Building a balsa wood glider is a fun and interesting way to learn about the physics of flight. Balsa wood is a lightweight flexible wood that is easy to work with, and its light weight will allow your glider to fly through the air with very little energy put into it. In order to make a balsa wood glider from scratch, you will need to put a bit of time and effort into the design of your glider; the end result, however, will be a glider that you can show off to your friends and family.
Draw a pattern for your balsa wood glider's fuselage on a piece of paper before cutting into the balsa wood. Draw the fuselage so that it is 12 inches long and 2 inches wide. The fuselage should have a rounded nose in the front (like the front of an aeroplane) and a vertical stabiliser extending above the tail end of the glider. The vertical stabiliser should have a height of 2 inches and a width of 2 inches.
Draw a pattern for the glider's wings. The wingspan should be 12 inches total (6 inches extending from each side of the fuselage) and the width of the wings should be 2 inches. Draw the wing pattern so that the front corner on each side of the wing is rounded. The tip of each wing should resemble a shark fin.
Draw a pattern for the glider's horizontal rear stabiliser. The length of the horizontal rear stabiliser should be twice the height of the vertical rear stabiliser, or 4 inches, and its width should be 2 inches. Draw the horizontal stabiliser pattern like you drew the wing pattern (with rounded front corners) so that the sides of the stabiliser resemble shark fins.
Cut out the patterns, place them on top of the balsa wood sheet and then pin them in place with the sewing pins. Cut around each pattern with the utility knife, making sure to cut all the way through the wood. Once you have cut all the way around each pattern, punch each shape out of the wood sheet.
Lay out the fuselage section in front of you. Mark the exact centre of the fuselage with a pencil. Place the protractor over the centre of the fuselage and make a mark on the fuselage at the 7-degree point on the protractor with a pencil. Use the ruler to make a 2-inch line that passes through both of these marks. Cut a slit along this line that is 2 inches long and 1/16 inch wide. The slit should go up slightly at a 7-degree angle toward the front of the glider.
Insert the wing section into the slit made in Step 5 so that the wings extend out equally on each side of the fuselage. Apply a small amount of glue to the perimeter of the slit to hold the wings in place.
Cut a slit that is 1 inch long and 1/16 inch wide, 2 inches beneath the tip of the vertical stabiliser. Cut a slit that is 1 inch long and 1/16 inch wide directly in the centre of the front end of the horizontal stabiliser. Insert the horizontal stabiliser into the slit made beneath the vertical stabiliser so that the slits line up and lock together. Apply a small amount of glue to the connection to hold the horizontal stabiliser in place. Let the glue dry thoroughly before moving onto Step 8.
Throw the glider with a gentle flick of the wrist. If the nose of the glider lifts, attach some paper clips to the front of the glider to add some weight. Toss the glider again. If the nose lifts, add weight; if the nose dives, remove weight. Continue to add and remove weight until the glider flies straight without diving or lifting.