Now an article about designing balsa wood glider. Using the modeling
knife, cut out the parts from the plan. Work carefully, taking multiple passes.
The wood will cut or split easily along the grain and will be much more
difficult to cut across the grain.
Sand the pieces into their final shape. Because the model is made from solid
pieces of wood, rather than from a covered frame, most of the shaping of the
structure will come from sanding. Start with the edges but avoid for now edges
which will be glued together later (the inner edge of the two wing halves, the
bottom of the vertical stabilizer and the places on the fuselage where the wing
and horizontal stabilizer will be mounted). You can hold identical pieces, like
the two halves of the wing, together as you sand so they maintain an identical
shape. Once the edges are sanded, you can turn to the surfaces. Using medium
grade sandpaper, sand the fuselage and the tail pieces until they are smooth to
the touch.
Sand an airfoil into the wing. The airfoil of a wing, along with its angle of
attack, is what provides the plane with "lift." The airfoil shape should make
the wing rounded along the leading edge, widening toward the center and then
tapering almost to a point at the trailing edge.
Sand the inner edge of each of the wings to an angle that will create
"dihedral" nvktazrew when the two halves are glued together. The amount of
dihedral should be marked on the plan and is measured as the distance each
wingtip is from where it would be if the wing were perfectly flat. With the
wing's leading edge facing away from you, prop up one half of the wing with a
small block so the wingtip is at the proper height. Take a sanding block and
place it vertically against the inner edge. Sand until the edge is perfectly
flat and perpendicular to the work surface. Repeat with the other wing half.
Glue the two wing halves together. Using blocks under both wingtips to create
the proper dihedral, apply a bead of glue to the inner edge of each of the wing
halves. Press the two halves together. Remove the excess glue. Place a light
weight on the wing near the center joint to hold it in place. Measure the
dihedral again and make any necessary adjustments. Let the glue dry for a couple
of hours
Assemble the plane. Pay special attention to the angle of the horizontal
stabilizer relative to the angle of the wing (this is called wing incidence).
Check your parts against the plan to be sure the proper angles are maintained as
you build. If the wing incidence is incorrect the model will fly poorly. Let the
glue dry for a couple of hours.
Balance the plane. Place a finger on the bottom of each wing half, roughly in
the middle of the width of the wing. Balanced this way, the plane will tip
toward the tail. Add modeling clay for weight on the nose of the plane until you
achieve a level balance.
Test fly the plane. Holding the plane at shoulder height, with the nose
angled slightly downward, gently push the plane as you release it into the air.
Don't throw it or toss it. The glider should fly fairly straight on a nice
smooth, steady path.
Trim for the perfect flight. If the plane dives out of your hand, remove some
nose weight. If the plane flies sharply upward then stops (stalls) and flips
downward into a dive, add more nose weight. If the plane veers sharply to the
right or left, gently bend the back edge of the vertical stabilizer to
compensate for the turn until the glider flies fairly straight.
Balsa can be purchased from most craft stores, but better quality and a wider
selection of sizes will be available at a hobby shop.
For the longest possible flight, the plane can be thrown hard nearly
vertically into the wind and then circle back to the ground. This type of flying
requires special trimming.
Be patient while trimming the model and change only one thing at a time until
it flies the way you want. By the way , we offer you large number of balsa
rectangle ,you can take a look.
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