Hello Alex,
Thank you for your very kind assessment of my work.
At the bottom of this post are some pictures of the ink I have been using but I'll add some explanation first.
For the red I used a watercolor ink. Watercolor ink doesn't have a lot of pigment, and this is what I wanted (I wanted to show the wood grain and treenails under the color). In this case I used two coats to give a more uniform red color - no primer - and I used brushes (ink doesn't have a brushstroke problem anyway).
For the blue I used two coats of a waterbased acrylic ink. Acrylic ink has much more pigment in it than watercolor ink. Again, this is what I wanted (I didn't like my tests with a transparent blue). Because I was adding swirlies over the top of it, everything looked cleaner on a more opaque background. It you wanted to show more wood grain then either use a watercolor ink or only one coat of acrylic ink.
The blue was a bit too bright, so I knocked it down with the Cyan blue watercolor ink shown below - very little ink on the brush almost like drybrushing...
You didn't ask about the black but here I wanted total opaqueness. To accomplish that I used a waterproof India Ink (like for a quill pen). This has more pigment than an ordinary ink.
Warning: you cannot paint waterbased paints (my swirlies are done in Vallejo acrylics) over the top of waterbased inks. The top color blends with the base color rather than sitting on top of it (I guess that could be a cool effect if you were going for that but I wasn't). You have to seal the undercoat. I used wipe on poly.
What I have shown are cheap and ordinary art supplies. Several of our international friends use Schmincke watercolors the same way I have used these. I wasn't able to source Schmincke here in the US without buying their full range of colors (or a sampler). You can find what I used at Michael's Craft Stores here in the US and still have money left over for lunch.
Hope this helps and I'll be happy to answer any other questions you might have.
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