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Museum Macchi 202 looking brand new and as elegant as ever in its resplendent camouflage pattern (above left). Another 202 in the Smithsonian Air & Space Musuem, this time in a more realistic position (above right). The aileron hinge support is embedded in the foam wing


core (below left). The top sheeting fully captures it. Z-Poxy Finishing Resin bonds the balsa sheets to the core. Weights, including the author’s spouse’s antique sewing machine, molds the sheeting in place during the curing process (below right).


Cut the landing gear doors from K&S .032


sheet aluminum. Drill the six ³⁄₃₂-inch diam- eter holes. Modify the Robart clamp 670DB as shown on the plans. Assemble the clamps on the Robart strut 670 and install them into the retract. Add the Du-Bro four-inch diameter wheels and screw the assembly to the landing gear box. Attach the landing gear door and activate the retracts with a hand pump. Adjust the location of the clamps and door and bend the door until it follows the airfoil as closely as possible in the retracted position. Sand and shim where necessary. Remove the assembly and apply four-ounce fiberglass cloth around the entire retract cutout. Apply two layers to the ex- posed portion of the top wing skin in the wheel well. Make a groove along the chord line at the


root of each wing panel for the ⁵⁄₁₆-inch di- ameter wing dowel. Mark the location of the servo wire channel on the top wing skin. Use a ¼-inch long shaft drill to open up the chan- nel for the air hose. Epoxy the wing halves together, leaving that groove as clear as pos- sible. With five degrees dihedral at the joint, there should be 3½ inches at the end of the foam. Recess the wing leading edge to re- ceive the ¹⁄₈-inch plywood wing dowel sup- port. Clean out the hole in the dihedral joint for the wing dowel with a ⁵⁄₁₆-inch diameter drill.


Use Gorilla glue to secure the wing dowel and wing dowel support in place. When dry,


FLYING MODELS


shape up the leading edge of the wing. Wrap the dihedral joint with six-inch Sonictronics fiberglass tape out to the point shown on the plans. This will allow for a 1½-inch overlap at the joint. Open a hole through the foam for the aileron servo wires. Use three-inch tape on the bottom. Put the wing aside and start on the fuselage. Cut the fuselage sides from ¼-inch balsa.


There are dimensions on the plans to assist you. Epoxy the ¹⁄₈-inch lite ply doublers and the ¼-inch balsa doublers to the sides. Glue the ½-inch triangular balsa stock to the bot- tom edge. Epoxy the ¼-inch square spruce support pieces for F3 in place. Epoxy the ½ × 1-inch maple wing screw blocks in place. Cut F1 from ½-inch plywood and F2 and F3 from ¹⁄₈-inch plywood. Cut the motor mount for the Brison 3.2 from ¾-inch maple. Drill a recess for the 10–32 T nuts into the


motor mount ¼ inch deep from the rear side. Drill a clearance hole for the nuts and press them in place. Check them for a good fit with the engine. Epoxy the motor mount to F1 and use four #10 flat head wood screws in- serted from the rear of F1 to secure it in place. Epoxy the fuselage sides to F1, F2 and F3. Check the fit of the assembly against the wing before the epoxy cures. Epoxy the ¼ square spruce cross piece to the rear of F3. When cured, glue the tail end together with the balsa tail block in between, constantly checking the alignment. Glue the F1 and F2 scrap balsa fillers in place.


Place the wing in the wing saddle. With


the wing alignment exactly right, epoxy the ¹⁄₂ × 1-inch maple fuselage wing dowel sup- port to the front of F2. When cured and with the wing still in position, drill from the bot- tom of the wing through the screw blocks with a ³⁄₁₆-inch diameter drill. Make the en- try in from the bottom of the wing very ac- curately and be sure that you are drilling perpendicular to the bottom of the wing. Re- move the wing. Enlarge the holes in the wing to ⁵⁄₁₆-inch diameter. Thread the blocks with a ¼–20 tap. Cut


out the ¹⁄₈-inch plywood wing screw supports and drill a ¼-inch diameter hole through them to provide a tight fit around your ny- lon wing screws. Place the wing on the fuse- lage again and realign it. Mount the screw supports on the screws as if they are large washers. Spread epoxy on the supports and screw the assembly through the wing and into the blocks. Check the alignment again before the epoxy cures. When cured, turn the assembly over and


epoxy the ³⁄₈-inch square spruce wing stabi- lizing blocks to the wing while held firmly against the screw blocks. Epoxy the ¼-inch lite ply insert to the bottom of the fuselage for the tail wheel bracket mount and the ¼- inch plywood mount in place. Also glue a piece of ¼-inch balsa three inches wide in front of that assembly. Remove the wing when the epoxy has cured. Cut the top and bottom formers from their


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