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Twenty
Wing Rigging: Joining the wings to the
fuselage. This is something that has to done right and, I admit, I
feel the pressure. I'm trying to be meticulous in my preparations. Wish me
luck!
 21
May 2010: Securing the lift strut brackets. I temporarily attached the
lift strut brackets to the wing spars with hose clamps. If you look
closely you can see that I wrapped them with duct tape to avoid damaging
the spars. The exact position of the brackets will be determined during
the rigging process. At that time I will permanently attach the brackets
with rivets and epoxy.
 22
May 2010: First I attached levels to the fuselage. The fuselage has to
be level both fore and aft and side to side. The levels will help me
establish this when I move the fuselage into position.
 Next
I attach "line guides" to the wing tips. In order to establish the
proper sweep a line that stands 1 inch away from the forward spars must be
stretched from wing tip to wing tip. (The word "in" indicates which side
of the block I want to face inboard.)
 Witness
Mark. Exactly 120 inches from the root of each aft spar I place a
mark. By measuring from a select point on the tail I can insure symmetry
in the way the wings fit the fuselage. Because the marks are prone to
rubbing off bare aluminum I used masking tape.
The last thing I do is gather all the hardware. Referring to my
inventory records I retrieve all the hardware and place it all in a
dedicated box.
 24
May 2010: After consultation with John McBean at Kitfox, I reposition
the level across the spar carry-through tubes. The smaller level assures
side-to-side orientation.
 Preparing
the Lift Struts: I begin by reaming the holes where the strut meets
the fuselage.
 End
Fittings: 1/4" of thread showing.
 28
May 2010: Leveling the Fuselage. I moved the Cessna to a safe place
across the airport. This makes room for the wing rigging. the first step
is to level the fuselage in the center of the hangar. Linda and I do this
together.
 Adjustable
blocks: Carriage bolts, nuts, and washers. Along with blocks of wood.
A simple way to make fine adjustments to the level of the fuselage. I've
stabilized the fuselage with shot bag style scuba weights.
  Witness
Marks: To allow spotting the exact point on the forward spar where the
hole should be drilled.
  Mounting
the Lift Struts: Using a temporary brace to prop the lift strut in
position we mount the lift struts on the wings.
 Ready
to go: Tomorrow we mount the wings to the fuselage.
 It's
Tomorrow and it's starting to look like an airplane, 29 May 2010: I
enlisted a former tuba student, Colin Autry, to help Linda and I to rig
the wings.
 Some
details: You can see the line stretched from wing tip to wing tip.
It's weighted with a 2 once fishing weight to make it align with the spar
center lines. This was to establish a zero degree sweep. You can
also see the steel strap and hose clamps used to hold the forward spar in
position. I stole this idea from Ken Birchard when I studied the photos in
his TeamKitfox album.
Permanent attachment of the Lift Strut Brackets.
  31
May 2010: Drill and Cleco! I was able to do three brackets before
running short of clecos.
  5
June 2010: Rivets and Epoxy! I was able to complete one
bracket. Surfaces have to be polished with a Scotch-Brite pad and cleaned
with solvent to ensure a good quality bond.
  7
June 2010: Another Bracket Complete!
 I
also complete the drilling. Because I have to mount the wings on the
fuselage one more time to fit the jury struts and butt ribs I'm doing this
work in the hangar. The disadvantage over working in my garage is that
much of my time is occupied driving to the airport and back. Also there is
no escape from the heat. One advantage, however, is that I can use my air
tools in the hangar. At home in my garage I would not subject my neighbors
to the sound of an air compressor.
 9
June 2010: The final two brackets are bonded and riveted in place.
Spar Reinforcements: Attaching the steel reinforcement plates that
I prefabricated last February.
 11
June 2010: It's tight! But I successfully positioned each wing to
allow access to the root end of the wing spars. (I won't tell you how many
times I hit my head on the Cessna's lift strut.)
 Clamped
into position: A carriage bolt and nuts holds the plates in alignment.
 12
June 2010: Holes are drilled first to 3/32"
Then enlarged to 1/8"
 Finally
they are glued and riveted in place.
14 June 2010: I'm ready for the second fitting of the wings. This will
have to wait until I finish my commitment to work at the
Stetson University Brass Camp. I expect to be back to work on the
Kitfox on 11 July.
