edges of all eight pieces. Glue the fin halves
together as shown in Fig. 5 above. Use pins,
clamps, or weights to hold the pieces in
alignment while the glue dries.
Step 29 Round over only the leading and
trailing edges of the main fins with 320-grit
paper. Do not reshape the fin. Apply a thin
layer of glue to the root edges of all four
main fins, and set aside to dry.
Step 30 Apply thinned filler compound
to the edges and flat surfaces of the fins, and
allow a day to dry. Sand with 220-grit
paper, tac -rag the dust, and inspect the fins
for gouges, voids, or other visible
blemishes. Repeat this step until you are
satisfied with the surface finish.
Step 31 Sand the 18” BT-50 tube with
220-grit paper to remove the glassine
“shine” from the surface.
Step 32 Draw a continuous line down the
length of the main body tube. Mar the tube
at locations 1”, 2.25”, 4”, 7.75”, 9.5”,
10.75” and 12.5” from the bottom edge.
Draw lines completely around the tube at
these locations.
Step 33 Draw lines parallel to the long
line, 1/16” to either side, between the lines
at 1” and 2.25”, and between the lines at
9.5” and 10.75”. These areas represent the
locations for the two launch lugs. Cut strips
of mas ing tape to fit these two areas, and
apply them to the tube to protect these areas
from filler and primer.
Step 34 Slide the Main Fin Mar ing
Guide onto the body tube from the rear, and
align the “LL” mar with the long line
drawn in step 28. Mar the body tube for the
four fin alignment lines, then remove the
guide. Extend these lines from the rear edge
of the tube up to the line drawn at 4” from
the edge.
Step 35 Cut four strips of mas ing tape
1/8” wide and 4” long. Carefully apply these
to the body tube directly over the fin
alignment lines.
Step 36 Slide the Reactor Vane Mar ing
Guide down from the front of the body tube
until it is touching the line at 12.5”. Align
the “LL” mar with the long line drawn in
step 28. Mar the body tube at each of the
eight locations, then remove the guide.
Extend these eight lines from the line at
12.5” bac to the line at 7.75”.
Step 37 Cut eight strips of mas ing tape
1/16” wide and 4.75” long. Carefully apply
these to the body tube directly over the eight
reactor vane alignment lines.
Step 38 Apply thinned filler compound
to the spiral seam on the body tube, and
allow a day to dry. Sand with 220-grit
paper, tac -rag the dust, and inspect the tube
for gouges, voids, or other visible
blemishes. Repeat this step until you are
satisfied with the surface finish.
Figure 6
Step 39 Using the threads of the screw
eye, cut a hole through the center of the
BNC-50Y shoulder. As shown in Fig. 6
above, reverse the screw eye bac out, then
force full-strength glue into the hole. Coat
the threads with glue, then re-thread the
screw eye into the hole. Do not wipe away
the excess glue. Let this dry in an inverted
position (screw eye up) while the glue dries.
Step 40 Apply thinned filler compound
to the surface of the nose cone. Do not get
any filler on the shoulder area. Allow this to
dry a full day, then sand with 220-grit paper.
Main Body Tube Preparation
Main Body Tube Assembly
