HP 2100 Service Manual - Page 51

Envelopes should have a diagonal grain, which gives them the best stability. To determine this, cut a square section from one corner of an envelope. Wet this section and observe the manner in which it curls. Two opposite corners should curl toward each other. Figure 2-2 Long, Short, and Diagonal Grain Curl Curl Field Test To check for paper curl, place a single sheet of paper onto a flat surface and measure curl at the greatest deflection, holding a ruler perpendicular to the flat surface. Figure 2-3 Measuring Curl Cut Edge Condition Field Test The condition of the cut edge can be easily observed with an eye loop. Under magnification, a good edge will appear even. A poorly cut edge will show fraying, jagged edges, compressed fibers, and other damage. Furnish (Fiber Composition) Field Test Specification: Use paper made form 100% chemical wood pulp and /or cotton fiber. Recycled paper made with no more than 5% groundwood is also acceptable. Read the ream label to determine the fiber composition of the paper. Paper is usually specified as xerographic bond (suitable for copiers or laser printers) or cotton bond. Cotton bond paper of 25%, 50% or 100% will be indicated on a watermark. If paper is less than 25% cotton bond, the watermark will not indicate a percentage. A wood pulp test kit may also be used to test fiber composition. C4170-90959 Media Specifications 41