Chopped Strand Mat
hopped Strand Mat (CSM) is a random fiber mat that provides equal strength in all directions and is used in a variety of hand lay-up and open-mold applications. Chopped strand mat is produced by chopping continuous strand roving into short 1.5 to 3 inch lengths and dispersing the cut fibers randomly over a moving belt to from a “sheet” of random fiber mat. A binder is applied to hold the fibers together and the mat is trimmed and rolled. Because of is random fiber orientation, chopped strand mat conforms easily to complex shapes when wet-out with polyester or vinyl ester resins.