Weathering with art supplies part 2, more oils

Following part one in my weathering with art supplies, I continue with more uses for oil paints. In part 2, I'll cover streaking effects, dusting, and fading/shading.

A note on layering

Before I get into more techniques, I'd like to mention that I am a proponent of the principle of layering. If you've read Mike Rinaldi's Tank Art books, you are already familiar with the concept. Before I start weathering, I remind myself not to try to do all the weathering in one go. If I were to try to do it in one go, I end up over-weathering the model when I add subsequent layers. I add a little weathering at a time, then sit back and ask myself if it needs more. For example, I add a few subtle streaks here and there, or a thin layer of dusting. I'll let the oil paint dry for 24 hours. During this time, I can look at the model from a distance and assess my progress. If I want more streaks or dust, I'll add another layer, usually with a slightly different shade of the previous color. The drying time means that adding the next letter won't obliterate the previous layer, and the slight color change adds depth and variety (note that I said "variety" an d not "contrast," which is a different concept).

Streaking Effects

As with filters and washes, streaking effects can be achieved with artist oil paints. Different colors can be used for different streaking effects. I use burnt sienna for rust streaks, Naples yellow mixed with burnt umber for dust streaks or rain marks. Whatever the color, the techniques are the same. I use two main streaking techniques: subtle streaks and large streaks.

I thin the paint about 50/50 with odorless thinner (give or take 10%). Sometimes I add a bit of Winsor & Newton Drying Poppy Oil, just a small brushfull. This adds a slight amount of transparency and it changes the consistency of the paint--the paint feels more slippery and it brushes smoother. You can add more poppy oil if you want a bit of sheen on your streaks; this is handy for fresh fuel streaks, for example. I choose the poppy oil because it dries faster and doesn't increase gloss very much. But you can use any oil medium you prefer.

For subtle streaks, I start by applying a few short vertical strokes or small dots to the model. I then blend the paint downward with a flat brush, creating the streak. The key to getting this right lies in the amount of thinner on the blending brush. Too dry and the paint won't blend, too wet and you end up wiping away the paint. I like to keep the brush 99% dry. I dunk the brush in odorless thinner, then blot away most of the thinner on a lint-free cloth or coffee filter. This only gets the brush 75% dry, so I keep doing it until it's dry enough. Basically, if I can see wetness when I blend the paint, it's too wet.

I'll blend the paint downward until barely any paint remains. I'll then shoot it with a hair dryer to speed the evaporation of the thinner. At that point, I move on to the next section. (I usually work in small sections at a time). I allow the paint 24 hours to dry before I apply more weathering or another layer of streaking. It may not need a full 24 hours, but I've tried after only 12 hours and I found that insufficient. So the ideal drying time is somewhere between 12 and 24 hours.

Here is a quick example of what a single layer of subtle streaking looks like.

For large streaks, I like to work on them one streak at a time rather than a whole section at once. This allows me to have more control over the final result. I start by brushing a longer, but still narrow, vertical stroke on the model. I'll blend the streak as usual, but because the streak is longer, it tends to widen itself as I blend it. It usually widens too much for my taste. Fortunately, the fix for this is simple, but it's not obvious. I wipe away the excess width with a round brush that is wet with thinner (not dripping wet, but wetter then my blending brush.) The trick to this is in how you hold the brush. Instead of holding the brush nearly vertical to the surface like I normally would, I hold it nearly parallel to the surface of the model. I then wipe away excess paint. For some reason, holding the brush this way gives superior control over my normal method. I don't have an explanation as to why that is, but credit for it goes to Mig Jiminez.

As with subtle streaking, I will zap the wet paint with a hair dryer and move on to the next streak. And as before, I let the paint dry for 24 hours and decide if it needs more layers. I like to do the big streaks in several layers. The first layer will be the longest and thinnest. Each successive layer is applied shorter and narrower than the previous layer, also with a subtly darker color.

Dry Painting

I call this next technique "dry painting," but it is very similar to "dry brushing." The difference isn't just in the name. Traditional dry-brushing is used to highlight raised detail, and I consider it a basic technique and won't cover it here. Dry painting is a similar technique, but instead of focusing on raised detail, I used it on broad, flat surfaces to add variety. Not that you can't do traditional dry-brushing with oil paints: you certainly can. But dry painting can achieve many different effects, such as shading, fading, dusting, and more.

I got the idea for dry painting from Mike Rinaldi's Tank Art Vol 2. In it, Mike describes using enamel paints to add variety to broad surfaces using an almost dry brush. When I first read about the technique, I wondered if it would work with oil paints. I don't use enamel paints, so I didn't want to take up paint shelf space by cluttering it with more bottles. I decided to try it with what I already had: oil paint. If you have enamels and want to use them for this technique, go for it! You won't offend me.

Dry painting has many uses. You can use it slightly lighten or darken the base color, adding visual variety (note I didn't say "contrast," which is a different concept). For instance, you might slightly lighten the base color to represent faded paint on upper surfaces. Or darken the base color to represent shadow. (In theory, you could use this technique to duplicate the color modulation/zenithal light technique. But that's probably easier to do with an airbrush). Or, you could use a dust color to add a thin layer of dust or dirt to a surface. You could do the same with a rust color. You can even use an off-white color to enhance a whitewash. This technique excels at adding exhaust stains or gunpowder stains. The possibilities are almost endless. You can use dry painting as a substitute for a thin layer of pigment powder or pastel dust. The oil paint has an advantage over pigment powder: it has its own binder and will therefore stick to the model without the need for a fixative.

Like all techniques, this one takes a bit of practice, but not much. If you've done traditional dry-brushing, you have a head start. Using a flat brush with soft bristles, load the paint brush with your color of choice (unthinned). Then wipe most of the paint off on a paper towel or coffee filter. Wipe the brush until it no longer leaves paint behind, then wipe it some more. Until you get the hang of it, it is better to have too little paint than too much. But with slow-drying oils and enamels, you can always wipe away excess paint with a clean brush dipped in thinner.

Once the brush is mostly dry, gently and slowly brush the paint onto the surface. When I say gently, I mean with as little pressure as humanly possible. I like to use just the tip of the bristles and hold the brush perpendicular to the model surface. This should leave behind an amount of paint that is barely noticeable. If you don't see any paint on the model, slowly increase the pressure until you do. Be careful, it's easy to add too much. I always stroke the brush vertically or with the direction of airflow.

As you continue brushing, you will leave less and less paint behind until you need t reload your brush. I take advantage of this feature to soften the edges of the area I'm painting. I'll start brushing where I want the most paint, then I'll move to the edges as the brush gets drier. This creates a gradation of color instead of a hard edge. If I need to blend the edges more, I use the same technique with a clean brush barely wet with thinner.

Here is a basic, slightly exaggerated example. On the left I used Sap Green lightened with Naples Yellow. On the right, I darkened the Sap Green with black.

 As another example of dry painting, I added exhaust streaks to my 1/48 Spitfire Mk IX. I originally tried to add the stains using pastel dust, but I couldn't get them to stick despite several layers of varnish. With the oil paint streaks, I don't need a varnish and the streaks will be durable.

 That concludes my oil paint techniques. As you can see, the versatility of oil paint is practically endless. In the next installment, I will show you how I use art supplies to create thick mud.

Part One