Howard Ike DGA-5
Photographed here is how the trailing edge and rear corner of the wing tip are shimmed up with ¼-inch balsa to ensure the wing goes together straight (above
accurately the wing will have zero incidence. When finished, protect the trailing edge
with a layer or two of wax paper, reinstall the wing and use it to position and glue in the wing mount block. The wing mount block is a short length of ¹⁄₂-inch square hard balsa or basswood, sanded on one side to match the wing joint shape. Finally, drill and tap the block through the hole in the wing’s trailing edge and install a 10–32 ny- lon screw to secure the wing. With the wing secured in place, install the
FW formers to the bottom of the wing. They are all basically the same shape since the fuselage has a fairly constant cross-section here. But the wing surface is curved so you need to trim them where they meet the wing. The front and rear FW formers should match the fuselage formers and the middle FW for- mers should be shortened as required so the stringers in this area are straight. Install ¹⁄₈- inch square balsa stringers. Cut one away between F2W and F3W and make a hole in the bottom sheeting to allow access to the aileron servo. Laminate the wing mount bolt seat area with a piece of ¹⁄₁₆-inch ply. Tail: The stabilizer, elevator, rudder and vertical fin are constructed very simply with ¼-inch balsa frames filled in with ¹⁄₈ × ¼- inch balsa stick ribs. Just cut out and lay the frame pieces over the plans on a flat surface, glue them together, and fill in the ribs. Block
left). Now the top spar cap and turbulators have been added (above right). The wing can be removed from the board once the gluing at this stage cures.
sand the open surfaces flat and round out the leading edges of the stabilizer and verti- cal fin, and the trailing edges of the rudder and elevators. Bevel the leading edges of the elevators and rudder. Leave the trailing edges of the stabilizer and vertical fin flat. Bend a ³⁄₃₂-inch elevator joiner wire, drill
and notch the elevators so the joiner wire lays flush with the leading edge, and install with epoxy or thick cyano. Make sure the el- evators lay flat and their leading edges are in line before the glue dries. An easy way to do this is to press this assembly up against the stab with some wax paper protecting the stab. You can temporarily install control horns at this point and glue or screw them in place later after covering. Pin the horizontal stabilizer in place on
the fuselage and check that it lines up hori- zontally with respect to the wing. Sand the stab mounting area on the fuselage if neces- sary to square things up. Tack glue some scrap ¹⁄₄-inch balsa spacers to the fuselage to substitute for the fin and stabilizer and tack glue a couple of soft balsa blocks in place for the tail fairings. Sand these to shape to fol- low the curve of the fuselage. Carefully re- move the fairings and scrap spacers. Glue on the stabilizer and fin and replace the fair- ings. Check that these are straight and true before the glue dries. Temporarily hinge the rudder and eleva-
tors in place and install the servos and tail pushrods. Fill in between the stringers with ¹⁄₃₂-inch sheet where the pushrods exit, and slot for the pushrods. Bend a piece of ¹⁄₁₆-inch music wire to
shape for the tail skid and install it into a hole drilled into the lower rear longeron. Stiffen this area by laminating with strips of scrap basswood or ply and wrap with thread and glue. Landing gear: Cut and bend ³⁄₃₂-inch mu-
sic wire to form the landing gear legs as shown on the plans. Slip these into the brass tubes in the fuselage and wing and tem- porarily bind them at the bottom with fine wire or thread. Now do final adjustments to their shape and position to get the axles lev- el, even, and positioned directly under the leading edge of the wing. When satisfied with their shape and position permanently bond the legs together with fine wire and solder. Clean the wire before bonding for a good joint. They are held in place in the wing by #2 screws driven into the ply wing join- ers. The front wires are held in place by a small rubber band looped around the top of each leg. If you need to remove the wing of- ten then the rear legs can be restrained with a rubber band as well. Wheel pants: Laminate the wheel pants
as shown using ¼-inch and ¹⁄₈-inch balsa. The outlines shown will result in a hollow
Close-up of the rear landing gear tube (above left). This brass tube nestles neatly in the groove formed by the 3-piece plywood wing joiner lamination. Note
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the wing mount dowels are firmly anchored in this ply laminate. The aileron pieces key together (above right) to form a stiff lightweight structure.
MARCH 2012
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