Pg Adjustment - Epson Stylus PHOTO RX640 Service Manual

EPSON Stylus PHOTO RX640/650

5.1.2 PG Adjustment

Described below is the platen gap (PG) adjustment.
Purpose:
Adjust the distance between the head surface and the Paper Guide Front Assy
(platen) properly and adjust the parallelism on the 0th column side and on the 80th
columns side to ensure reliable print quality.
Once the Carriage Assy and/or Adjustment Bushes have been removed or
whenever necessary for any other reason, make this adjustment to correct the
deviation of the platen gap.
Table 5-2. PG Positions
Application for Printing
PG Size
Position (selected from PG flag list for
(mm)
normal/head rubbing)
PG- EPSON special thick paper
1.2
<APG Home> PGPP, Postcards, Matte, etc.
Plain paper
PGtype
<Mechanical 1.7 EPSON special thin paper, SF, etc.
default>
Rubbing with PG1.2 is avoided
Envelopes
PG+ 2.35
Rubbing with PG1.2 and 1.7 is avoided
PG++ 4.2 CD-R printing
Things to be used
Thickness gauge: 1.1 mm (x2)
1.3 mm (x2)
Phillips screwdriver
Adjustment
C A U T I O N
C H E C K
P O I N T
Sequence
Application
Cleaning
CR measurement,
VH detection
CR home position
seek
At ink replacement
Overview
The thickness gauge to be used must be free from dust and dirt
and from deformation. Be sure to clean it before use.
Take care that the Print Head is not soiled or scratched.
To ensure high accuracy of adjustment, install dummy ink
cartridges in the carriage, and move the carriage right and left
by pulling the belt without holding the carriage.
Make this adjustment after installing the mechanism unit in the
Housing Lower. (Install the Linear Scale after adjustment.)
Refer to "4.2.9 Printer Mechanism" (p.53)
With Stylus PHOTO RX640/650, four stages of PG setting are
available by means of the APG Mechanism. However, make
this adjustment with the mechanism in the minimum PG
position (PG-: 1.2 mm).
(Refer to
"4.5.4 APG Assy" (p.64)
Locating hole
Locating hole
Figure 5-1. PG Position at PG Adjustment
Revision B
Revision B
and below.)
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