The glaze system at The Clay Hole
Glazing, start to finish
More than 650 commercial glazes and more than 150 underglazes, close to $100,000 of them, and all of it is yours to use. This page is how you learn to use it well.
How to find the glaze you actually want out of a wall of hundreds. How to put it on so it comes out clean instead of streaky. What underglaze does that glaze does not. The handful of rules that keep a shared collection alive. And how to get your piece into the kiln without welding it to a shelf.
Some of this is technique we would teach you standing at the shelves. Some of it is studio rules you have to agree to before your first glaze. Both are here.
There are more than 650 on the shelves, plus more than 150 underglazes, and every one behaves a little differently over every clay body we sell.
Before your first glaze
Get certified once, then never again
Everything on the rest of this page is here whether you are certified or not. But actually reaching for a jar needs one run through the training first, because the collection is shared and one wrong move in it is permanent.
Glaze & underglaze certification
Watch the glazing video, tap through five sets of studio rules, answer eight quick questions, then read and sign the glaze agreement. At the end you save a card with your name on it and show it to any instructor.
About 30 minutes, and most of that is the video. You can stop and come back on the same device.
- 1Who you are
- 2The glazing video
- 3The studio rules
- 4Eight quick questions
- 5Read and sign
Do I have to do this if I have been here a while?+
No. If you were already glazing here before this page went up, you are grandfathered. Nothing changes for you and nobody is going to stop you at the shelves.
We would still love you to run through it. A fair chunk of it is what members ask us at the glaze shelves every single week, and there is now a two-rag rule and a set of underglaze rules that did not exist when you started.
Every new member from here on does need to finish it before their first glaze.
Welcome back.
Step 1 of 5
Who are you?
This is how we record that you finished, so please use the name and email on your membership.
Step 2 of 5
Watch the whole thing
About 21 minutes. It is the same walkthrough we would give you standing at the glaze shelves, only you can pause it. The button below unlocks once you have watched it through.
Watching somewhere we cannot see?
If you opened it in the YouTube app, or your browser blocks us from reading the player, we have no way of knowing how far you got. Tick the box below once you have watched it all the way through and we will take your word for it. Fair warning: the quick check on the other side assumes you actually did.
Step 3 of 5
The rules, five sets of them
Read each set, then tap through. Nothing here is a surprise if you watched the video, but a few of them are worth seeing written down.
Set 1 of 5
Keeping the glaze clean
Cross-contamination is the one that costs real money, so it gets its own set. Five nevers.
- ×A brush never goes into a jarSpoon what you need into the smallest cup that will do the job, and dip your brush in that. A brush that looks perfectly clean still carries traces of the last glaze it touched.
- ×A spoon or tool that has touched another glaze never goes into a jarSame reason. Rinse it properly first, or grab a clean one.
- ×Never pour a cup back unless that cup held one glaze and nothing elseSingle glaze, no layering, nothing else in there? Pour the leftover back in. Layered two glazes in the cup? The whole cup goes in the trash. No exceptions and no judgment calls.
- ×Never add water to a glaze or an underglazeAll of it is water soluble and the water ratio is part of the recipe. If a jar has thickened up or dried out, leave it and grab an instructor. That is genuinely all we want you to do.
- ×Never dip a pot straight into a jarDipping is a separate system with its own buckets, its own glazes and its own certification. Nothing in a jar is for dipping.
Set 2 of 5
Handling the jars
How the jar gets opened, mixed, closed and put back. This is most of what an instructor watches for.
- ×Stir. Never shake.Shaking does not actually mix a glaze, and it drives glaze up into the lid threads where it dries hard. Dried glaze can be as sharp as a razor blade for whoever opens it next. Stroke & Coat bottles are the one and only exception.
- ✓Scrape the crust off the walls back inThat build-up around the inside is minerals and oxides. It is not gunk, it is the recipe, and the glaze needs it back.
- ✓Stir until there are no chunks, then keep going about 30 more secondsWe have tested this more than once. The better mixed a glaze is, the better it fires. The difference is subtle and it is also very real.
- ✓Lid stays on while you workAn open jar sitting out loses water, and the water ratio has to stay precise. Open it, take what you need, close it.
- ×Never squeeze a bottle, never overtighten a lidBoth wreck the bottle, and a wrecked bottle is a jar of glaze nobody can open.
