Conservation: the Glass Painter’s Nightmare

The Real Glass Painting podcast: episode #3

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So today is Friday February 14th 2014, and our topic for today is conservation – the stained glass painter’s nightmare.

OK, it’s been a while since we last talked but be assured – what my podcasts lack in regularity they certainly make up for in … horror.

You have been warned.

Backstory – this is important … later

We’ll start by stepping back through time to the final cataclysmic years of the 20th century when, gentle listener, I had a fascinating job in the City of London – yes, that square and oh so very English mile of bowler hats, tightly rolled umbrellas, pin-striped suits with mauve silk lining, loud braces, Purdey shotguns, sharp ties – and sometimes even sharper business practices.

Now some people knock ‘finance’ – and sometimes it needs knocking – but I had a good, hard-working time, and got to know a bunch of brilliant people.

See, I was a business analyst, a trouble shooter.

So I went round this vast company I worked for – and fixed problems.

Business problems.

And – back then, in the tail-end of the last century – the company had just spent £4 million and the last 3 years developing a computer system.

A computer system – which didn’t work.

Oh it was accurate. It held the data perfectly.

And it was complete. Everything was there. Everything.

So can you imagine what the problem was?

The problem was, you couldn’t use it. You couldn’t get the information out.

So I went to the M.D. and I said,

The £4 million pound system doesn’t work. Give me £100,000 and I’ll sort things out for you.

He said yes and so that’s what I did.

I rolled up my sleeves, bought some software, bought some computing power of my own, learned a lot of code, and I wrote a tool which hacked into this monstrous binary gulag and got things out.

Not just that. This tool I wrote – this ‘app’ before the word was even coined – it got things out in any shape or form you wanted.

So the underwriters, the insurers, my masters, the people who paid my salary: they could actually ask whatever questions they wanted. Anything at all. If the information was there, my tool would get it for them and they could have the answer quicker than the time it took for the office boy to buff their shoes.

It took me 6 months to write.

A triumph. I’d saved £4 million pounds. People could now get on with their work … A triumph, yes?

Except it wasn’t.


Two years later, my system wasn’t there.

It wasn’t there.

Everything had moved on. Software, hardware – all gone, all changed.

Two years later, my system wasn’t there.

Nor was I.

I was so fed up – sick in my heart – of making things which didn’t last, of learning things which didn’t matter, I’d quit.

So I’d packed in a good career in London EC3 and ended up in Smethwick, Birmingham, England – as down-trodden and depressing a region of the world as you will ever see – doing what became a 4-year apprenticeship under David.

The studio where I did this, the studio where we worked? Hardman’s. The John Hardman Studios.

This is the Hardman who carried out so many of Pugin’s stained glass commissions.

The same Hardman who made those gorgeous windows you find all over the world from the Houses of Parliament in London to St. John the Divine in New York.

Those windows which, unlike my fabulous 20th century computer system, are still here.

And these ancient stained glass windows are part of the reason I’m talking with you today.

The subject of our talk: conservation – the glass painter’s nightmare.

The structure of this podcast

The talk is brief – just the time it takes to tell you four good projects from our casebook.

Four projects. True ones.

Projects #1 and #2 are conservation projects. The main tools and methods a stained glass conservator uses.

But the third project has nothing to do with conservation. Nothing at all. For the simple reason it illustrates where conservation fails. Yes, conservation fails.

And my point is it’s good to remember that conservation has its limits, and where those limits are …

It’s good because if you’re interested in stained glass painting, you need to know that conservation itself won’t keep the practical skills alive.

Shocking but true.

Which brings us to the fourth project. A trans-Atlantic tale of excess and debauchery. It’s the reason for the title – “Conservation: a glass painter’s nightmare”.

Except – the title’s wrong.

These things happen, so I trust you don’t feel you’ve gathered round me under false pretences. “Conservation: a glass painter’s nightmare” is all wrong. It’s wrong. The title should have been: “Conservation: a glass painter’s worst nightmare”.

Which is the 4th story from our casebook.

Anyway, that thrilling, shocking, horrific story is about 12 minutes away.

So let me get things rolling straightaway and tell you our first story.

This first story’s called …

The Italian Job

OK, so we have a client who is as rich as Croesus.

A tycoon of vast and unimaginable wealth.

