How to Make a Window Frame With a Table Saw

Raise the saw blade up on the table saw. Set the miter gauge at a 45-degree angle using a 45-degree drafting triangle as a guide. Mount an extension fence to the miter gauge, all miter gauges have screw holes or slots for this purpose. Screw a 1x2 straight board at least 12 inches in length to the back of the miter gauge to make an extension fence. Fasten the extension fence with short screws. Create 45-degree angle cuts by holding boards firmly against the extension face and pushing the board through the blade.

Measure the window pane’s height. Add 4 inches to this measurement to compensate for a 45-degree cut. Mark the measurements on the two pieces of wood for the sides of the window frame. Use the table saw to cut the two side pieces of wood at a 45-degree angle.

Cut a downward 45-degree angle on the top of the left-side piece of wood and an opposite downward 45-degree angle on the top of the right-side piece of wood. Make an upward 45-degree angle cut on the bottom of the left-side piece of wood and an opposite upward 45-degree angle cut for the bottom of the right-side piece wood. Sand the two pieces of wood to remove any rough areas.

Measure the width of the window pane. Remember to add 4 inches to the measurement to allow for the 45-degree angle cuts. Mark the measurements onto the two remaining wood pieces. Create the header and sill for the window frame. Use the table saw and make two 45-degree angle cuts on each end. Apply the table saw to the last piece of wood and cut two downward 45-degree angles on both ends, thus forming the window’s sill. Use the sandpaper to smooth out any jagged parts on the wood.

Fit the pieces of the window frame together. Glue the ends of the header and adhere to the top edges of the two sidepieces of the frame. Hammer two finishing nails into place on each end of the header. Position the nails so they join the header with the two sidepieces forming the corners. Repeat this process for the bottom piece of wood to make the window’s sill. Wipe off any excess glue with a damp cloth. Allow the glue to dry for at least 24 hours.

Check the window frame after 24 hours. Fill the corner joints and nail holes with wood filler. Let the wood filler dry -- drying times depend on the manufacturer’s instructions. Smooth the wood fill with sandpaper after it dries. Finish the window frame with a wood stain or paint if desired.