- ✓Wipe the threads and the whole outside before the lid goes back onUse a freshly rinsed, damp rag. This is what keeps the next member from finding a jar they cannot open, or a sharp edge.
- ✓Open jar first, then straight back to its own spotUse whatever is already open before you break the seal on a backup, and check behind for an open one if the front jar is sealed. Every glaze has a labelled place on the shelf and it goes back there before you do anything else.
Set 3 of 5
Your level, and what it opens
Every level here gets high quality glazes. The difference is what the glaze is made of and how hard it is for us to get hold of, not whether it is any good.
- ✓Stay inside your levelGreen Level Members use Green. Yellow adds Yellow. Purple adds Purple. Black Level Members use all four. The sticker on the jar tells you which is which.
- ×Red or orange sticker means staff onlyThose are not a level you can reach. They are ours for studio work.
- ✓Gold sticker is raku and low fireDifferent program, different firing, different day. Not for a normal glaze firing.
- ✓Underglazes work the same waySpeedball underglazes open up at Purple Level. Amaco Velvet underglazes are Black Level Members only. Some of both carry an up-charge, and you pay that on the day you use them.
- ✓Brushes and kit go by level tooGreen Level Members bring their own brushes. Yellow Level gets most studio brushes, but no heat gun and no wax. Purple and Black add the hake and fan brushes, the wax stations, and heat guns if they want them. Everyone air dries, and air drying is the better habit anyway.
- ×Heat guns live on the heat table. Never on the mats.High setting, heat table only. Used on a mat they warp it, and that destroys it. Nobody has to use one, air drying is better, but if you are Purple or Black and you are in a hurry, the heat table is the one place to do it.
Set 4 of 5
Underglaze, and where it differs
Underglaze lives on the same shelves and follows all the same jar rules. There are five places it behaves differently, and this is all of them.
- ✓Greenware or bisque, and we suggest greenwareUnderglaze will go on either. Most people get better results putting it on greenware, so that is what we steer you toward.
- ✓Underglaze gets bisque fired before any glaze goes over itAlways. Underglaze, then a bisque firing, then clear or whatever else you are putting on top. Never glaze straight over wet or raw underglaze.
- ✓Clear over underglaze is required on anything that holds food or drinkAnywhere else it is your call, and bare underglaze can look lovely. Clear Gloss is the one we point people to.
- ✓Thin coats, each one fully dry before the nextUnderglaze put on thick is the single most common reason it comes out badly, closely followed by rushing the drying between layers. Take your time and it behaves beautifully.
- ×Unfired underglaze never goes near a dipping bucketIt comes off in the bucket and contaminates the whole thing. Everything else about jars, brushes, cups, water and mixing works exactly like it does for glaze.
Set 5 of 5
Your pot, the kiln, and cleaning up
The last set is about your own piece and the mess afterwards. The rag rule is new, so read that one properly even if you already know the rest.
- ✓Glaze goes on bisque, never on greenwareYour piece has to go through the fire once first. Bisque is full of open pores, and those pores are what pull the glaze in and hold it there. It dings when you tap it.
- ✓Flash rinse in The Wash Pit right before you glazeThere is always a thin layer of dust on bisque. A fast rinse gets rid of it and your glaze comes out far cleaner. Speed is the point, do not soak the pot.
- ✓Write your glazes downGrab a glaze card or photograph it on your phone. Everybody thinks they will remember. Almost nobody does, and then you cannot make that gorgeous thing a second time.
- ×Zero glaze on the bottomWipe it completely bare and leave an eighth to a quarter of an inch clear above it. An eighth for a very stable glaze, a quarter for anything that runs.
- ✓Every piece needs a kiln cookie you made yourselfThree quarters of an inch wider than whatever actually touches the shelf, rolled thin like a chubby tortilla. A single kiln shelf costs hundreds of dollars, and the cookie is the thing standing between your glaze and that shelf.
- ✓Every piece needs a kiln ticketYour name, the date, which clay you used, every glaze you used, and your order number once you have paid through the QR code. The glaze list genuinely helps us load the kiln safely.
- ✓Two clean rags per visitRinse yours between glazes instead of grabbing a fresh one. Glaze and clay wash straight out of a rag, so one rag goes a very long way. Clean and dirty baskets sit by the office and by The Wash Pit, and please wash a rag out thoroughly before it goes in the dirty basket. Bring your own from home if you would rather.
- ✓Wash brushes by hand, between every bristleAny glaze left in a brush ends up on the next person's pot. Squeeze it back into shape, flick the water out, and put it back in the bin you took it from.
