Picture frame corner protectors protect the corners of a picture frame from nicks and scratches that could damage its surface. Most picture frames are made out of wood, plastic or metal and usually come with corner protectors when purchased. People often remove these corner protectors from their new picture frames; however, you might want to consider leaving them on or creating your own, especially if the frames are valuable and located in a place where they could be easily damaged or knocked.
Measure the width of the picture frame.
Cut eight equilateral cardboard triangles that measure 3 inches on all sides.
Cut eight rectangular pieces of cardboard that are 3 inches long and as wide as your picture frame (use the measurement from step 1).
Lay one cardboard triangle on a flat surface with the “L” of the triangle facing the left.
Glue one rectangular piece length wise onto the left hand side of the triangle. The rectangular piece should be facing upward.
Glue one rectangular piece to the bottom leg of the triangle. The rectangle should be facing upward.
Glue another triangular piece to the top of the pieces you have already glued. The triangle should be the lid of the structure.
Leave to dry.
Repeat this process with the remaining cardboard pieces.
Place the cardboard corner protectors onto the picture frame corners after the glue has dried.