Brother GT-3 Series Service Manual page 155

6. Replacing Parts
<Reference>
If the actual print position is top margin = 5 mm and the bottom margin = 9 mm, then move the Platen
Sensor Dog to the backward by 2 mm then the both margins will be 7 mm, increasing the top margin by 2
mm and decreasing the bottom margin by 2 mm.
4.
Adjust the top/bottom margins almost equal, the differences within 3 mm, by repeating the step (2) to (5)
in the above.
5.
Mount the Cover PF and Cover DL. (Refer to "6-1-2. Assembling/Disassembling of the Covers".）
146
9
Move the Platen
Sensor Dog backward
by 2mm
5
GT-3 Series
7
7