- ✓Clean your stationCups in the trash, tools rinsed in the all-purpose sink, banding wheel wiped top, sides and base. Then your weekly studio job on the way out.
- ✓Collect fired work within two weeksEverything that comes out of the kiln gets a deadline card. Two weeks past it and the piece is thrown away. If you are going away, hold your work back rather than putting it on the shelf before you leave.
Step 4 of 5
Quick check, eight questions
Get one wrong and nothing bad happens. We tell you the answer and you have another go. The point is that you leave knowing it, not that you score well.
Step 5 of 5
Read it, then sign it
This is the studio's glaze agreement. Scroll all the way to the bottom of the box, tick the line underneath, then sign with your finger or your mouse.
The Clay Hole Member Glaze Agreement
12896 S Pony Express Rd, Suite 100, Draper, Utah 84020
Please read through each item on this glaze agreement and make sure that you understand it. This may seem like overkill, but this glaze collection is incredibly expensive and complex and not knowing these things could ruin glaze, hurt the experience for our members, and cost you a lot of money if you don't follow the rules.
- 1)I understand that I am responsible for any pottery glaze and/or bottles that I drop or break, or that I ruin in any other way, and I agree to immediately send The Clay Hole payment at the current retail price for glaze lost plus $10 (for the bottle and the work it takes to replace it).
- 2)I will always wipe (with a freshly rinsed, damp rag) the outside threads of each bottle of glaze before replacing the lid. I will also always wipe the entire outside of each bottle clean.
- 3)I will never overtighten the lids to the glaze bottles that I use.
- 4)I understand that (while rare) dried glaze on bottles can be as sharp as razor blades, and I understand it is up to me to take the correct precautions to protect myself from injury while handling glaze bottles.
- 5)I will never cross-contaminate the glazes that I use, either by pouring used glaze back into the bottle or by dipping measuring tools, spoons, etc. that have been used with other glazes into the bottle.
- 6)I will never squeeze the glaze bottles as this will potentially damage them.
- 7)I will never shake the quart-size glaze bottles. I will only stir the glaze with approved stirring utensils/spoons.
- 8)I will always remove glazes from the shelves with caution and will always replace the glazes I use into the same spot from which I took them.
- 9)I understand that there are no guarantees that any glaze will turn out any such color/look/finish after a kiln firing.
- 10)I agree to thoroughly rinse and replace all tools, measuring cups, brushes, etc. that I use during the pottery glazing process.
- 11)I agree that I will never dip my pottery directly into a bucket or container of glaze unless I have completed The Clay Hole's dipping glaze certification, and then only in the dipping glazes that certification covers and only under the rules of that certification.Updated
- 12)I agree to always keep the lids on the glazes while I use them so that the water ratio of the glaze remains precise.
- 13)I will never dip a paint brush directly into a bottle of glaze or underglaze, even a brush I believe to be clean, and I will always spoon out what I need into a separate cup instead.New
- 14)I will never add water to any glaze or underglaze, and I will never mix two glazes or two underglazes together inside a bottle, without an instructor's supervision.New
- 15)I will never brush glaze onto a piece that has not yet been bisque fired, and I understand that glaze belongs on bisqueware and not on greenware.New
- 16)I understand that underglaze must be bisque fired before any glaze is applied over the top of it, and that unfired underglaze must never go anywhere near a dipping glaze bucket.New
- 17)I understand that underglazes follow the same membership level system as glazes, that Speedball underglazes are available to Purple Level and Black Level members, that Amaco Velvet underglazes are available to Black Level members only, and that some of both carry an up-charge which I agree to pay on the day I use them.New
- 18)I agree to use no more than two clean rags per visit. I will rinse my rag between uses rather than take a fresh one, and I will wash a rag out thoroughly before it goes into the dirty rag basket.New
- 19)I will wipe the bottom of every piece completely clean of glaze, I will make a kiln cookie for every piece I put in to be fired, and I understand that I am responsible for the cost of any kiln shelf that my piece damages.New
By signing below I confirm that I have read and understood every item above. Signed electronically at The Clay Hole, Draper, Utah. Your signature is stored with the date, time and device you signed from.
Scroll to the end of the agreement to carry on.
Use a finger on a phone or tablet, or click and drag with a mouse. We record the date, time, your IP address and the device you signed from, the same way a waiver service does.
