Proper Care of Marker Nibs
What to Avoid:
A good rule of thumb is: if it is a material that smears when it gets wet, stay away. If it must be colored over, use the Copic Airbrush System to apply the color, rather than making direct contact using the marker nib.
White Out or Opaque White:
Avoid coloring over white-out, even when dry. Aside from looking bad on paper, it will leave a white spot on the tip of the marker.
Bits of un-fired clay will clog the pores, leaving the marker tip discolored. Plaster may cause the same effect and should also be avoided. Clay coated papers should be tested, as some will work and others will not. Ceramic paint-it-yourself ornaments are fine. Sculpey, after it is baked, also works well. Glazed ceramics are generally okay, although the ink may build up on their slick surfaces.
Quick work or single strokes are generally fine, but trying to color over most acrylics will clog or discolor the marker nibs. If acrylics are used over original work, some dark marker colors may bleed through the layers of acrylic paint, so always test before adding acrylic to a finished piece.
Always use chalks or oil pastels after coloring with your markers, never before
Solvents or Oils:
Avoid coloring on top of solvents or oils. Many are okay to use over a marker drawing, but be sure to check the package to see if they contain alcohol, ethanol or something similar.
Avoiding Nib Discoloration
Copic markers are commonly used with watercolors, pastels, colored pencil or acrylics. However, these other mediums should be used AFTER the marker work has been done. Any other inks that are not given enough time to dry (but that usually work with Copics) will discolor the tips. Your pale colored markers will show the most damage .
If you color over a thick pencil line with your marker, quickly scribble onto some scratch paper to remove the residue from the tip. The same goes for colored pencils; while ink flow should not be affected, the tip will become discolored.
The paint is so thin that it usually won't cause a problem, but it may discolor the marker tips. If you are using watercolors, make sure to use them first, allowing the watercolor to dry completely before using the markers.
Colored Pencils/Watercolor Pencils:
Use these only AFTER the marker work is done, as they will discolor a marker tip even more than a graphite pencil. Quickly scribble onto scratch paper if any penciled areas are colored over.
Wet Pen Inks:
Even if an image is drawn with the proper inking pen, if the line is not totally dry there is a risk of staining the tip. Allow your inks to dry thoroughly, especially on non-porous papers like vellum, trace or mylar.