This rocket uses:
- BT-50 Tube 5" Long
- BT-55 Tube 5" long
- BT-50 to BT-55 centering Ring (2)
- BT-50 to BT-60 Centering Ring
- BT-50 Thrust Ring
- "E" motor Clip
- Two BT-5 nosecones (BNC5E and BNC5AX from Balsa Machining)
- 1/4", 1/8" and 3/16" sheet Balsa
- 5/16" birch dowels 12 3/8" long (2)
- 3/16" launch lug
- Lead Sheet for weight
- Heavy Kevlar Cord
The construction begins by cutting out a fuselage profile from 1/4" balsa. Cut out the nose weight area and fill with lead sheet. It is important to get as much weight forward as you can. Cut a groove in the 1/4" sheet and glue in the shock cord with epoxy or slow CA. When done sandwich the lead and Kevlar in place with profiles cut from 1/8" balsa. Press under books and let dry.
While that dries, cut out and glue up the three pieces that make up the side panels. Be careful to get the grain direction correct for maximum strength.
Glue the thrust ring 3 1/4" from one end of the BT-55. Cut a 1/8" slit behind thrust ring and insert engine hook. Hold it in place with tape.
Cut slots in one 50-55 ring and in the 50-60 ring to clear engine hook. Slide the 50-55 ring onto the rear of the tube, over the hook, and glue it 5/8" from the rear of the tube. Butt the 50-60 ring against it, and glue in place.
Cut a slot in the remaining 50-55 ring deep enough to clear the shock cord. Thread the shock cord through the BT-55 and glue it into the fuselage profile centered in the slot. Thread the Kevlar through the 50-55 ring and glue it to the entire length of the engine mount with epoxy or thick CA. Glue the 50-55 ring flush to the front of the tube.
Glue the assembled sides to the body and the main tube.
Block off the end of the BT-55 tube with scraps of balsa.
Enclose the main tube with the Nacelle parts. Cut the parts from the patterns in 3/16" balsa and rough in the shapes. Fit the cockpit sides over the Nacelle covers and to the sides - bevel the edges of the parts as needed for a good fit.
After the shape has dried, begin roughing it in with 50 grit sandpaper, forming the final shape. Refine the shape and work with finer and finer grit papers until you have a fairly smooth shape sanded to 100 grit.
Fill the gaps in the rear of body with scrap balsa.
Using Elmer's carpenter's wood putty, fill and smooth the shape giving it the curved look. Keep sanding and filling until you get the shape where you want it. At the same time cut out and fill all the remaining fin shapes
Cut the shoulders off the nosecones and glue them back-to-back. Fill and seal them with the fins.
Bevel the 50-60 centering ring to accept the paper tailcone and attach it.
With the two 12 3/8" dowels, make three marks from the back at 1/4", 2 7/8", and 4 1/4" from the back.
Tack the dowels to the fuselage with the 4 1/4" mark at the back of the fuselage.
Tack the nosecones to the top of one tailfin with thin CA, (You may need to "cup" the top of the fin for a good fit).
Tack glue both tailfins to the nosecones and the dowels between the two remaining marks. Check your alignment, and adjust if needed.
Tack glue the lower tail fins and wings to the dowels. I canted the wings downward to a bit more than in the drawing - it looked more stable that way. Once you are satisfied with the fin positions fillet everything with thick CA for a final glue joint.
Glue a 3/16" launch lug along the bottom centerline.
Jim Bassham (May 3, 2011)