Done
You are certified. Go make something glorious.
Here is your certification card. Save it or screenshot it, and show it to an instructor before your first glaze. We have a copy on our end too, so nothing is lost if your phone eats it.
Tap the save button above, or press and hold the card and choose Add to Photos. A screenshot works just as well.
- 1Show the card to an instructorAnyone on the floor. It takes them five seconds and then you are on the system.
- 2Go and look at the Information CenterTest tile pots, the Glaze Bible, the studio favorites, the trending glaze magnet, and a shelf showing every clay body we sell with the same glaze on it. Half an hour there will change what you make.
- 3Start with one glaze on one potLayering is wonderful and it is also where most first attempts go sideways. Get a feel for a single glaze first.
Part one
Finding the glaze you actually want
Six hundred and fifty jars is wonderful right up until you are standing in front of them with no idea where to start. There are four tools in the building built specifically for this, and using them is the difference between choosing a glaze and gambling on one.
The Glaze Bible
Every glaze we carry, with a thumbnail and, for most of them, a test tile number. Printers never get ceramic colors quite right, so treat the photo as a starting point rather than a promise.
Copies live at the glaze shelves. There is also a version online.
The test tile pots
One pot per family of glaze, and very nearly every family we own has one. They show you vertical flow, whether it runs, what it does over shallow and deep texture, and what happens when you fill texture and wipe it back.
Take the tile number from the Bible and go find it on the pot. Closest thing to seeing the result before you commit.
Three ways to find the family on the shelves
Every family has its own illustration, and the same illustration is on the jar stickers and on the shelf label. The front of the Glaze Bible has a legend with a numbered map of the shelves. And big versions of the family stickers run along the top of the shelf system, above whatever sits underneath.
When you are stuck
Look for the studio favorites and the trending glaze magnet. Those move around because members keep pulling spectacular results out of them. The Information Center also has a shelf carrying every clay body we sell with the same glaze on all of them, which is the fastest way to see how much your clay changes the answer.
Two things nobody tells you the first time. Glaze goes through a chemical reaction in the kiln, so the same glaze on the same clay twenty times gives you twenty slightly different results, and occasionally a red goes in and a blue comes out. And leaving part of a pot unglazed is a real look, not a mistake. We call it naked, and a lot of the pottery around the studio has naked areas on purpose.
Which of them you can use
Every jar carries a colored sticker. You use your level and everything below it. There are two sticker colors that are not levels at all: red or orange means it is staff only, and gold means raku and low fire, which never goes into a normal glaze firing.
| Level | Brushes | Drying | Wax | Glazes | Underglazes |
|---|---|---|---|---|---|
| Green | Bring your own | Air dry | Not included | Green stickers | Green stickers |
| Yellow | Most studio brushes | Air dry | Not included | Adds yellow | Adds yellow |
| Purple | Adds hake and fan | Air dry, or a heat gun on the heat table | Wax station | Adds purple | Adds purple, including Speedball |
| Black | Everything we own | Air dry, or a heat gun on the heat table | Wax station | All four colors | All, including Amaco Velvet |
Every level air dries, and air drying is the better habit whatever you pay us. The heat gun is an option Purple and Black have when they are in a hurry, not something they have to use. If you do use one it runs on high and only ever on the heat table, because on a mat it warps it and destroys it. Some glazes and underglazes carry an up-charge whatever your level, and you pay that on the day you use them.
Part two
Every glaze we own, in one searchable list
The Glaze Bible shows you what a glaze looks like. The glaze index tells you what we have, what your level opens, what carries an up-charge and what we no longer stock. It is the thing to open before you drive over, and it is the thing to have in your hand at the shelves.
It took a long time to build and almost nobody knows it exists, which is a shame, because it does considerably more than list things.
Search anything
A glaze name, a whole family, or just a color. Type brown and every brown glaze we carry comes up. You do not have to know what it is called.
Filter it right down
Membership level, color, sheen, family, and effects like reactive, crystalline, celadon, shino, crawl and textured. Narrow to studio favorites, hide anything with an up-charge, hide discontinued.
Surprise me
Three quick questions and it hands you one glaze to go make something with. It is the cure for standing at the shelf for twenty minutes, and yes, there is confetti.
Build your glaze list
Tap any glaze and it lands on your list for today. Tap it again to take it off. Then copy the list, save it as a picture for your phone, or print it and carry it to the shelves.
