If you don't want to use steam to bend plywood, your only other choice is to kerf cut the plywood. Kerf cutting is a fairly straight forward method of bending or creating curves in plywood in which notches or cuts are made in the plywood, allowing the wood to bend. Kerf cutting requires attention to detail and patience.
Determine the radius of the curve or bend in the plywood. The angle of the bend is a vital factor in this process. Find the point in the plywood where the centre of the curve will be. Do this project on a sample or extra piece of plywood first. The cutting of kerfs is a precise technique. From the curve centre measure the length of the radius on both sides. For example if the radius of the curve is three inches, the plywood will be marked three inches from the curve on both sides of the curve centre.
Mark the placement of the kerf cuts. Start at the centre of the curve and move outward every ½ to 1 inch. The smaller the gap between kerf cuts, the smoother the bend will be. If you are not comfortable with kerf cutting, start with every inch.
Cut the plywood. Almost any type of saw can be used to cut kerf cuts. If you are using a skill saw or hand saw, use a straightedge guide. A radial arm saw works great for cutting kerfs and it uses much less energy to cut the wood. Kerfs are cut on the back or underside of the wood and are cut to two-thirds the total depth of the wood. This leaves 1/3 of the plywood on the top to bend. The cuts are made vertical into the depth of the plywood. The cuts do not need to be wide. The width of the saw blade is sufficient.
Place wood glue inside the curve and in all the cuts in the plywood. Clamp the plywood into the bend or curve and allow the glue to dry. Wood glue normally sets overnight.
Repeat the process on the plywood for the project once you feel comfortable making the kerf cuts.
The kerf cutting process is used to make curves and bends all types of wood and timber.
Do not make kerf cuts more than two-thirds the depth of the plywood. This causes the wood to crack and break.