  12
July 2010: I'm back to work. In a few days I will remount the wings to
the fuselage in order to fit the butt ribs and jury struts. Among other
tasks I glued aluminum strips to reinforce the area where the canopy will
eventually be mounted.
  13
July 2010: Another one of my drilling jigs. This time to drill holes
in the butt rib brackets.
  14-15
July 2010: Second wing fitting.
Linda and I remounted the wings to the fuselage in order to fit the butt
ribs and the jury struts.
  Butt
Ribs: The instructions tell me that the flanges should face outboard
but I couldn't make it work. With the flanges facing inboard they fit
beautifully. Of course this deviation from the plans could haunt me later.
I'll just have to take responsibility for it. The shims are made from
1/16th thick hobby basswood purchased at the Hardware Store.
 Clecoed
in place: Varnishing and permanent attachment has to wait until the
wings are removed.
 Jury
Struts: This photo shows the right strut clamped in place. I have to
confess that riveting the brackets to the spars was difficult and awkward.
Some of the rivets did not seat well. I decided to let the epoxy cure to
assure proper alignment and then drill out the offensive rivets and redo
them one at a time. Since the struts will not be in the way I should have
an easier time of it.
 The
end of a long day: 98 in the shade with the sun streaming in. We've
finished the fitting and put everything away. The Cessna can now return to
its place in the hangar.
 18
July 2010: I did have an easier time of it. I drilled out the bad
rivets and replaced them with good rivets.
  Bending
the butt rib tabs. I improvised a poor man's bending brake with a bar
clamp and two pieces of wood. It worked quite well. Once they were aligned
to the butt ribs I trimmed them with a Dremel tool.
 Finished:
Butt ribs riveted in place. I varnished them in position since I forego
spraying and brush it on.
Progressing from here, My Plan.
At this point I plan to bring one wing at a time back to my garage for
completion. "Completion" meaning that it is fully assembled, covered with
fabric, and ready for paint. Once both wings are back at the hangar I'll
bring the fuselage to the garage for assembly. Once the fuselage has been
covered all parts will be taken to the hangar for painting. After
painting the fuselage will be brought back to the garage for completion.
When that is done everything will be gathered at the hangar for final
assembly.
Completing the Right Wing
  19
July 2010: Back to the Garage! The right wing, its stand, and both
flaperons have been transferred to the house. You may notice a pink ribbon
on the top stringer. It's surveyors tape and its marking a place where the
glue has let go. Since it will take a very small amount of epoxy I'll wait
to fix it until I have to mix glue for a larger project.
 20-21
July 2010: The last false ribs have been glued in place. They also
have received their first coat of varnish.
22-23 July 2010: Varnish! With the exception of some places on ribs
1 and 10 all the wood now has a second coat of varnish.
 24
July 2010: Fuel Tank! Trial fitting the fuel tank.
 Relief
Cuts! I carefully made cuts in the flanges to make room for the spar
reinforcements. The danger is, of course, cutting through the tank wall. I
managed to avoid this.
 Fittings!
Sealed with thread seal and tightened just beyond hand tight. The threads
in the tank will not tolerate an aggressive amount of torque. I'm letting
the thread seal cure overnight before I flush the tank and permanently
install it. You can see places where the end rib needs additional varnish
and epoxy
 25
July 2010: Fuel Tank is Installed. I used the silicone adhesive that
was supplied with the kit.
Fabricating the Sight Gauge Plate. A picture story.
    
 Complete:
I temporarily fitted the sight gauge tube in place for the final
fitting. (I regret that I did not take a photo.) The priority was to make
sure that the tube was not in contact with the metal to prevent chafing.
To accomplish this I had to settle for a little misalignment of the two
pieces. I'm sure that when the airplane is complete it would be barely
noticeable. But I know it's there. In this photo you can see one of four
blocks that extend from the tank to the #1 rib. This is specified in the
builder's manual and is necessary to stiffen the rib against the pull of
the fabric. Since there was nothing provided in the kit to make these with
I elected to make them with 3/4" dowels. I intend to varnish them.
  31
July 2010: Installation of rib #2. Since the 2nd rib is just the bit
that is aft of the rear spar with a capstrip that extends under the tank I
came to the conclusion that the best way to install the it was to combine
it with the installation of the last section of the trailing edge. This
would insure proper alignment. When the epoxy is set I'll complete the
installation by blocking in the capstrip. Along with this I filled the
gaps between the tank and ribs with epoxy.
