Circuit Board Repair and Rework Guide > 2.0 Basic Procedures > 2.6.1 Legend Marking, Stamping Method

2.6.1 Legend Marking, Stamping Method

Printed Board Type: R/F/W/C | Skill Level: Intermediate | Conformance Level: High | Rev.: D | Rev. Date: Jul 1, 1997

Outline

This method can be used to add, change or replace legend and markings on printed boards or printed board assemblies. This method uses epoxy ink and an ink stamp to place the legends on the printed board surface in much the same manner as taking a "finger print".

Acceptability References
IPC-A-600	2.0	Externally Observable Characteristics
IPC-A-610	8.0	Marking

Procedure References
CTC	1.0	Foreword
CTC	2.1	Handling Electronic Assemblies
CTC	2.2.1	Cleaning, Local
CTC	2.2.2	Cleaning, Aqueous Batch Process
CTC	2.5	Baking and Preheating
CTC	2.7	Epoxy Mixing and Handling
IPC7721	2.6.1	Legend/Marking, Stamping Method
Tools and Materials
Cleaner Color Agent/Epoxy Ink Ink Plate Ink Roller Microscope		Oven Peg Stamps Knife Wipes

Procedure

Damaged Legend

Apply legend using a peg stamp.

Figure 1: Apply legend using a peg stamp.

1.	Clean the area.

2.	Scrape off any remaining character or legend with a knife and clean the area.

	Caution Abrasion operations can generate electrostatic charges.


3.	Select the appropriate characters from the peg stamp set or have a special stamp made up.

4.	Mix the epoxy ink. White is the most common color. Spread a thin even coating of the epoxy ink on the ink plate or on a smooth surface.

5.	Gently press the peg stamp into the epoxy coating to coat the character surface.

6.	Gently press the peg stamp onto the desired location on the circuit board surface. (See Figure 1).

7.	Cure the epoxy ink per the manufacturer's instructions.

Figure 2: Completed legend repair.

Evaluation

1.	Visual examination for proper characters, positioning and legibility.