When you buy a kiln, you also need a shelf (or shelves if there are several levels in your kiln).

But you don’t fire your glass directly on this shelf.

• The shelf is not – repeat: not – non-stick.
• Nor is it smooth.
• Nor does it heat up and cool down / expand and contract at a similar rate to your glass.

All this defines your quest: you want a non-stick, smooth surface which expands and contracts with your glass.

There are different options here.

1. You can prime your shelf with kiln wash.
2. You can use ceramic fiber board.
3. Or fiber paper.
4. Or you can fill a metal tray with a powder such as whiting (calcium carbonate).

Now life’s too short to argue pros and cons with you.

Instead I want to jump to what we do and how we do it.

At Williams & Byrne, there are occasions when we use fiber board or fiber paper:

I was just about to say how board and paper don’t leave your glass particularly smooth beneath – and then I remembered how I’m not here to argue pros and cons with you.

Moving on then: mostly we use kiln trays.

Kiln trays filled with whiting:

Only wouldn’t you just know it, it’s a bit more complicated than that.

You see, we want the trays to last for many years, heating up and cooling down sometimes several times a day: we don’t want them to warp.

And so, rather than the kind of tray you’d carry food on, our trays have a hole in the middle:

This hole is excellent for getting a Dachshund to jump through but useless for serving food on.

The four sides are each made from L-profile mild steel, mitered at the ends and welded:

And now we fill the hole with fiber board which rests on the lip …

… where the whiting goes on top.

But you can’t just spoon it in and rest your glass on it.

You have to flatten it.

Really flatten it. Which makes is smooth. It also makes it firm. And it squeezes out trapped air.

Your fired glass will never stick.

It will also have the smoothest, silkiest surface you’ll ever run your finger across. OK, I exaggerate. But it’s really smooth, I promise you.

And here’s what we do to make it smooth.

Please just remember how kiln wash is fine.

Fiber board and fiber paper are also fine.

All I want to do is show you what we do here in case it’s ever useful.

And like I say in the video, it’s only every year or so you need to throw out the old whiting (it gets brittle, for want of a better word). Most of the time, your remove a bit here and there, sprinkle on a teaspoonful of whiting, then smooth it down with the roller. Very quick – very smooth and firm.

I hope that’s useful.