Larry,
I use Copic markers sold by oozak.com. They have a couple different kinds, and the ones that work best are the Copic "original". This type comes with what they call a standard fine nib, and you can also get super fine nibs to replace the standard. I keep two markers, one with the standard fine and the other a super fine nib in each of the three colors I have (dark bark, burnt sienna and cadmium red). Using these nibs it's not too hard to keep the dye where you want it. The bead and the burn lines help to contain the dye and prevent bleeding. There are places around here that sell Copic markers, but I've only seen one type, and that is the "Sketch" version which has a much broader tip and not good for this kind of work. Of course, there are those "screw-ups" on my part where a "slip" gets dye where I don't want it. That's when I scrape, or shave the wood till the "oops" is gone. If you haven't seen it, you should check out Jim Adkins excellent tutorial on sawmillcreek. Jim does a great job explaining the tools and process for making these basket illusion pieces.
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