How To: Chalk Pastel and Watercolor Pencil for Models

I received a Frame Arms Girl Magatsuki Kikka as a gift, so decided to use her as a demonstration of how you can get some really wonderful shading and effects without using an airbrush - or any sort of paint at all.

One of the bonuses of this method is that it's completely non-destructive and non-staining. If you don't like how it turned off you can completely strip a piece - even white ones - back to bare plastic with just some soap, water, and, if needed, a soft bristle toothbrush.

You can also use it over a painted base, so if you lack an airbrush setup you can use a spray can to create a base layer and apply these techniques over that. Or just use it for general finessing in combination with other painting techniques. Different paints will vary in how well they receive the pigments, so consider top-coating your base or using practice spoons before diving in.

And while I don't discuss it here, it's excellent for creating blast and char effects as well as simulating various types of age, grime, and dust.

Tools used in this guide:

Chalk pastels

Watercolor Pencils

Hobby Knife

Soft Bristle Brushes

Melamine Sponge

Water (optional)

Liner brush (optional)

Top Coat/Sealant (optional)

These are Mungyo Brand chalk pastels. I bought them for $7 on Amazon. Don't worry too much about what you pick - their quality as actual chalk pastels doesn't matter. Just get something cheap and heavily pigmented.

Similarly, these watercolor pencils were just what I happened to have on hand. I've had them since I was a kid.

Watercolor pencils are very popular with doll artists for doing "faceup" - recoloring/painting the faces - which was part of the inspiration for using this technique on my girl model.

Watercolor pencils can be used dry to draw directly on the surface of the kit, or you can very lightly dampen the tips to leave heavier marks of pigment. And if you wet the color while it's on the piece, you can get effects similar to a wash.

I don't have any pictures of the brushes I used (honestly they weren't even the ideal ones for this purpose) but you want to use something that resembles a small powder brush, like for the application of face makeup. You can probably purchase a cheap small blending or eyeshadow brush at your local dollar store. Silicone brushes could also theoretically be used for some effects, but I didn't try it during this run.

If you plan to use wash-like techniques, a thinner standard brush is needed as well. Whatever you might normally use for panel washes - I like using long, thin, script liner brushes.

The hobby knife of course is required for building the model, but was also the primary tool I used for turning the chalk pastel into the form I actually wanted it in - powder. If you slide the back of the knife along the corner or one end of the pastel it will give you a lovely pile of soft powder to use in your projects. You can make jars of this, or use it little by little for the convenience of having a full stick (less messy, no tiny jars floating around, pre-made storage).

Melamine sponges are literally one side of a Mr. Clean Magic Eraser. But DO NOT go out and buy a ton of Mr. Clean Magic Erasers. You can get 8 of those on Amazon for $15, or literally 50 plain melamine sponges for the same price. Melamine sponges are incredibly useful for model building - they are basically a very mild abrasive surface, which is why they are used as cleaning products.

You can also use melamine sponges to clean up panel lines and to create a matte look on bare plastic without needing a top coat - it does get very dusty though! Consider picking up a duster, rocket air blaster, can of air, or similar tool.

This process is not very kind to the sponges, however. I basically used an entire one just on this kit.

Now that we have all that covered, let's begin, shall we?

Step one was cleaning and assembling. Not much to say about this part. If you need help with this section, that's a topic for a different guide. Or message me on Discord! I'd be glad to help out.

Cute! Her face comes prepainted, though the treatment on her smile makes her look... well... a bit derpy. It's not as obvious in this photo, but trust me on that one.

Don't worry, we'll work on it.

There's also some face decals included if you want to work from the ground up, but I won't be addressing that in this guide.

With her armor on, and one of her other faces. I'm mostly sharing this to give an idea of what she looked like before I did any work on her.

First thing I did was work into her face. I chose her generic smiley face and made some alterations to create added depth and sense of life. Her bangs hang over most of her face, so I added plenty of shadowy tone (it still ended up not being enough, either).

Note: all of the process documentation photos were taken with my cellphone and do a bad job of capturing subtleties in color. My apologies!

I mostly used these two colors for the shadows of her skin across the kit. I also used a rich umber watercolor pencil. I shaded her forehead pretty heavily, as well as the side and temples, and added depth under her eyebrows and in the inner corners of her eyes. I used a soft pink shade to extend a blush tone across her nose and added some shading underneath it to imply added depth. For her mouth I used a salmon and a pink pencil to gently alter the shape and color, artificially widening it and making it look more naturalistic. Someone compared it to lipstick, which I guess I'm also okay with.

