Hands-on weathering pigments with Mr. Justin
While at Adepticon, I was able to take a number of classes. The first of which was a class on the use of weathering pigments. Now, like most painters, I've always painted on my weathering, like rust and maybe dabbled a bit in adding some medium to make mud. After this class, I picked up the entire set of Secret Weapon Miniatures (facebook) pigments. Let me tell you/show you why.
Weather pigments
Perhaps we should start with a bit of a primer on what exactly pigments are. We probably all have some experience with pigments be it from art history class or staring at women. Pigments are essentially chemical compounds that reflect certain wavelengths of light so that we see a specific color. These are found throughout nature in insects, rocks, and plants. Though the majority of painters purchase paint, a small community now still uses pigments to create paints. This was the standard in the past, before industrialization made paint purchase so easy and before the paint was so consistent. So what does all of this have to do with staring at women, well eye shadow and similar make-up is an incredibly fine pigment which is applied to the skin to create different tones.
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Pigment application
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The second area is in the corner which was a demonstration of ash. This is a two color process where Justin loaded the brush then tapped onto the base, alternating colors to create this instant ash look. This was a sort of bonus as we were just really working on the pipe and the bricks.
Of course like a dolt, I didn't capture a picture of the weathered bricks that he did. Now let's discuss what I was able to accomplish in about 15 minutes of work. The picture above (left) is the base blank that was primed with an airbrush using primer from Badger Airbrush. All other color on the base comes from the pigments as you can see on the plate. Justin recommends using at least three colors of pigment to build up to the desired look.
Additive method
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Now, I am sure you are asking about the mechanism to keep the pigment on the piece. To do this, there is a fixative material (fixer) which you will apply at the very end. This is easily applied by using a brush (not the same as you use to apply the pigment). Load the brush with some fixer, then just barely touch to where you need to fix the pigment. When the bristles barely touch, a capillary action will draw the fixer off and then gravity will let it settle. This will give you the appropriate amount of fixer without moving the pigment. The fixer will cure in 15-20 minutes.
Subtractive method
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Once you have achieve the overall look you want, you will then use a Q-tip (either wet or dry) or similar tool to remove the excess. You can do this by either rolling the Q-tip over or dabbing onto the surface until you get the overall look you want. These will provide different looks depending on how you remove. I use a small piece of paper towel to rub off the excess. After this was done, I went back and added a little trail using a lighter, mud color as one might see with scurrying rats. I think I should have been a little heavier on that.
You can also finish by adding some mortar with an appropriate colored pigment between the bricks. This could be done with a very fine brush and stippling between the cracks. Then fix as described above.
Thanks,
Chris