Page 12
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Construction Manual
Step 62 - Fuselage Assembly (wing attachment bolts)
Slide the wing into the wing
saddle and push the rear hold
down pins into WH4 (lightly sand
as necessary for a good fit).
Then allow the wing to rest in
the wing saddle. The wing is
perfectly aligned when the distance
from the left wing tip to the rear of the
fuselage is the same the distance when
measured from the right wing tip.
When the wing is aligned, use a pencil to transfer the wing’s bolt
holes through to WH1/WH2 already installed in the fuselage.
Remove the wing then drill two 3/16” holes, centered on the marks
you just made. When drilling, take your time and make sure the
drill is held so the bit is held straight.
Remove the drill, and clean up around
the new holes you drilled.
Run a 1/4x20 tap through holes you
just drilled so that the wing bolts will
thread into this block. A few drops
of thin CA will help strengthen and
secure the threads you’ve cut.
But, if you prefer, you can enlarge these
holes to 5/16”, then install 1/4x20 t-nuts instead (not included).
Step 63 - Fuselage Assembly (stab alignment)
Although we’ve done everything possible to engineer the Mambo
so it will build straight and true, take a few minutes to guarantee
things are straight before gluing on the tail surfaces.
First bolt on the wing. Now, to align the stab, slide it in place.
Look at the fuselage straight on, from the nose (or tail) and make
sure that the stab is level with the wings. If not, remove the stab
and gently sand the stab cutouts in the fuselage sheeting a little at
time. Check the stab and
re-sand the supports as
needed.
Step 64 - Fuselage Assembly (stab alignment)
Once leveled, ensure that the
stab is aligned with the wing
by measuring the distance from
the left wing tip to the left tip
of the stab. Compare this to the
distance between the right wing
and right stab tip. Slide the stab a
bit until these two measurements are
equal.
Use a pencil to mark on the stab where it
intersects with the fuselage on each side, then
Remove the stab, apply glue in the fuselage slots, then attach the
stab in place.
Using scrap 3/16” square
balsa, cut two pieces, roughly
3” in long. From the underside
of the fuse, glue one of the
strips in on each side where
the fuselage and stab join -
this will stiffen up and support
the joint.
Step 65 - Fuselage Assembly (PG)
Before the top and bottom
sheeting is installed, we
recommend installing the
elevator and rudder pushrod
guides inside the fuselage.
Pushrods are not included
and we recommend a set of
flexible pushrods, similar to
those by Du-Bro, Sullivan, etc. These have an outer tube which
is permanently installed in the fuselage. We include a set of PG
pieces on BP4 to act as pushrod supports. These are meant to be
glued to a couple of the formers and the pushrod’s outer tubing
then glued to the PG pieces, similar to what’s shown in the photo.
Step 66 - Fuselage Assembly (aft bottom sheeting)
Now, using the 1/16” sheets
it’s time to sheet the bottom
of the aft fuselage.
This is done a piece at a
time, starting up against
the back of LG3. Hold the
1/16” sheeting against the
fuselage, making sure the
grain is cross-ways. Mark,
cut and glue the first 4” section of sheeting in position. Using this
same technique, work your way backward 4” at a time, until you
reach the rear of the fuselage. Be careful not to waste as little of
the sheeting as possible.
Step 67 - Fuselage Assembly (front bottom sheeting)
Now, using the 3/32” sheet
it’s time to sheet the bottom
of the front of the fuselage.
This is done a piece at a
time, starting up against the
front of LG3 and running up
to the joint in the fuselage
side sheeting (see diagram). Carefully mark, cut and glue sections
of cross-grain 3/32” sheeting.
Step 68 - Fuselage Assembly (vertical fin)
Locate the vertical fin assembly from
and glue it in place as shown. The fin
should be firmly seated in the pre-
cut grooves in both F7 and F8A.
Sand the fin if necessary to get a
firm, slop-free fit. Also ensure that
the fin is perfectly vertical (90° in
relation to the stab).
Mark and trim the 3/16” longerons as needed for clearance.
Step 69 - Fuselage Assembly (top sheeting)
Using the same techniques
used to sheet the bottom of
the fuselage, it’s now time to
sheet the top. Again, use 1/16”
sheets, cross-grained, in 4”
sections at a time.
When you reach the front of the
A
A
C
C
B
B
3/32”
sheeting
Sheeting
stops here.
