6.4 TASK -- REPLACEMENT OF WHITE BACKGROUND
A piece of white mylar is mounted on the underside of the scanner lid to provide a uniformly bright and clean background for all documents. In time, however, this background may be damaged and will need to be replaced . It is a simple job, but for best results, it requires the efforts of two people.
The goal to keep in mind while performing this task is that you want to provide a clean smooth background which presents no edges.
Equipment, Tools & Materials Required:
•
•AWG 16 wire (about 60 inches long)
•Very sharp small blade utility knife.
Procedure for Replacing White Background:
1.Lift the scanner lid, take out the top pressure rollers and remove the document guide plate.
2.Remove the old background from the document guide, be sure to clean away any debris from the old mounting materials.
3.Place the new background against the plate so that the top edge is aligned with the front roller
4.Peal off the backing tape from the pressure sensitive tape on the white background and secure the top edge to the plate.
5.If misplacement occurs, use a new piece of white background and start again.
6.To help provide pressure against the document so it is flat against the camera window, a bulge or dome is created in the mylar. This is done by placing the length of wire under the mylar, close to the top taped edge. Tape the ends of the wire temporarily. This part is tricky because of the wire underneath the mylar, but it is essential that the taping and the mylar be uniform to prevent inconsistencies in the background and pressure. Remember, you can not remove the tape and start over if there is a problem. Patience and steady hands are required.
7.Once the bottom edge is secure, you can remove the wire by untaping it and pulling it out one side.
8.Now, using the utility knife, carefully trim the mylar and tape away from the openings for the document sensors.
9.Replace the document guide and the top pressure rollers. The procedure is now completed.
