To build a wooden flag display case, create grooves in an 8-foot long lumber piece, and cut it into three pieces to a size that can accommodate the folded flag. Cut the luan to the required size, buy a suitable piece of glass, and join the pieces to make case.
Begin making the wooden flag display case by measuring the sides and depth of the folded triangular flag. Adjust a table saw to a depth of 1/8 inches and set the space between the blade and the guard to 1/4 inches. Run the lumber piece through the saw two times to form a groove on it.
Cut the lumber into three pieces with their inner lengths equivalent to the triangle's dimensions. Cut the wood at an angle of 45 degrees, with its ends pointing in opposite directions. Use the three lumber pieces to measure the required luan size, and cut accordingly. Alternatively, use an angle tool and ruler for this purpose. Use the cut luan's dimensions to buy a piece of glass of the same size.
To make the flag case, nail the three lumber pieces at each corner. Insert the luan piece and the glass into the grooves. Place the folded flag when assembling the case. Apply putty over the nails and stain the wood. If desired, attach trim around the case's perimeter.