The fuselage is started upside-down on the building board (above left). The lateral longerons are pinned over the plans and all the bottom formers are glued in place. The lower longerons are glued in place on top and the radio box sides are added into the mid-section which serves to stiffen the assembly. Here you also see the battery tray glued in place. Stringers are being added at this stage (above right). Also shown is the rough-cut wing saddle sheeting and the
plywood landing gear tube support, just ahead of the wing saddle. Close-up of the forward landing gear tube in place on the plywood support (below left). The tube and plywood support should be epoxied into position. Once the stringers have been installed the fuselage is stiff enough to remove from the building board. Here we see the upper formers and motor mount stick have been added and sheeting has been started on the forward fuselage (below right).
are about as simple as they can be. The fair- ings are ¹⁄₄-inch balsa strips and the wheel- pants are laminated balsa plates, cut out to clear the wheels, while providing enough “meat” to allow for carving and sanding into a pleasing streamlined shape. I found thin or medium cyano glue was
perfect for building this structure with a couple of dabs of epoxy here and there for strength, like around the landing gear hard- points and the elevator joiner wire. I used Coverite Microlite iron-on covering and de- cals made on my inkjet printer. The struc- ture does not rely on the covering for strength so the finished weight remains light with this material. Power required for this model is a reason-
able 150 watts using any one of a variety of inexpensive brushless outrunner motors, and a three-cell Li-Po battery of approxi- mately 2200 mAh capacity. The wing load- ing comes out at a relatively lightweight 13 ounces/square foot which yields sporty and predictable performance. Well, enough talking about it.
Let’s get building! Fuselage: Begin by pinning down the side longerons over the plans and gluing in all low- er formers, front and rear lower longerons, and the radio box sides in place. As mentioned earlier, the parts are pretty much self-jigging due to their interlocking slots but check that the formers are straight and square anyway. Then add in the receiver and ESC trays,
FLYING MODELS
which fit into notches in the radio box, and the battery tray which fits into the arches formed by the front three formers. Balsa strips cross- ing F2B and F4B support the battery tray. This is a good time to glue in the plywood landing gear plate, and servo rails, spaced to fit your servos. I made my servo rails with popsicle sticks, but similar-sized basswood or plywood strips would work as well. Install all stringers using ¹⁄₈-inch square
balsa. Trim a ¹⁄₈-inch brass tube to approxi- mately 2¹⁄₄-inch length, and epoxy this onto the ply landing gear plate and F3. Glue two F8a pieces to F8 and glue in rough-cut wing saddle sheeting, either in two layers of ¹⁄₁₆- inch or one soft layer of ¹⁄₈-inch balsa. Leave the final shaping of this wing saddle until later when fitting the wing. When all the glue is dry, unpin the fuselage. Turn the fuselage upright and add on all
the upper formers and upper front longeron. Now is the time to decide on your motor mount, whether it is to be a stick mount or firewall mount. Install either the stick or the ply firewall plate at this point. Note: I used a stick mount for my motor but if you have a firewall mount motor I recommend you install the stick anyway and make it flush with the front of F1T to help support the plate mount. Install the headrest fairing sides and cap.
The fairing sides simply meet at their aft end, and since they are each ¹⁄₈ inch thick they will match the thickness of the fin which will be installed later. Glue in all re-
maining stringers using ¹⁄₈-inch square bal- sa. Before sheeting the fuselage reinforce the landing gear plate joint with epoxy fil- lets above the plate on F3. Sheet the fuse ahead of the wing, and the top back to the headrest with ¹⁄₃₂-inch sheet. Sand the head- rest fairing pieces to match the shape of F10T. Sand the rest of the fuselage smooth and cut out the cockpit using the template shown on the plans. Set aside the fuselage. Wing: Make a spar cap by cutting a piece
of ¹⁄₁₆×¹⁄₂-inch balsa to 20¹⁄₄ inches long. Pin this down and then pin and glue a spar and all the ribs in place to make the left wing. Slide in the bellcrank plate while you install the ribs. Leave the outer end of the spar cap untrimmed and over-length and shim it up as necessary with scrap to contact the spar and the four tip ribs. Glue in the leading edge, trailing edge, and wingtip edges, as well as the aileron hinge edges. Support the trailing edge and rear corner of the wing tip with pieces of scrap balsa ¹⁄₄-inch thick to en- sure the wing goes together straight. Glue in the top spar cap and ¹⁄₈-inch
square balsa turbulator strips along the top front of the wing. Glue in the W2 rib doubler parts and then
sheet the top of the wing from the root rib out to W2. The top spar cap should be trimmed to length at the tip and tapered. When the glue is dry unpin the wing and re- peat this process to make the right wing. Glue in the bellcrank plates and plywood bellcrank plate doublers. Cut the front and
19
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76