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Troubleshooting ink dots
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5. Lay the specimen on a flat surface and position the jig over it so that your chosen
holes are located an equal distance from the center line of the specimen. The jig is
shaped into sections of different widths to aid positioning on the center line on
specimens of different widths. Make sure the jig is positioned so that the printed
text on the jig is readable and the countersink on the holes is towards the specimen
surface. The countersink prevents the ink from running between the jig and the
specimen.
6. Apply the ink through the holes making sure that the dots are round and of an even
density:
a. Keep the marking pen upright.
b. Apply minimum pressure to the pen.
c. Run the pen around the edge of the hole twice, then fill in the center.
d. Apply all the marks without disturbing the jig.
e. Apply sufficient ink to make a dense mark but not so much that the ink runs.
7. Carefully remove the jig by lifting it vertically, taking care not to smudge the marks.
8. When the ink is dry, inspect the dots to make sure they are:
• round, without any wicking or bleeding
• opaque and of an even density
Troubleshooting ink dots
• Irregular dots can be caused by:
• too much or too little ink
• grease or dirt on the specimen
• Smudged dots can be caused by:
• too much ink
• careless removal of the jig after marking
• touching the mark before the ink is dry
• Bleeding or wicking of the ink dots can be caused by:
• bleeding can occur when a specimen surface that has been prepared using an
abrasive causes the wet ink to be drawn, by capillary action, into the grooves
made by the abrasive.
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