Fractions work: 10 3/4, 3/8 or 10.75. The overlap hides the paper edge; a negative overlap floats the art with a visible gap.
Frame & preview options
in
in
Mat
Frame
Frame size · mat, glass & backing
15 1/2 × 19 in
Mat window 10 1/2 × 13 1/2 in. Cut a custom rabbet at 15 5/8 × 19 1/8 in for easy fit.
Borders: top · sides · bottom
2 1/2 · 2 1/2 · 3″
Visible past the 1/4″ frame lip
2 1/4 · 2 1/4 · 2 3/4″
Outside of frame, approx.
17 × 20 1/2″
Mats per 32 × 40 in board
4
Nearest ready-made frame: 16 × 20 in. In it the borders become 2 3/4″ at the sides, 3″ top and 3 1/2″ bottom.Tighter fit: 14 × 18 in with 1 3/4″ sides, 2″ top, 2 1/2″ bottom.