How to Solve the Problem of Ghosting and Image Dislocation in Riso ComColor Machine's Printing

Generally speaking, after using the COMCOLOR machine for a period of time, the printed image will have ghosting and image dislocation, as shown in the figure below:

The reasons for such problems are generally the quality of the ink cartridges and the failure of the machine itself. 

Below we use the troubleshooting method to find out the real cause of the machine failure:

I. First of all, let's check the ink cartridges that are being used on the machine for ink leakage. If the ink cartridge itself is dripping or leaking, we need to open the front door of the machine immediately, check the BP unit, and see if there is ink leaking on the surface or edge of the belt. If there is ink leaking on the surface of the belt, it will cause the belt rollers to slip, which will cause the printed product image to be misaligned. At the same time, we need to check whether the cable connecting the BP unit is connected correctly. If the cable falls off, it will also cause the printed product to become image misaligned.

II. Secondly, we need to check whether the paper box of the machine is in good condition. If the spring on the paper box falls off or the lever is misaligned, the paper will be fed unevenly during the printing process, which will also cause the printed product to become image dislocated.

Through the above situation, we can basically confirm the real cause of the dislocation of the printed image.

After confirming the cause, we can then correct the position of the print head by adjusting the speed of transfer belt motor, the speed of paper elevation motor and the speed of registration motor, so that the printed image can be aligned. Specific steps are as follows:

    1. Press *#8 three keys at the same time to enter the maintenance mode

    2. Enter password 3214

    3. Enter order code: 1786

Check the transfer belt motor speed value. The default value is 0 ms. In general, the value range is (-196ms-665ms). Through step-by-step adjustment (lifting adjustment) this value, a suitable value is finally determined.

    4. Enter order code: 436 to print out all the color values of the print head in the Y direction to confirm the position of the print head.

    5. Enter order code: 435 to print out all the color values of the print head in the X direction to confirm the position of the print head.

Repeat the above steps, input 1787, 1802, 1803 one by one, and correct the position of the print head by adjusting the speed of the paper elevation motor and the registration motor, so that the printed image can be aligned.

The following contents are cited from the maintenance manual: