Manzano Laser Works deHavilland DHC-1 Chipmunk, Assembly Manual

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The fuselage is covered with 1/16" balsa sheet. Patterns have
been provided on the plan to help cut each sheet section to the
proper size and shape. Making up paper patterns before cutting
any balsa is a good idea to help make sure the pieces will fit the
target section properly.
After the fuselage sheeting has been installed, the filler block
behind the wing saddle is glued in place. It is shaped when the
fuselage sheeting is sanded. The edge of the filler block that
mates to the wing needs to be sanded to the wing bottom profile.
That is done by mounting the wing in the wing saddle and then
performing the final shaping of the filler block mating edge.
Balsa sheet is used under the stab to fill the area between the stab
saddle and the fuselage sheeting.
Glue the rear tail block to former 13 and shape the block.
Use cowl parts C3T and C3B for this step. Place 3CT on top of the
forward internal fuselage box just forward of former 3. Mark the
location of the notch in C3T where it strikes the top of the internal
fuselage box. Remove C3T and glue the cowl retaining lug stand
off to the fuselage box and former 3T using the mark as the
location guide. Glue the lug face to the stand off. Repeat the
process with C3B on the bottom of the fuselage box.
28.
Using the templates provided on the plan, cut the 1/16" balsa
sheeting for the cowl halves.
After the sheeting has been applied to the cowl halves, glue the
nose block laminations together. A 1/16" plywood half ring is
glued to the front face of each nose block half. Glue the nose
block halves to their respective cowl halves. The nose blocks are
then shaped and the cowl halves are final sanded.
29. 30.
31. 32. 33.
34. 35.
There are four pairs of 1/4" x 1/8" magnets that are used to
retain the cowl. Install the magnets at this time. Glue a magnet in
each of the holes in the lower cowl half keel parts. Place a
magnet on the installed units. Mark the outer face of the second
set of magnets. One at a time, remove the second magnet and
glue it in the corresponding hole of the upper cowl half. The
marked face will go toward the inside of the cowl half.
The motor can now be installed. Mount the motor to the internal motor mount box. Make sure the orientation of the motor mount box is
set so the motor will have right thrust. Slide the motor mount box into the outer box that is attached to the fuselage. Place the cowl on
the model. Slide the motor back until you have the proper clearance between the spinner and forward edge of the cowl. Carefully
remove the cowl and mark the location of the motor mount on the motor mount box. Apply some epoxy to he outer faces of the motor
mount box and slide it back onto the outer box on the fuselage to the marks. Before the epoxy sets put the cowl back on to make sure
the spinner gap is still correct.
The finished cowl is installed on the fuselage by placing the back
face of each half against fuselage former 3. Each half is then slid
vertically until the bottom edge of the rear cowl formers engage
the retaining lugs on the fuselage. The magnet pairs keep the cowl
from separating in flight. To remove the cowl simply slide each half
up and down to disengage the retaining lugs.
C3B
C3T
Mark Here
Build the cowl halves by placing the cowl keel parts over the
plan. The upper cowl half keel parts have wider notches in the
middle. Glue the formers to the keel parts. Add 3/16" balsa
stringers. For the upper cowl half, the stringers need to be two
pieces. This will eliminate bending stress that can distort the
upper cowl half.
Note: There are 2
C2T formers
Mark this face