The Glass Painter's Method

A challenge

It isn’t every day you sit in a tycoon’s boardroom (complete with a terrifying set of Gothic, lion-clawed chairs) and receive a challenge:

The commission is yours (the tycoon growled) if, within seven days, you can forge me a convincing piece of ancient-looking painted glass. It would be nice if it were beautiful, but above all else it must look old.

The boardroom was littered with other makers’ samples – wallpaper, curtains, rugs, table-tops etc.

I could see the tycoon’s problem.

The tycoon’s problem

And the problem was:

Everything looked new.

Beautiful but … new.

Indeed, money can buy most things.

But that’s precisely why it’s often nicer to make the impression that money bought these things a long, long time ago …

Anyway, we accepted the challenge. Why ever not?

1. Arouse curiosity

This was already an interesting aspect of the challenge: what exactly to depict?

There had to be a narrative, an imagined story – something to seize our client’s imagination and excite him.

David and I spent a dutiful morning, walking around various ancient English churches, until we came across a window in the corner of St. Laurence’s in Ludlow, and found The Adoration of the Magi.

We liked the look of Casper’s casket.

I took a photograph. David used it as a basis for this design:

So at last we’d found an image we believed would satisfy the tycoon.

And now I want to tell you how we made in stained glass, and also aged it.

2. Choose good and appropriate glass

The faces in a 19th century stained glass window may look white.

But, in your hand, and out of context, you’ll often find them to be green.

The reason is, their colour was purposefully chosen to hold its own against the strength of the bleaching sun.

Our tycoon is a lifelong collector of stained glass. He will therefore know this fact. So we found an interesting piece of tinted, mouth-blown English glass and cut it down to size:

3. Map out the main lines

This often means first laying down a smooth undercoat.

Then, with the glass on top of the design, you use a fine tracing brush to make a literal copy of the outline.

Note: it’s often easier to prepare a pencil tracing from the water-colour design, and work from this.

4. Initial highlights

There are so many different ways you could go forward from here. for example, it’s often possible and advantageous to build up shadows right away.

Here we settled on a more immediate approach, setting down some highlights straight away:

5. Giving body and weight to the image

It comes as a relief (because you thereby move away from a provisional state of affairs) when you strengthen and/or thicken your original trace lines, and block in around the edges of your glass, in order to contain the light:

This close-up draws your attention to the roughness of the blocking in.

The point is, perfection under a microscope can sometimes conflict with the wider and more important objectives, such as being legible from a distance, and also – crucially – gaining the tycoon’s confidence. Remember: he wants it to look old and wrecked by time.

6. Other appearance of ageing

Always remember the back of your glass.

It is your second canvas.

Working the back of the glass you can either add shadows and thus create a greater sense of depth.

Or, as here, with a light wash plus a good toothbrush, followed by some gentle rubbing, you can start to mimic the  ravages of age.

To be clear: these spots are on the back of the glass. With a suitable firing schedule, and a suitable mix of paint, you can fire both sides at once.

7. Authenticity

It is a modern luxury, and sometimes even an indulgence, to run the risk of firing your glass several times.

Yes, it’s easy when you have a computer wired up to your kiln, and you can walk off and get on with other things.

In earlier times, you’d pay a great deal of attention to the firing, and chance it as infrequently as possible.

So a lot more painting would go on between your firings.

In particular, you’d often resort to oil, as here, to build up further shadows:

With oil, you can give tremendous expression and delicacy to your shading.

8. Secondary highlights

Another wonderful quality of oil is how you can take your time to make exactly the highlights you want:

And you can also blend them afterwards.

9. Older still and older …

You can add texture to the front of the glass by flicking water onto the oil you applied earlier:

The effect is random, so you have to pray you get what you want:

10. First firing

Then a few hours while the kiln does its work:

Incidentally, without oil, you can reckon your lines and shadows will lose 10-15% of their density in the kiln. They get lighter.

But with oil, they don’t. The oil protects your water-based glass paint underneath. So firing doesn’t make your lines and shadows lighter, which is useful, because you know what your fired glass will look like. (There’s no guessing.)

11. Tracing and shading with silver stain

Time was when you’d have been anxious about staining – it’s such a messy and frustrating job with water or vinegar.

With oil, it’s so much easier (though you always have to run suitable tests):

More using oil to stain over here.

12. Second firing

If you’ve done your tests, there’s little cause for worry now.

Unless there’s a tycoon who wants his proof …

Did it work, the stain?

And was the tycoon pleased?

What do you think happened?