And, like all immensely powerful men, when his wife told him their old curtains were looking tatty – this was in the entrance to their ornate villa on the hillside outside Florence, Italy – he climbed up on a chair and hung the new ones there himself.

Unfortunately, he slipped.

And fell …

And his elbow struck a passing blow against the window, which wouldn’t normally matter.

But this wasn’t an ordinary window his elbow banged.


This was an 18th century stained glass masterpiece – some 6 feet high by 4 across.

Gorgeous. Intricate. Fantastically lit up by the bright Italian sunshine.

But broken …

Happily, the damage was slight.

The tycoon, cursing badly, just cracked the corner of a single pane.

A single, simple crack: the conservator’s solution makes perfect sense.

The conservator’s solution is, just hide the break with lead, then seal the crack with putty.

You hide the break.

And seal the crack.

Hide and seal: that’s it.

The main concern here, you see, is to stop more damage.

Yes, however decorative a window is – and this tycoon’s window was certainly a beautiful piece of decoration – it also serves an architectural function: it lets in light, whilst blocking out the wind and rain.

Rain – even Italian rain – can seep through a crack, run down inside, and thus wreck the paint.

And wind will easily buckle a window, which can cause further breaks.

So what the conservator must do here is make sure the window remains strong against the elements.

And in a simple case like this, the conservator’s life is very easy.

What David did was, he flew to Pisa.

Once chauffeured to the villa, he removed the broken panel, hid the break with lead then sealed it up with putty, put the panel back again, and took the next flight home: Italian job done.

The window looked fine again. Absolutely fine.

Just one thing he couldn’t mend … The tycoon’s pride.

How we saved Saint Peter

Of course, the conservator’s life isn’t everywhere so simple.

You see, wind can do far more than huff and puff and buckle a window.

It can actually pick up stones and hurl them with considerable force and break your glass to pieces.

This once happened close to us at Prinknash Abbey in Gloucestershire.

On this occasion it was Saint Peter who suffered damage.

Yes, Saint Peter’s head was cracked apart by wind-tossed tiles.

But you know what Benedictine monks are like?

So scrupulous in their practice …

They’d collected all the pieces!

All 12 of them.

Now, with this extent of damage, it would still be possible to re-join the fragments using lead.

But the effect would certainly be unfortunate – especially with a face.

It is not just the architectural function you must consider here.


A stained glass window also has an aesthetic function. You want it to look lovely.

I’m sure you’ve all seen ancient windows criss-crossed with lead in unexpected ways.

Many such leads are unlikely to be original – they are probably repairs.

We might learn to live with these repairs.

But there is a limit to the disruption our eyes find beautiful, and soon – the window becomes unreadable.

‘Hide and seal’ becomes too ugly.

Thankfully, from the about 1960s onwards, lead wasn’t the only conservation option.

There was also glue. Clear, transparent glue. So nowhere as obtrusive as lead.

So the process is, you clean the pieces carefully, then glue them one by one, using wax to hold them steady until the glue has set next day.

Which is exactly what I did for Peter.

So there weren’t those tell-tale and intrusive black lines which you get from lead.

All the same, you must not think the joins could not be seen.

On the contrary.

Anyone who looked could see Saint Peter had been the victim of a serious accident.

But it wasn’t so much the glue which left a trace …

It was the glass itself.

… Or rather, the glass – which wasn’t there.

You see, as well as those 12 fragments, there’d been many splinters …

Splinters which the wind had scattered far and wide and lost forever.

This always gives a problem for stained glass.

The reason is, unlike other media, a stained glass window relies on transmitted light.

That’s how it works.

Transmitted light.

And a missing splinter will distort the light’s transmission as surely as a scratched CD distorts the music.

So Saint Peter glittered in ways he wasn’t meant to: each missing sliver, however small, was visible by its absence.

A very good repair. But very visible all the same …

Here then is the choice the conservator must make …

Glued glass will attract attention because the transmitted light is broken up by the missing splinters.

But lead – and copper foil – will only pass unnoticed in small quantities, and soon become obtrusive.

You see the problem here?

It is in the very nature of stained glass conservation that its repairs are always – in some measure – visible.

Yes, conservation was fine for The Italian Job and more than good enough for Saint Peter of Prinknash Abbey.

But conservation isn’t always fine.

Sometimes it’s just not good enough.

Which is why I mentioned in the introduction that stained glass conservation is so limiting.

