Each grid measures 14inches, so it is bigger than 120cm x 60cm
Add 12 inches to the length and width for cutting dimension
Add 12 inches to the length and width for a 6 inch wall all the way round. This gives you the outer dimensions to cut. If the cage is going against a wall, you may want to make the back wall 12 inches high to help prevent hay spillage. In that case, you'll add a total of 18 inches to the original measurement from above, for one 12" side.
So,using the above measurements, you should get:
53" x 39" for a 2 x 3 grid cage
68" x 39" for a 2 x 4 grid cage
83" x 39" for a 2 x 5 grid cage
96" x 39" for a 2 x 6 grid cage
(96" is a full sheet length-8 feet)
Taken from
http://www.guineapigcages.com/howto.htm
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