Glazing · Bubble glaze with dish soap

Soap, a straw and a cup of glaze.

Blow the bubbles over the pot and let them pop where they land. Every bubble leaves a ring, and a few layers of dark rings over a light base is a surface no brush can make. It is a cup, a straw with a hole in it, and a tray under the pot.

Four steps with a tick list at each: the base coat and the straw, the cup, the foam, and finishing. Six fixes, most of them about the foam, and five videos from four potters.

This is the short version: the base coat, the hole in the straw, the cup, the foam, each with a tick list. The color notes, the glaze-versus-underglaze reasoning and the questions are in the comprehensive version.

1:1Glaze to water, plus more soap than feels right
HoleIn the straw, near the top, so glaze is hard to pull up
x5Videos, from potters who have nothing to do with us
x4Steps, each with a tick list you can work off
Jump to a section
Why this page has words and video The whole idea in three lines The technique in six moves What you need at the table 1. Base coat, foot, straw 2. The cup 3. The foam 4. Finishing and cleanup Four potters, five cups The one video to watch When it goes wrong How it works at The Clay Hole Questions people actually ask Related lessons
Illustration of a potter blowing through a straw into a clear cup of blue glaze, the foam heaping over a textured bowl on a banding wheel

Every step, the color notes, the reasoning and five videos.

Read it, then watch it

Why this is written down and filmed, both.

Bubble glaze is a recipe and a mess. The recipe is a ratio and a rule about the straw, and those go on a page. The mess is foam rising out of a cup and spilling over a pot, and how fast that happens and how it lands is something you watch once and then know. The videos are for the foam; the page is for the ratio, the hole in the straw and the tray under the pot.

Use both, in this order

Read the recipe and cut the hole in the straw. Watch the foam. Do it on a tile before a pot, at the far end of the table, with the tick list open.

The whole idea

Soap, a straw and a cup of glaze. Blow, spill, let them pop.

About half glaze or underglaze and half water, the cup no more than half full, a good squirt of dish soap, a straw with a hole cut near the top. Blow slowly until the foam rises, spill it over a base-coated pot, let the bubbles pop where they land. Underglaze bubbles go on raw clay, get bisque fired, then one thin clear. Tray under the pot, wiped down wet.

The five-minute version

The whole technique in six moves.

If you already glaze and you just want the shape of it, this is the shape of it. Everything below is these six moves, slowed down and with the places they fail marked.

1Base coat first, driedThree coats of a light glaze, dried. For underglaze bubbles the pot stays raw clay, because underglaze goes on before the bisque firing. The rings need something to show against.
2Cut a hole in the strawNear the top, just below your lips. Air goes out, and far less can come up. Never a straw without one.
3Half glaze, half water, a squirt of soapIn your own cup, from a little poured out of the jar. Stir until it foams. More soap than feels right.
4Blow slowly until the foam spillsOver the pot, on a tray, on a banding wheel. Let it fall; do not pour it.
5Let them pop, then layerHold the pot level. Two or three layers, each dried, for depth. Bubbles are the top layer, or under one thin clear.
6Wax the foot, wipe down wetFoam runs. The tray, the table and the wheel wiped before you leave. Cup in the bin.

Before you blow anything

What you need at the table.

Six things, and the straw with the hole is not optional. The tray is what keeps the mess yours.

A cup you can throw awayA paper or plastic cup, half full. Never a shared jar and never a brush that has been in soap.
A straw with a hole in itCut a small slit near the top before anything else. The hole makes it much harder to pull glaze up the straw, and you still only ever blow out.
Dish soapOrdinary dish soap. A good squirt; it burns out in the kiln.
Glaze or underglaze, darkA black, a dark blue or an iron brown from the wall, poured out into your cup. Underglaze bubbles hold the rings best, but they are decoration, so ask a main instructor before covering a whole pot with them.
A base-coated pot on a trayThree coats of a light glaze, dried, or a raw clay pot for underglaze bubbles. On a tray, on a banding wheel, at the far end of the table.
Wax on the foot, and a spongeFoam runs down. A waxed foot sheds it. The sponge is for the table and the wheel afterwards.

A throwaway cup, a straw with a hole near the top, dish soap, a dark glaze or underglaze, a base-coated pot on a tray, wax on the foot, a sponge.

1

Step one

Base coat the pot, wax the foot, cut the hole in the straw.

The rings need something to show against. A bubble leaves a ring the thickness of its skin. So: three coats of a light glaze, dried matte, and dark bubbles over it. Or raw clay with dark underglaze bubbles, bisque fired, and a thin clear over the top, which holds the rings best.

Wax the foot and let it go matte, because foam runs. Then the straw: cut a small slit near the top, just below where your lips go. Air blows out through the straw as normal, and the hole makes it much harder to pull glaze up it. Plenty of people who skipped the hole have had a mouthful of glaze, and the hole is there so it does not happen to you.

