Fitting the Landing Gear
You do the fitting and
drilling of the landing gear before
you finish installing the bottom skins.
This makes it a lot easier to get to all the
nuts. After the
skins are installed, it is
difficult to get to the ¼ inch bolts that hold the U-806-1 and U-805-1
plates. You can
still get to them, it is
made sure the 7/16 bolt in each
gear leg was tight enough
to hold the leg steady and in position, but still loose enough that I
move the leg with a little effort.
I taped a plumb line as
close to the
fuselage as I could get
it on both legs for the inside line (A).
taped the outside line to the outboard leading edge corner of the
right next to the axle bolt holes (B).
wanted to get these two lines as far outboard as possible to minimize
error. If they are
closer to the
centerline of the fuselage, a 1/8” error when aligning the four plumb
equates to a bigger alignment error than the same 1/8” measurement
It is also important to
make sure the
two outboard lines are
at the same place on the legs. You
be able to compare the two measurements of both legs to each other or
to the F-812 bulkhead if they
I then took two car jacks
and tied a
line between them, and
used that to align the four plumb lines. I put the
jacks just outboard
of the outer lines (B), and moved them until the horizontal line just
the front of the inboard lines (A).
I measured the distance from the outer lines (B) to the horizontal
here is was a matter of making a small
correction to a leg, then moving the jacks until the
inner lines (A) both
just touched the horizontal line and the measurements from the outer
to the horizontal line matched.
After I had the two gear
up, I measured from the
outside plumb lines (B) to the F-812 bulkhead.
I tried measuring from plumb line to the
moving too much. So
I made a mark on the
floor at the F-812 plumb line. Then
used a tape measure to measure to the outer two lines on the gear legs. I divided the total
difference in the two
measurements in half. I
moved the leg
that was farther forward aft by half the measurement, and moved the aft
forward by half the measurement.
I then started the entire
over, aligning the legs to the horizontal line, then re-measuring to
the mark on the floor.
Don’t let the fuselage
move while you
do this, or your F-812
mark on the floor will no longer be accurate.
all the holes are drilled, and
all the parts deburred
and primed, I would permanently install the U-805-1 and U-806-1 wear
with the four AN4-7 bolts before you rivet on the F-850 and F-851 skins. The plans don’t mention it
until after you
are finished riveting the forward bottom skins, and are ready to
install the landing gear. I
waited until then,
and could barely get a wrench to the nuts for the U-805-1s.
Start by putting
temporary bolts back
into the 3/8, 5/16,
and 7/16 holes to align the U-805-1 and U-806-1 wear plates with the
the WD-813s and WD-822s. Bolt
plates with the AN4 bolts. Remove
temporary 3/8, 5/16 and 7/16 bolts.
that you have finished the bottom ¾ of the
fuselage, “the canoe” as my wife called it, you are ready to install
from Fitting Landing Gear
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