Symptom

Scratch marks appear randomly on solid images in the paper feed direction.

Condition

The problem is likely to occur under the following conditions:

  • Coated paper
  • Paper containing a lot of paper dust
  • More noticeable on solid images
Cause
  1. Toner accumulates on the ribs on the transport guide plate adjacent to the cooling pipe.
  2. Scratches, paper dust, contamination on the transport guide plate

  • Although the transport guide plates have PEFE sheets attached [A] to prevent foreign materials from adhering, the problem cannot be completely avoided.

Problem Mechanism
  1. Due to the low melting point of the toner used for this series of machines, toner is easy to be scratched by extraneous materials
  2. Tight curve of the switchback exit path causes the paper to contact the guide plate.
 

MPC7501/6501

Pro C5200S/C5210S

ProC751EX/651EX

Curvature

Average R35

Average R50

Average R70

Supported paper (gsm)

Straight: up to 300gsm

Switchback: up to 163gsm

Duplex: up to 163gsm

Straight: up to 300gsm

Switchback: up to 256gsm

Duplex: up to 256gsm

Straight: up to 300gsm

Switchback: up to 256gsm

Duplex: up to 256gsm

Toner

CER

SPR-F2

(Low melting point)

CER-gamma

Comparison with MPC7501/6501

Advantage: Curvature

Disadvantage: Support for thicker paper, Toner

Comparison with ProC751EX/651EX

Disadvantage: Support for thicker paper, Toner

- Transport layout competition among 3 machines -

[A]: Cooling roller

[B]: Fusing

Action 1 (for scratch marks originating in the ribs of the guide plate adjacent to the cooling pipe)

Clean the ribs on the guide plate.

Action 2 (for random scratch marks originating in the guide plates)

The following explains the location requiring cleaning when scratches are generated, depending on how the copies are delivered; face up/down, simplex/duplex.

  • If scratches appear on straight-fed simplex, or the second side of duplex prints, clean the upper part of the paper exit transport path as shown below.

    [A]: Paper Exit Upper Guide Plate
  • If scratches appear on the first side of duplex prints, clean the lower part of the paper exit transport path as shown below.

    [A]: Fusing Exit Guide Plate
    [B]: Heat Pipe Entrance Guide Plate
    [C]: Paper Exit Junction Gate
    [D]: Transport Ribs (22 positions)
    [E]: Paper Exit Guide Plate (Clean this area thoroughly.)
  • If scratches appear on simplex prints made with face-up delivery, clean the lower left part of the paper exit transport path as shown below.

    [A]: Paper Exit Lower Left Guide Plate (Clean this area thoroughly.)
    [B]: Paper Exit Lower Right Guide Plate
    [C]: Junction Gate Ends
  • If scratches appear on the second side of duplex prints, clean the duplex unit as shown below.

    [A]: Duplex Transport Guide Plate (Upper): Clean the turning point on the right thoroughly.
    [B]: Duplex Transport Guide Plate (Lower)