  1
August 2010: Blocking in the capstrip. By extending a straight edge
from rib 1 to rib 3 I was able to spot the location of the capstrip for
rib 2 at each point along its length and block it in place. I used old
drafting weights to hold everything in position while the epoxy cures.
7 August 2010: Time Out! For about two weeks I'll be occupied with
the Cessna's annual inspection.
14 August 2010: I'm Back! The Cessna is ready for inspection and
I'm back working on the kitfox.
 False
ribs along the bottom of the tank. The ribs have to be trimmed to
accommodate the tank. I placed a rib along the side of the tank and
spotted its position with a level serving as a straight edge. I drew a cut
line and made a rib that would serve as a template for the rest of the
ribs.
 No,
it's not foggy in Cape Canaveral. It's very hot. When I brought the
camera into the hot garage from the cool living room the lens fogged.
Anyway, I've tacked in the ribs with super glue.
 Finally
glued in place with epoxy fillets.
  15
August 2010: Leading Edge Extrusion. The first step is to make
alignment fixtures from the template provided with the kit. I made three.
 A
relief cut around the lift strut bracket.
  A
Temporary "Hinge." I use strips of duct tape to make a hinge that
allows me to swing the extrusion to a position that allows me to apply
epoxy to the gluing surfaces. A lot of epoxy had to be spread and I had to
work quickly due to the Florida summer heat.
  Complete!
I use duct tape to clamp the extrusion into position. One again my lens
fogs. I use Corel photo editing software to save the day.
27 - 28 August 2010: A shelf for a magnetic sensor. I've yet to
select what I intend to install on the instrument panel but I've reached
some conclusions:
- I will install a "glass panel" or Electronic Flight Information
System. There are very impressive systems available for experimental and
light sport aircraft at a reasonable price.
- The system I select will have separate attitude and magnetic
sensors. An all-in-one unit has to be mounted in the fuselage. Trying to
mount a magnetic sensor in a steel tube fuselage can be challenging. I'd
rather mount a separate magnetic sensor on a wing tip, far away from
ferrous metals.
The Dynon
SkyView system is an example of a system with an all-in-one attitude
and heading sensor. Aside from the sensor I'm very taken with the
"gee-whiz" features such as synthetic vision. But that leads to another
consideration. Is there a real advantage to having synthetic vision in a
Kitfox? (At least in the manner Linda and I intend to use our Kitfox.) For
us the answer is no. I don't know what system I will eventually install
but if I were to purchase it today it would be a Dynon D100 EFIS and D120
EMS.
  Once
again I resort to Google
SketchUp. I can experiment making it with virtual wood rather than
real wood. The idea is to have a permanently attached shelf with a
removable shelf where the sensor will be mounted. If I'm successful the
design will allow me to attach the sensor on the removable part and then
thread it through the end rib and attach it to the permanent part. I've
researched the sizes of several units and dimensioned the shelf to
accommodate any one of them.
 I
first use the adjustable wing stands to elevate the wing over the
rotisserie. This allows me unencumbered access to the wing tip.
 Cutting
out the parts. Aircraft birch plywood.
 Bonding
the guides for the removable shelf.
  Shaping
the end piece.
 Tacking
the parts with superglue.
 Fabricating
the outboard end piece. You're right! I didn't include this piece in
my original drawing. I had to get into the project before I could
conceptualize how to shape it.
  Tacked
with SuperGlue and then bonded with epoxy.
  I
trim the outboard end piece to level it with the wing root. If, in
addition, I'm careful to level the instrument panel vertically the
instrument and the sensor with be in alignment.
  Bonded
into position with epoxy. I use a shot-bag scuba weight to hold it.
Not visible on these photos is the epoxy fillet bonding the underside
longitudinal stiffener to the aluminum stringer.
Tomorrow is Cheer or Cry day. I'll attempt to attach the removable
shelf by reaching through the end rib. If I can do this then I will be
able to do the same with the wing covered.
29 August 2010: I'm cheering. I was successful in attaching the
removable shelf through the end rib. You will notice that I use zip-ties.
They're as non-magnetic as I can get. The guides hold the shelf in
alignment. Anyone is welcome to copy my design but, remember, until I fly
the airplane this design is unproven.
    
Done!
 Finishing
the day. I begin fabricating the mounting strips for the wingtip.
More on Page Four
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