A thin iron frame, covered with paper, and connected temporarily with the tympan, by means of joints attached to it and the headband of the tympan, having iron pins to slip into them. The parts that are to be printed are cut out of the paper covering; it turns down upon the paper to be printed, which is laid upon the tympan, keeps it flat to its place, preserves the margin clean, and raises it from the form after it is printed. See Frisket Button.
Each press in a printing office should have five or six friskets attached to it, of at least three sizes — Demy, as the standard size of paper; a size smaller; and a size sufficient for the largest form the press will print, for it is very inconvenient, and a loss of time, when the pressmen have to cover a frisket and cut it out for every form they lay on: and more particularly when regular work is in the house, and the same frisket will answer for many succeeding forms. It is adviseable, where it is practicable, to have the frisket joints at all the presses of one pattern, so that every frisket may be available at any of the presses.
A pressman should never pull an impression from a form, without being certain that the frisket is large enough, and that it does not rest on the edges of the types, which would be destructive to them.