Share the whole view
One button copies a link that reopens the page with your glaze list and your filters exactly as they are. Send it to a studio friend, or to yourself for next time.
Make it show what you want
Switches for hearts on studio favorites, level colors, up-charge markers and tile numbers. Whatever you choose sticks for next time.
It answers the membership question honestly, too. There is a section that shows exactly what each level opens up, so you can see what moving up would actually get you rather than taking our word for it. It also lists our dipping glazes with how long to hold a piece under, and the raku and flux ranges.
First time in there, hit How it works at the top. It walks you through the whole thing in about six taps.
The index tells you what we have. The Bible shows you what it looks like. Most people end up with both open.
Part three
Putting it on
Glaze goes on bisque, never on greenware. Bisque is full of open pores that pull the glaze in and hold it there, which is what makes it stick properly in the second firing. You can tell a piece is bisque because it dings when you tap it.
Before the brush
Get your kit together first: your brushes, a spoon (or a whisk if the glaze is chunky enough to need one), a cup for each glaze, a freshly rinsed rag, a banding wheel, a glaze card, and the glaze.
Then rinse the pot. There is always a thin film of dust on bisque from sanding, from handling, from sitting on a shelf, and it will show up in your finish. A fast flash rinse in The Wash Pit is all it takes. Speed matters, because bisque starts drinking water the second it gets wet, so this is a flash and not a soak.
Stir your glaze properly before any of it leaves the jar. Scrape the crust off the walls back in, because that crust is minerals and oxides your glaze needs. Stir until the chunks are gone, then keep going about thirty seconds more. We have tested this more than once and the better mixed a glaze is, the better it fires. The difference is subtle and it is also real.
Then spoon it into the smallest cup that will do the job, holding the cup over the jar so anything you spill goes home. Tap and wipe the excess back in. Glaze in the trash is glaze the whole membership paid for, and it is one of the things that pushes membership prices up.
Three coats, three directions
Three coats is the default, and the direction changes every coat: horizontal, then vertical, then diagonal. That is what stops streaks. If every stroke runs the same way you will almost always see it in the finished piece.
Fan and hake brushes are the exception. They hold a lot of liquid and lay it down evenly enough that two coats usually does it. Every other brush wants at least three. Those two brushes are Purple and Black Level.
Let each coat dry properly before the next. The first dries fast because the bisque pulls the water straight in, the second is slower, the third slower still. Air drying is what we would tell you to do, at every level, because a coat that dries in its own time behaves better. Purple and Black Level Members do have heat guns if they are in a hurry, on high and on the heat table only, never on the mats.
Layering is where most first attempts go sideways. It is also where the best results in the building come from, so we are not telling you to avoid it. Just get a feel for one glaze on one pot before you start stacking them, and check the test tile pots for what runs, because two glazes over each other run further than either one alone.
There is a much longer version of this, with brush comparisons and a fix-it section for streaks and crawling, over on the glaze brushing techniques guide.
Part four
Underglaze, and where it differs
Underglaze is color that stays exactly where you put it. It does not move in the fire the way glaze does, which is why people reach for it for detail, line work, lettering and anything that needs to still be recognizable afterwards.
Greenware or bisque, and we suggest greenware
Both work. Raw clay takes it beautifully and gives you cleaner lines, so that is where we point people first.
Thin coats, fully dry between
Applying it too thick is the single most common way a piece with underglaze on it comes out disappointing. It does not look better and it does not fire better. Let each layer dry completely before the next.
It gets bisque fired before any glaze goes over it
Always. Glaze over unfired underglaze lifts, smears and runs. That same rule is why a piece with unfired underglaze on it never goes anywhere near a dipping bucket.
Clear Gloss on anything that holds food or drink
Underglaze on its own is not a sealed surface. Anywhere else, leaving it bare is a genuine look and entirely your call.
Otherwise, treat an underglaze jar exactly like a glaze jar. Stir it, never shake it, spoon it into a cup, no brush in the jar, no water, and no mixing colors together without an instructor. Access follows your level the same way: Speedball opens up at Purple Level, Amaco Velvet is Black Level Members only, and some of both carry an up-charge you pay on the day.
Our commercial underglazes all fire well at the temperature we fire to, so you do not need to worry about a color burning out on you.
Part five
The rules that keep this possible
Every jar on those shelves is a balanced recipe. Minerals, oxides, crystals and a water ratio somebody measured. Get another glaze into it, or get water into it, and it never fires the same way again. Not for you, and not for the next four hundred people who reach for it.
