How to Frame & Mat Large Poster Sizes

Festival poster image by Ilija Mitrevski from Fotolia.com

Things You'll Need

  • Wood frame
  • Mat
  • Metal centering yardstick
  • Pencil
  • Precision-cutting knife such as X-acto
  • Glazier points
  • Flat head screwdriver
  • Acid free tape

Large posters come in three basic sizes: 27 by 41 inches, 27 by 40 inches and 27 by 39 inches. Purchase a mat that is 6 to 10 inches larger than the poster's dimensions. The mat is cut to have a surface between 3 to 5 inches to frame in the poster. Either a purchased frame or hand built frame work well to frame the mat and poster. This large of frame is cheaper to make rather than buy ready made.

Instructions

Measure the dimension of the poster. Add anywhere from 6 to 10 inches to the width and height of the poster. Purchase the desired colored mat board in the determined size.

Determine what amount of the poster that will be visible. Some posters have white edges and these need to be covered. Measure the distance of the visible portion both width and height. A minimum of 1/4 inch around the poster will be covered so it can be secured to the back of the mat board.

Place the mat board on a clean surface. Turn the mat board over so the back is facing up.

Place a mark at the center top edge and bottom edge of the mat board. Place the center of the centering yardstick on the mark. Measure from the center and place marks on both sides to indicate the width of the poster that will be visible. Repeat the process on the bottom edge.

Align the mark from the top and bottom of the mat board directly across from one another with the centering yardstick. Draw a straight line from mark to mark. Repeat with the other two marks.

Continue to work on the back side of the mat board. Place a mark at the center of both sides. Place the center of the centering yardstick on the mark. Measure from the center and place marks on both sides to indicate the length of the poster that will be visible. Repeat the process on the other side.

A rectangle will be made where the lines intersect. Line the centering metal yardstick up with one line so the edge of the line is just visible. Push the point of the knife in at the corner and draw it down the metal yardstick until it reaches the next point. Make sure to apply enough pressure to get through the mat board on the first cut. Repeat the process with the other three lines.

Carefully remove the cut piece of mat board from the center of the mat board. Watch each corner so it comes loose without tearing. Use the knife and carefully cut to the corner if it is caught.

Attaching the Poster

Place the cut center of the mat board back into the opening. This will help to keep the poster flat during attachment.

Center the poster over the cut opening on the back side of the mat. Make sure there is a minimum of 1/2 inch of poster edge on each side of the cut opening.

Tape the edges of the poster to the mat board using acid-free tape.

Framing

Remove the backing from the frame, if there is one.

Insert the mat board and poster into the frame with the taped side to the back. Insert the back from the picture frame on top of the mat board. Cut another piece of mat board or add a piece of cut cardboard if no backing came with the frame.

Insert glazier points every 6 inches in the frame directly on top of the frame backing. Push the glazier points into the wood using a flat head screwdriver.

Tips

  • A paper backing on the frame is optional. Use brown packaging paper and cut it so it covers one inch of the frame on all four sides. Glue it down with white glue. Let the glue dry. Dampen the entire paper. Let it dry. The paper will shrink and fit taught over the opening.

    Attach hangers in the desired locations.