Set up at the far end of the glaze table with a tray under the pot and the pot on a banding wheel, so the foam has somewhere to land and the pot can be turned under it. Bubble glaze is the messiest thing on the glaze wall by a distance, and a tray is what keeps it yours.

Tick list, setup0 of 4
2

Step two

Mix the cup: half glaze, half water, more soap than feels right.

Your own cup, from a little poured out of the jar. Never a straw near a jar. A few spoonfuls of a dark glaze or underglaze into a paper cup, about the same of water, a good squirt of dish soap, stirred until the surface foams.

The ratio is a starting point. Thinner gives fainter rings; some strong glazes bubble well with no water at all; stiff matte glazes hardly foam whatever you do. The soap is the part people underdo, and foam that pops before it lands is nearly always a cup that wanted another squirt. Fill the cup no more than half, because the foam needs room to rise.

Dark over light is the rule for the colors: a black, a deep blue or an iron brown over a white or cream base. Two colors of bubbles, one layer each, read as depth. Test on a tile, because every jar on the wall behaves a little differently with soap in it.

Tick list, the cup0 of 4
3

Step three

Blow slowly, let the foam spill, let the bubbles pop where they land.

Blow out, slowly, until the foam climbs out of the cup. Hold the cup at the edge of the pot and let the foam fall onto it; poured foam collapses into a puddle. Turn the pot so the foam lands where you want it. Then watch the bubbles pop, each leaving a ring.

Big bubbles for a plate or a wide bowl, blown slowly. Smaller bubbles for a vertical surface, where a big one is mostly water and runs. If the bisque is drinking the bubbles the instant they touch, mist it lightly first. If they will not pop, a gentle breath across them or a fingertip does it.

Hold the pot level until the rings have dried matte, then a second layer, and a third if you want depth, each dried before the next. Two colors, one layer each, is the classic. Little Street Pottery’s video in the Watch it done section covers controlling where the bubbles land, on greenware and on bisque.

Plates against walls

A plate takes big bubbles because the foam has nowhere to run; it sits, pops and dries in place, and the rings overlap into something like a map. A mug or a vase takes smaller bubbles blown gently so the rings land and pop before gravity gets them, one side at a time, turned on the wheel between sides. The same cup does both; the breath is different.

Tick list, the foam0 of 4
4

Step four

Bubbles are the top layer. Then clean up wet.

Nothing opaque goes over them. Bubbled glaze is the top layer. Bubbled underglaze is bisque fired first, then gets one thin coat of clear and nothing else. Three coats of anything over bubbles buries them, because a coat of glaze is thicker than a ring.

Sponge the beads off the waxed foot. Then the table: the tray, the banding wheel and the tabletop wiped down wet before you leave, and the cup and the straw in the bin. Foam that dries on a shared table is glaze dust on the next person’s work, and a straw left on the table is a straw somebody else picks up.

The dish soap burns out in the kiln with no trace, like wax, so the firing is the ordinary one. Staff load every kiln here, and every piece sits on a cookie with a naked bottom, which the waxed foot gives you. If the piece will hold food or drink, check the glaze you bubbled with on the Food Safe Lookup first. The rings come out of the kiln crisper from underglaze and softer from glaze, and both are the reason people take a photo.

Tick list, finishing0 of 3

Watch it done

Now watch four people blow bubbles at pots.

Watch this one, then go cut a hole in a straw.

None of these potters work here. Between them they cover a full instruction, a three-minute version, a twenty-minute walk through, bubbles on greenware and bisque, and a one-minute mix and bubble. Nothing but the still frame loads until you press play.

Twelve minutes: what you need, the technique, and the finished result. The other four videos are in the comprehensive version.

Start here: the full instruction How to: Bubble glaze full instruction Calder van Andel
Twelve minutes from the same maker as the next video: what you need, the technique, and the finished result. Watch on YouTube
The three-minute version How to: Bubble glaze Calder van Andel
The same maker's three-minute version, for a reminder after the long one. Watch on YouTube
Twenty minutes, start to finish How to bubble glaze on pottery Earth Nation Ceramics
Twenty minutes: materials, applying it, testing glaze combinations, troubleshooting and the finished results. Watch on YouTube
Bubbles on greenware and bisque Beautiful Bubbles on Pottery! BRAND NEW BLOWING TECHNIQUE! Little Street Pottery
Nine minutes on bubbles on greenware and on bisque, with chapters on controlling where they land. Watch on YouTube
One minute How to bubble glaze pottery - tutorial the naked potter
One minute: mixing the cup and bubbling a vase. Watch on YouTube

When it goes wrong

Six ways it goes wrong, and what to do about each.

The three failures that happen on the first cup.

Pick the one that looks like your pot.

How it works here

At The Clay Hole, this is a far-end-of-the-table job with a tray.

This page is written for potters everywhere. A few things are specific to our building, so you know before you start.

