know when we have reached another milestone. Thank you for
your continued interest.
Steve Williamson, Pres.
A lot of saw dust was created shaping the leading edge, trailing edge, and tip
bow. The results are rewarding. The contour looks great. The wing is
straight and square. All of the fittings for the lift struts and jury struts
are in place. With a little finish sanding the wing will be ready for
varnish.
We will be fabricating and attaching the aileron hinges this week. Once
the hinges are located, the aileron can be cut away from the wing. The
control horn is finished and attached. We need to fabricate one more fitting
- for the control wire pulleys.
On Saturday, January 17, the wing was finished enough to test fit it to
the fuselage center section. It was an exciting moment for all of us who were
present.