HP LaserJet 4v/mv Service Manual - Page 171

7 Troubleshooting Table 7-21 Paper Curl Paper curl is inherent to the laser printing processes, and occurs when paper is subjected to heat. Paper curl tends to relax as the paper cools while resting on a flat surface. The specification for maximum paper curl when the paper is lying flat before print is 5 mm (0.2 inches). Although paper curl cannot be totally eliminated, some steps can be taken to lessen its impact, as suggested in the following table. Causes of Paper Curl Possible Cause 1. Paper Path 2. Paper Surface 3. Paper Storing and Handling 4. Paper Type Recommended Action Try using MP Tray. The recommended printing surface of the page is usually marked on the end of a ream of paper, indicated by a small arrow and the phrase "print this side first." Load paper in the Paper Cassette with the recommended printing surface facing UP (facing down in the MP Tray). Over time, paper assumes the characteristics of its storage environment (in a humid environment, paper absorbs moisture; in a dry environment, paper loses moisture). Paper with higher moisture content will tend to curl more. Evaluate the storage conditions of the paper. All paper is manufactured differently (different textures, moisture content, drying processes, composition, etc.). Change the type of paper being used and re-evaluate the paper curl results. Troubleshooting 7-35