Here
is where the fun begins for the rear spar of the right wing! You
may have noticed the agonizingly slow pace of construction...at
this rate I'll be done by 2010 (well, maybe!) Its hard to find time
for the shop nowadays, so bear with me. Anyway the rear isn't that
hard to build. Here is the outboard edge of the spar with the doubler
plate cleco-clamped into place for drilling. Later on the aileron
hinge brackets will attach here so this doubler plate adds some
strength.
The
spar is pre-punched and the doubler is not. So all you do is flip
the assembly over and back-drill through the pre-punched holes into
the doubler and you now have a matched pair for riveting. Here it
is cleco'd together.
Here
is another shot of the outboard doubler plate. Notice that I have
countersunk the outboard holes (right hand of photo). The reason is
that later on the aileron bracket will sit over this doubler here
and so basically this doubler is attached with these holes to the
rear spar with flush rivets so that when I put the aileron bracket
on it can sit flush. Its kinda hard to visualize but I think you get
the idea.
Here
is approximately the mid-point of the rear spar. This doubler plate
accepts some brackets for the flaps and ailerons, which is why it
is needed. You do the same job as before...cleco the doubler on and
match drill the holes using the pre-punched holes in the spar.
Now
this was kinda fun! You take that doubler that you just drilled and
begin to cut out a large oblong hole nar the top. This is to make
room for the aileron pushrod that will (one day!) come though here
and push the aileron up and down. I began by tracing the outline of
the hole using the pre-cutout hole in the spar (easy!). Next, I drilled
several holes near the edge as shown above to cut out most of the
material.
After
that it is just a matter of using a die grinder, sandpaper, and a
dremel to finish the cutout. Notice the nice fit with the pre-cutout
hole that came in the spar. Cool!
Ok,
now moving a bit more inboard here is a pic of a much thicker doubler
plate that goes on the inboard section of the spar, right where the
rear spar of the right wing will one day attach to the fuselage. This
piece originally came larger (look at the dwg), and I cut it down
to the proper size and polished it. This is where my bandsaw has come
in extremely handy! I definitely recommend one....it only cost $70
or so and it saves mucho time.
Here
is a shot of the inboard section of the spar. Its kind of hard to
see, but there are 2 doublers here. One very long one (about 2 foot,
"V" shaped), and on top of that is the shorter one you saw
earler. Here they are cleco'd in place for match drilling with the
underlying spar.
And
her is a much better picture of the inboard section. Notice that I
have also (per the directions) dimpled the uppermost holes in the
spar flange because this would be very difficult to do after this
assy is riveted together.
Now
the real fun begins. I primed the components and I'm ready to rivet
them together. The only catch is that many of these
holes shouldn't be riveted right now because they need to be riveted
in assembly with other things like ribs, hinge brackets, etc. So I
put tape over the holes that so not get a rivet just
yet.
And
here it is riveted on!
Next
up is the center doubler plate all cleco'd on with tape over the holes
that don't get riveted. You might be wondering what would happen if
you accidently riveted one of these holes? Well you'd need to break
out your trusty drill and drill out the rivets!
Rivets
in place!
And
here is the inboard section. Notice that I have a cleco in every hole
that should get a rivet. This is a tip I picked up from the Ordnorf
videos (highly recommended). This way you should remove a cleco for
every rivet you set. Pretty hard to screw up if you do this.
And
here is the inboard section. The rear spar assembly is riveted together!
Next up is preparing the wing ribs and match-drilling the skins on!