That conservation – conservation itself – does very little to keep alive the skills of stained glass painting.

Take the tragic incident at Belmont Hall

The owner called the builder in to fix the guttering around their lovely home.

There was lush ivy growing everywhere.

And you know what had to happen, don’t you?

A builder was almost honour-bound to rest his ladder where he shouldn’t.

And then, believing it was stable, he started his ascent.

His partner held the ladder, but he could not keep steady, and it slipped.

After a brief, explosive crack, there ensued that awful silence which you only ever hear when things are very … badly … wrong.

Careful investigation revealed how the ivy hid a landing window which housed the family’s stained glass coat of arms.

Painted, enamelled and stained on a single piece of antique, mouth-blown glass, measuring some two feet across: a vast, impressive, much-loved, ancient piece … it was.

All that remained was … a pile of brightly coloured glass.

We found 847 pieces – I counted them.

Now in a case like this, there isn’t much the conservator can do.

You see it’s obviously beyond the scope of lead. Imagine the result: nothing visible … all webbed and black. That wouldn’t do at all.

And just as clearly it’s beyond the practical scope of glue: with all the missing shards and slivers, how would anyone ever enjoy the glass again?

The whole point of conservation is to save the remaining window from further damage.

The remaining window …

And nothing has prepared the conservator for the situation where the whole glass itself is beyond repair.

847 fragments – quite beyond glue, utterly beyond lead or even copper foil.

So what did we do here?


David restored it.

He redrew the design, then copied the fragments and made a forgery of the original.

A perfect copy.

A copy so good you’d never know the builder’s ladder had ever slipped.

But that’s restoration.

Restoration. Not conservation.

And it’s restoration – restoration, not conservation, which can teach you how to paint stained glass.

How to paint in any style.

Conservation, on the other hand: conservation shows you how to hide the cracks with lead or copper foil, or bond them using glue …

Stained glass conservation … and stained glass restoration: two very different things.

And there is a serious problem here.

Say ‘stained glass’ to people – and ancient, broken windows is often what they think of.

… Broken and barely held together by lead …

Conserved stained glass – especially in a church – is most people’s primary reference.

It’s what “stained glass” means to them.

And this is something which exerts a baleful, debilitating and resource-consuming influence on the active craft.

Which brings me to the final tale today.

Conservation: the glass painter’s worst nightmare.

Yes, you see we have another client who is rich as Croesus …

This one lives in – Hollywood.

But don’t dismiss her just on that account: she’s written many famous TV series, and she also has the good sense to listen to her designer and come to Stanton Lacy for her glass.

She wanted a set of 8 stained glass skylights for her dining room.

I can’t say much because I know you’ll understand her privacy must be respected.

But what I can say is, this being Hollywood, she chose the sins and virtues for her theme.

That, and a vast bestiary: all writhing, slithering monsters …

So David designed these skylights for her, each one measuring a good yard across.

Big things.

Quite terrifying too.

Beautiful … but terrifying.

As source material, I had a facsimile of the ancient Flemish Apocalypse – a medieval manuscript with illuminated pictures – which you can imagine was very, very useful.

Do you see where this tale is going?

You see our client insisted – she was paying: it was her right – on medieval precedents.

Ancient-looking glass.

Nothing new …

she said.

Nothing new indeed!

A medieval paradigm – that’s what she’d set her heart on …

But not just that.

What I must tell you now is far, far worse …

You see, it took us 6 months to trace and shade and silver stain these massive skylights.

6 months.

Yes, 6 months of our lives.

And then – our client was paying: it was her right – then, so she could make it seem she’d bought these skylights from a New York auction house … she had us smash them with a hammer …

Naturally, she also paid to have us mend them.

Indeed, we used lead and glue and copper foil to do a perfect piece of conservation.

But to have to smash your work and then conserve it: that, certainly, is a glass painter’s worst nightmare.

And yet … and yet … this does not bring an end to my disturbance.

No end.

For return now to my ‘app’ – my parting gift to hard-nosed finance, the one I wrote before I quit the keyboard for the unambiguously sensual delights of sable tracing brushes – my app: it lasted – two … whole … years.

So actually when you think about it, my code lived far longer than our gorgeous – terrifying – stained glass skylights.

As the tyrant Ozymandius proclaimed: ‘Look on my works, ye mighty – and despair …’

A nightmare indeed.

Thank you.

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