Three things to know here

The glaze wall needs the free brush-on glaze and underglaze certification. Underglaze opens at Purple Level (Amaco Velvet at Black Level); at Green and Yellow Level you can bring your own Speedball or Amaco Velvet. Pour a little from a jar into your own cup; never a straw or a soapy brush near a jar, because a contaminated jar is on whoever did it. Tray under the pot, far end of the table, everything wiped down wet before you leave.

The jars

Pour a few spoonfuls from a jar into your cup and put the jar back. A straw, a soapy brush or a soapy cup near a jar contaminates it, the jar is finished, and replacing it is on the member who did it. The glaze wall needs the free brush-on glaze and underglaze certification. Underglaze opens at Purple Level (Amaco Velvet at Black Level); at Green and Yellow Level you can bring your own Speedball or Amaco Velvet.

The table

Far end, a tray under the pot, the pot on a banding wheel. Banding wheels are a studio tool from Yellow up; Green Level Members bring their own. Wax stations are Purple and Black for brush-on work and open to every Level when dipping; for a brushed-on foot at Green and Yellow, bring your own wax.

Leaving it

Tray, wheel and tabletop wiped down wet. Cup and straw in the bin, not the sink. Foam that dries on a table is somebody else’s contamination, and a straw on a table gets picked up.

Firing

Soap burns out in the kiln with no trace. Bisque is cone 05 and free; the glaze firing is cone 5½ at five cents a cubic inch, $4.80 minimum, and every piece sits on a cookie with a naked bottom. Staff load every kiln.

Questions people actually ask

The ones that come up every week.

What is in the cup?

Glaze, water and dish soap. About one part glaze to one part water, then a good squirt of soap, more than feels right, stirred until it foams. Thinner mixes give fainter rings. Some potters skip the water for a strong glaze; test it, because glazes vary in how they bubble.

Glaze or underglaze?

Underglaze bubbled onto raw clay, bisque fired, and covered with one thin coat of clear gives the crispest rings, because underglaze holds detail and clear glaze does not move it. Here underglaze always goes on before the bisque firing and before any glaze, never after. Bubbled glaze works, especially a dark glaze over a light base coat, but the rings are softer. Try both on a tile before a pot.

Which glazes bubble well?

Ones that are fluid enough to foam with soap and dark enough to show against the base: a black, a dark blue, an iron brown, over a white or cream base coat. Stiff matte glazes foam badly. Test on a tile; every jar on the wall behaves a little differently with soap in it.

How do I keep it off my face and out of my lungs?

Blow out, never in, and cut a small hole in the straw near the top so far less can be sucked up. The foam is wet, but popping bubbles can throw fine droplets, so keep your face back. The other risk is a mouthful. Keep it at the far end of the table and away from other people’s work.

Is dish soap safe in the kiln?

Yes. It burns out in the glaze firing with no trace, like wax. The soap in a cup of glaze changes little, and a test tile will show you. Do not put soap in a shared jar; the cup is yours and it goes in the bin when you finish.

Does it need a base coat?

Yes, if you want the rings to read. Three coats of a light glaze, dried, then dark bubbles over it, and nothing on top. Or a raw clay pot with underglaze bubbles, bisque fired, and a clear over. Underglaze bubbles with no clear over them fire dry and rough.

Can I do this at The Clay Hole?

Yes, at the glaze tables, with the free brush-on glaze and underglaze certification, a cup of your own, and a tray under the pot. Pour a little glaze from a jar into your cup; never dip a straw or a soapy brush near a jar. Wipe down wet when you finish, and the cup goes in the bin.

Related lessons

Six lessons that sit next to this one.

Three to read next.

Bubble glaze is a base coat, a banding wheel and a resist with foam on top. These are the pages underneath.

Surface and decorationHow to Use UnderglazeWhat underglaze is for and the rules we keep for it. GlazingGlazing on the WheelHolding a pot still while it turns, with a banding wheel or a wheel. GlazingGlaze Brushing TechniquesThe base coat this page starts from. Surface and decoration40 Ways to Add TextureBubble glaze is entry thirty-seven of forty. Surface and decorationUsing ResistsThe wax on the foot that keeps the foam off the shelf. GlazingTest TilesEvery jar bubbles differently. Test yours on a tile first.

That is the whole technique

Base coat. Hole in the straw. Half and half and soap. Blow slowly. Let them pop. Wipe down wet.

Your first cup will pop before it lands because you were stingy with the soap, and your first plate will have one run down the side because you tilted it. That is normal, and the second plate is the one people ask about. Nothing else on the glaze wall costs a paper cup and looks like it took a week.

If you want the color notes, glaze against underglaze and the answers to the questions everybody asks, switch to the comprehensive version at the top. Otherwise, go find a straw.

Back to Clay Hole University How to use underglaze, and the certification

Written for potters everywhere. Where our studio does things differently, the page says so.