That is the honest reason for all of this. Not because we enjoy rules, but because contamination is quiet. Nothing looks wrong at the shelf, nothing looks wrong on the pot, and it turns up months later on somebody else's work.
Nothing goes into a jar
- ·No brushes, ever, even ones you believe are clean
- ·No spoon or tool that has touched another glaze
- ·No water, ever, without an instructor
- ·Leftovers only if that cup held one glaze and nothing else. Two glazes in the cup and the cup goes in the trash
Stir, never shake
- ·Shaking does not break up the solids anyway
- ·It pushes glaze into the lid threads, where it dries razor sharp for whoever opens it next
- ·Stroke & Coat is the one family you may shake
- ·Lid stays on while you work so the water ratio holds
Treat the jars gently
- ·Never over-tighten a lid and never squeeze a bottle
- ·Wipe the threads and the whole outside with a freshly rinsed rag before the lid goes back on
- ·Back in its own labeled spot, every time
- ·Open jar in front, sealed backups behind it. Always use the open one
Two rags per visit
- ·Glaze and clay rinse straight out of a rag, so rinse the one in your hand instead of taking a fresh one
- ·Wash it out thoroughly before it goes in the dirty basket
- ·Clean and dirty baskets sit by the office and by The Wash Pit
- ·Rather bring rags from home? Please do, we are not precious about it
If you do ruin a jar, you replace it. That runs $15 to $40 a bottle. We would much rather never charge anybody, which is the entire reason the certification exists, and it is also why nobody has ever been in trouble here for stopping to ask first.
Part six
Getting it into the kiln
Three things stand between a finished pot and a fired one, and the first of them is the one that costs the studio real money when it goes wrong.
Wipe the bottom
Completely bare, and leave an eighth to a quarter of an inch clear above it. An eighth is fine for a very stable glaze. A quarter gives a runny one somewhere to go. Tidy the inside up too if you left it naked, because the more care you put in now the happier you will be when it comes out.
Make a kiln cookie
Every single piece gets one, and you make it yourself out of scrap clay. Three quarters of an inch wider than whatever actually touches the shelf. The total width of your piece does not matter, only the footprint. Roll it thin, like a chubby tortilla, trim it round with a needle tool, and use a clay the same color as your pot. There are barrels of wet scraps if you can find the right consistency.
The reason is simple. If glaze runs off your piece, or you missed a spot on the bottom, the cookie sticks to your pot instead of your pot sticking to the kiln shelf. A single kiln shelf costs hundreds of dollars.
Fill in a kiln ticket and pay
One ticket per piece: your name, the date, the clay you used and every glaze you used. That last one genuinely matters, because it tells us how to load the kiln. Every ticket has a QR code that takes you to the firing calculator. Put in the length, width and height, check out, and write your order number on the ticket. Then set your cookie down on the table, put your pot on top of it, and leave the ticket with it. We take it from there.
Bisque firings are free. You only ever pay for the glaze firing, and current prices live on the kiln firing page.
Then come back for it
Everything that comes out of a kiln gets a deadline card. You have two weeks. After that it goes in the trash, which we hate doing, so if you have a vacation coming up just hold your work back until you are home.
And clean up
Glaze cups go in the trash. Tools get rinsed in the all-purpose sink, and the water pressure there is stronger than it looks, so ease it on. The gray sponges next to the sink are good for spoons.
Brushes get washed by hand, and you have to get in between every bristle, because any glaze left in a brush turns up on the next member's pot. Squeeze it back into shape, flick the extra water out, and put it back in the bin you took it from. Every brush bin is a different job and mixing them up confuses everybody. Then wipe your station, clean the banding wheel on the top, the sides and the base, and do the weekly studio job every member does.
Part seven
The short version, and what to do when it goes wrong
Everything above, condensed to the bit you actually need while you are standing at the shelves.
Why did my glaze come out a completely different color?+
Because that is what glaze does. Every glaze goes through a chemical reaction in the kiln. You can put the same glaze on the same clay twenty times and get twenty slightly different results, and sometimes a red goes in and a blue comes out. There are no guarantees on color, finish or look, and that is genuinely part of the fun. It is also exactly why we tell you to write your glazes down, because the ones that come out astonishing are the ones you will want to repeat.
