Ends
Even
Step 15 - Apply wood glue fillets between the body tube, wing
and horizontal stabilizer. Smooth and remove excess glue with a
fingertip.
Step 16 - Cut out the fin pod alignment template. Wrap it
around the body tube in front of the wing. Align the center line
mark on the template with the center line of the wing. Mark the two
pod fin locations on the body tube.
Step 17 - Using a door jamb or
section of angle stock, pencil a line
down the body tube on the pod fin
alignment marks.
Step 18 - Similarly pencil a single line on each of the pod body
tubes that extends from the front to the middle of the tube length.
This is used later to align the pod fins.
Step 19 - Glue two of the 1/8" x 1/4" pieces side by side
forming a long 1/8" x ½" section. Let dry.
Cut the assembly to 19 3/4" long.
Step 20 - Cut two 7 ½" long pieces from the remaining 1/8" x
1/4" balsa stock and glue these side by side to form a 1/8" x ½"
section.
Step 21 - Glue the 7 ½" section under the front end of the
longer section. Be sure the front and sides are even and smooth.
Step 22 - Mark the back end for the stabilizer slot as shown.
Using a sharp knife cut out the slot.
Step 23 - Mark the two layer front end 1 1/2” from the front.
From this 1 1/2” mark, round and taper the end. Cut the sides
profile first, then round over the top.
Do the same with the back end. The front end is double height, the
notched back end is a single thickness.
1 7/8”
1/8”
Overhead View Aft
Overhead View Front
Step 9 - The shock cord in this kit consists of a shorter section
of yellow Kevlar and a longer section of white nylon cording. The
two sections should be tied together using a single overhand, ring
bend or double fisherman’s knot. The yellow Kevlar section is
attached to the motor mount and the yellow nylon section will be
attached to the nose cone.
Step 10 - Wrap the shock cord in a small bundle and stuff it
inside the motor tube for the next step. Test fit the motor tube
assembly in the aft end of the body tube to insure a snug fit. Sand
the centering rings if necessary.
Step 11 - When you are satisfied with the fit, spread some
wood glue inside the body tube about 2 1/2" from the aft end.
Make sure you have the motor assembly facing the right way -
The centering ring with the Kevlar tie should slide in first.
Slide the forward centering ring of the motor mount assembly into
the body tube. IMPORTANT: Make sure the shock cord passes
through the notch between the centering ring and body tube.
Spread more glue on the inside of the body tube near the aft edge
before sliding the rear centering ring into the body tube. Continue
sliding the assembly into the body tube until the aft end of the
motor tube is even and lined up with the aft end of the body tube.
It’s up to the builder - The wing, horizontal stabilizer and rudder
edges can be left square or rounded. Don’t round any edges that
will be glued.
Step 12 - Mark the center of the front and rear of the two wing
pieces, the horizontal stabilizer and the spacer. Note that the
spacer is the longer of the 3 bass wood rectangle. The shorter
rectangles are used on the pod fins later in Step 27.
Step 13 - Using a flat surface and straight edge, apply wood
glue to join the four basswood pieces as shown in the drawing.
Make sure the drawn center lines are lined up with each other.
Use a straight edge to check the alignment.
Step 14 - Apply a line of wood glue down the centerline of the
fin assembly shown in the drawing below. Make sure you don’t
allow any glue to get into the slot in the horizontal stabilizer
because it will be difficult to clear later. With the engine mount
assembly to the rear, press the body tube into the glue ensuring
the tube is aligned on the center marks drawn earlier.
IMPORTANT: Make sure the end of the body tube is even with
the end of the horizontal stabilizer.
See illustration on next page . . .
Insert Motor Tube Assembly into the Body Tube
Tube Ends Even
Fin Assembly
Longer
Spacer
Yellow End to
Engine Mount
White End to
Nose Cone
Mini Bomarc Assembly
©
2015 Madcow Rocketry™