We get to hear a lot of questions about how to shade and matt stained glass. Here’s one from our regular postbag …

How to blend and shade

A loyal reader writes:

I’m finding it difficult to get a nice smooth shadow. If I try to get a subtle gradient shadow by taking off a little of the matting, then it usually ends up streakier than I want it to be. Either that, or I’m left with brush-marks in the paint … I am thinking that maybe it is because I have too much gum Arabic in the paint, since it seems difficult to remove sometimes.

Or it might be the brushes that I am using – and yet, if I try to use a softer brush, then I don’t remove anything at all!

May I ask your opinion of what my problem might be?

Now shading is difficult.

1. It’s sometimes difficult to decide exactly where the shadows should really be: that’s a question about design.
2. It’s sometimes difficult to put shadows where they should be.
3. There are many different ways of shading, and one must therefore decide which technique to use, and when. (I often find shading difficult; David far less so. But then, he’s been painting for 30 years; me, just 12.)

Regarding the question, if you’re using the technique of softened lines that we present in Part 1 of Glass Painting Techniques & Secrets from an English Stained Glass Studio, then we’d definitely consider that there might be too much gum Arabic in your paint.

But it’s also possible that there’s something to learn about the specific technique we teach – in particular about how to use a blender.

So let’s re-create the scenario.

1. You paint a light dry undercoat.
2. You copy-trace the lines that you wish to transform into shadows.
3. You reinforce these lines.
4. You paint an overcoat.
5. You take your blender and, while the overcoat is still wet, you soften the traced lines and change them into shadows.

If the lines from steps (2) and (3) are too dark and/or contain too much gum Arabic, it will be difficult to soften them.

If the overcoat from step (4) is too dry, it will not sufficiently dissolve the lines for you to be able to soften them.

And say the lines and the overcoat are “just right”, it is still necessary to use the blender decisively and at the correct speed and with the correct heaviness/lightness in order to soften the lines successfully.

Certainly, the more you use this technique, the easier it gets.

It’s really worthwhile doing it time and again on the light box (not on a “real” bit of glass), just so that you get really relaxed and confident about it.

Note: of course there are other ways of shading. It’s just that this technique is particularly useful – yet little known.

It’s all in this here downloadable stained glass painting manual – free chapter here.

And then we’re also here to answer your questions and help as best we can.