My finish came out streaky+
Almost always direction. If every coat ran the same way, the overlaps line up and you see them. Horizontal, then vertical, then diagonal fixes it on the next piece. The other common cause is going on to the next coat before the last one was properly dry, which drags the coat underneath around.
It came out thin and patchy+
Usually too few coats, or a glaze that was not stirred enough before it left the jar. Most brushes need three coats. Fan and hake brushes carry enough that two will do it, and they are the only exception.
Does the clay body change the glaze?+
Yes, noticeably. There is a shelf at the Information Center with every clay we sell, all carrying the same glaze, so you can see it for yourself. Worth five minutes before you commit to a color on a piece you care about.
Will glaze wash out of my clothes?+
Almost always, yes. The exception tends to be the iron based glazes, the deep brick reds. Those occasionally stay. There are no guarantees, but other than the iron reds we have very rarely seen a glaze win against a washing machine.
What about the dipping glazes?+
Different system entirely, with its own buckets, its own rules and its own training. Everything on this page covers what comes in a jar. If you want the buckets, start at the dipping glaze certification.
The studio cheat sheet
Glazing and kiln prep, start to finish
Every step in order, on one screen. This is the part worth screenshotting for your first few weeks at the glaze shelves.
1Find and prep
- Pick a glaze in the Glaze Bible.Thumbnails for all of them and a tile number for most. Printers are not perfect, so treat the picture as a starting point.
- Check it on the test tile pot.Find that tile number. The pot shows you flow, shallow and deep texture, and whether it runs.
- Find the family on the shelves.Match the illustration on the jar sticker and the shelf label, or use the numbered legend in the front of the Bible.
- Check the sticker color.Your level and below only. Red or orange is staff. Gold is raku and low fire, never a normal glaze firing.
- Flash rinse the bisque.A second in the wash pit takes the dust off and gives you a cleaner finish. Do not soak it.
- Write your glaze names down.Glaze card or a photo on your phone. Nobody remembers, and you will want to make it again.
2Apply
- Stir. Never shake.Scrape the crust off the walls back in, stir the chunks out, then keep going about 30 seconds more. Stroke & Coat is the one bottle you may shake.
- Spoon into the smallest cup that will do.Hold the cup over the jar, tap and wipe the excess back in. Your brush never touches the jar.
- Coat one, horizontal.Let it dry completely first time. The bisque drinks this coat, so it goes fast.
- Coat two, vertical.Slower to dry than the first. Wait it out.
- Coat three, diagonal.Changing direction each coat is what kills streaks. Fan and hake brushes hold enough that two coats usually does it.
- Lid on, no water.Lid stays on while you work so the water ratio holds. Never thin a glaze yourself. Ask an instructor.
3Finish and kiln prep
- Bottom completely bare.Wipe it clean and leave 1/8 to 1/4 inch clear above it. A quarter inch if the glaze runs, an eighth if it is very stable.
- Leftovers back, or bin the cup.Back in the jar only if that cup held one glaze and nothing else. Two glazes in the cup means the cup goes in the trash.
- Wipe the threads and the jar.Freshly rinsed rag. Dried glaze on threads can cut the next person opening it.
- Jar back in its own spot.Open jar in front, sealed backups behind it. Always use the open one first.
- Make a kiln cookie.Scrap clay, rolled thin, 3/4 of an inch wider than the part that touches the shelf. It saves a shelf worth hundreds.
- Kiln ticket, filled in and paid.Name, date, clay body, every glaze you used, and your order number from the QR code.
- Two rags per visitRinse the rag between glazes instead of taking a fresh one. Glaze and clay wash straight out. Wash it out thoroughly before it goes in the dirty basket. Clean and dirty baskets are by the office and by The Wash Pit.
- Two weeks to collectEverything that comes out of the kiln gets a deadline card on it. Anything still sitting there after two weeks goes in the trash, so do not put work in right before a vacation.
- Up-charges the same dayIf your glaze or underglaze carries an up-charge sticker, it is per piece and you pay it through the website on the day you glaze, same as a firing.
One last thing
We would rather share it than protect it
Most studios this size do not hand members the keys to a hundred thousand dollars of commercial glaze. We do, and we would like to keep doing it. The only thing that makes that possible is every member handling the shelves the same careful way.
So thank you for reading all of this. Now go and put something beautiful in the kiln.
Questions about any of this? Ask any instructor on the floor, or get in touch. Nobody has ever been in trouble for asking first.