I tried to make a comparison image of a shaded hair piece (right) and unshaded (left) and my phone completely failed me. Red are especially poorly handled, unfortunately.

For her hair I started with a rich, dark magenta watercolor pencil. I wet the tip (just a little!) and used it to loosely apply color to some of the deeper grooves. I then used a thin brush and water to wet the pigment, allowing is to sink into the forms like a wash.

Remember, in this case it's almost universally better to work damp and not wet. This should be a fairly dry process.

After the "wash" had settled I took a mix of pink, purple, and magenta powders to brush in shading and generate depth.

You can probably see the shading in her hair most clearly on the ponytail in this image.

The headpiece there was done in pretty much the same manner as I would end up doing the entire kit. This was before the piece was cleaned up with the excess powder removed.

I used a blend of these three blues and a soft brush to apply a blush of color where shadow would exist on the piece - clipping the brush on the edge of a harsh line would often fill it with a crisp dark panel line, but I would also use a deep blue watercolor pencil and water to further accentuate the line - picking up some color onto a thin brush and just running it along where it was needed.

I met with no issues by mixing the pigments, and in fact did so for every color on the kit. It always came across as one cohesive blended color.

After a bit of experimenting I found I got really solid results applying the pigment and then simply smudging it out with my fingers or a paper towel to create a blended even tone.

Once the pigment has been applied it can be left as is - if you are hoping for a grungy gunk-wash type effect - or, as is more likely, you can choose to remove the excess. You can do this with some paper towels, or, what I found to be most successful, that handy dandy melamine sponge I mentioned before.

Just don't push too hard, or dig into the grooves. It's completely unnecessary and will just undo all the work you put into adding color in the first place. 

!Note! During clean up make sure you hold the piece using a clean paper towel or cloth and not your hands - no matter how hard you try, you WILL get powder on your hands and it WILL transfer to the piece and smudge it all up everywhere. Even if you wash your hands. Just do it.

And if you do mess up, well, at least the pastels are cheap, right?

Nor should you be afraid to really go for it. Because the pigment is so gentle there is no need to be especially cautious about your application. In fact, I frequently found that overfilling the piece was the best bet to guarantee coverage and filling in all the nooks and crannies.

You can see above the heavier spots in the deepest grooves where I liberally shlopped in the watercolor as well.

A small warning though - if you get your piece completely coated like the one on left a few papertowels might not be enough to remove the tint and you will most likely have to resort to the melamine sponge to return it to it's natural color.

Here's a piece before using the melamine sponge, just wiping it down with papertowels only. You can definitely see the strong blue tint.

Her two legs, one treated, the other not. One thing to note - without putty/primer/paint the seamlines become extremely visible as they are eager to trap powder and washes without efforts made to prevent it. This will be more egregious on older kits when less concern was made over seamline and nib placement.

Kotobukiya, the manufacturer for this kit, also uses a plastic injection process that is more prone to discolored nib marks. This of course can't be hidden without paint. Bandai (Gundam) kits are less prone to this issue for whatever reason. It's not an issue inherent with this method or anything like that.

Her midsection (I cleaned the white pieces afterwards, don't worry). This is probably THE BEST example of what pigments are capable of. They are incredibly useful on skin and other "soft" or rounded surfaces.

She didn't have many areas where it was applicable, but red tones can also be added to cheeks, ears, fingers, elbows, and knees. If you want you can even use real blush. Why not?

I'll post some more shots but the process remained about the same throughout.

The comparison is most noticeable when you compare worked to unworked sections.

The gold pieces were lined in dark brown and the smallest touch of black (I think I touched them up more after I took this as well). Her black pieces also received black but it really isn't visible. If I wanted I could add white highlights using a dry white watercolor pencil or white paint but I didn't do that here.

I also added a fair bit of shading where the shoulder joint is, but it's easy to miss. A lot of things aren't obvious, but would stand out if they weren't done. Maybe no one notice, but they'd feel it.

The tissue paper was to trick my cellphone into seeing the tones correctly.

Her ribbons all turned out very nicely. 

Areas that were covered by other pieces I tried to shadow more heavily, such as the pieces under her leg layers and the underside of her chest piece. I perhaps didn't do enough on the backsides of shadowed pieces, like her lower leg and arm shields, but that's largely nitpicking.

The swords turned out really well for something you barely see when full assembled. The black just rubbed right off the glossy plastic, no melamine needed.

All finished!

You did well, faithful sponge.

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