A means of testing the roller setting of an offset press's ink or dampening ductor roller or form rollers using strips of thin paper or plastic inserted in the nips of the rollers, then pulled out. This method tests the pressure that exists between the two rollers, the size of the nip itself, the hardness (or durometer) of the rollers, and any glazing that may have occurred. There are two varieties of the strip method of roller testing (also called a sandwich method): the three-strip method or the folded-strip method, both of which are based on inserting several "sandwiches" of paper at various intervals between either the ductor roller and its adjacent oscillator, between the form rollers and adjacent oscillator, or between the form rollers and the plate cylinder, and pulling them back out, the ease or difficulty of which provides a subjective but effective determination of the pressure between the rollers. By inserting several sandwiches along the length of the roller nips, uniformity of pressure can also be gauged. (See Three-Strip Method and Folded-Strip Method.)
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