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Every question below came from somebody standing at a wheel or holding a piece that did not turn out. The answer is the first sentence. The rest is why, and what it costs to get it wrong.
149 questions
The first few weeks, and what nobody warns you about.
Pottery is easy to start and slow to get good at, and those are two different things. Most people make something recognizable in their first session and something they actually like within a few months. The wheel is the harder half, because it asks your hands to do two different jobs at once while the clay punishes hesitation. Hand building rewards patience instead of reflexes, so it feels easier sooner.
How to throw on the wheelPlan on three to six months of regular sessions before you make a piece you would give away. The first month is spent learning what the clay does, the second learning to stop fighting it. Everyone hits a stretch where the work gets worse before it gets better, usually right after the beginner’s luck runs out. That stretch is the normal part, not the sign you should quit.
Let yourself be bad at something againNone. Every potter has thrown a bag of clay into the reclaim bucket in frustration, and most did it in the first week. What you need is a willingness to make bad work for a while, and to come back the following week. Skill in drawing, sculpting or any other craft transfers less than people expect, because the clay teaches its own lessons.
Start with whichever one you are excited about, and try the other one inside your first month. The wheel gets the attention and produces round work fast once it clicks. Hand building has no speed limit and no centering problem, and it makes shapes the wheel cannot. Potters who only ever learn one of the two end up designing around what they can make rather than what they want to make.
A beginner’s guide to sculptingClothes you would not mind ruining, and short nails. Clay splatter washes out of most fabric but glaze and slip can stain, and wet clay finds every seam. Closed shoes, hair tied back, and no rings or bracelets on your throwing hand. Long sleeves get in the way more than they protect.
What to wear and bringA basic kit is a wooden rib, a metal rib, a wire tool, a needle tool, a sponge and a trimming tool, and that covers almost everything for the first year. Beyond that, tools solve specific problems rather than making you better generally. Buy the next tool when a job keeps annoying you, not before.
Helpful pottery itemsOnce a week keeps you improving. Twice a week is where progress stops feeling slow. Long gaps cost more than they should, because throwing is muscle memory and muscle memory fades faster than knowledge. A short session where you throw five of the same form beats a long session where you make five different things.
The wheel practice planBecause you are comparing your first month to their third year, and because you see their finished shelf and your own reject pile. Everyone in a studio is quietly convinced that everyone else has it figured out. The honest version is that most potters throw several pieces for every one they keep, and nobody photographs the others.
Comparison is the thief of joyYes, with technique changes. Long nails press into the wall where your fingertip should, so you work with the pads of your fingers turned sideways, use a rib in place of the inside hand more often, and keep the nails clean because clay packs under them. It is harder, not impossible, and plenty of potters do it.
How to throw with long fingernailsUsually yes, with adjustments. Wheel height, stool height, smaller clay amounts, more ribs and fewer bare-hand pulls all reduce load. Hand building at a table is gentler on hands than centering is. Wedging is the single hardest part on wrists, and there are ways around it.
Pottery with arthritisIn everyday use they mean the same thing. Strictly, ceramics is the whole field of fired clay and related materials, and pottery is the part of it that makes vessels. Nobody in a studio will correct you either way, and the words get used interchangeably on every shelf in the building.
The plain English pottery dictionaryFar less than buying a wheel and a kiln, which is the comparison most people never run. A studio membership covers the equipment, the firing and the space. A home setup means buying all three and then finding somewhere to put them. The full arithmetic, itemized down to the electrician, is on its own page.
How much does pottery costA monthly membership buys a set number of instructed classes, shelf space to keep work on, and access to the studio’s wheels, slab rollers, glazes and kilns. At The Clay Hole the levels run Green, Yellow, Purple and Black, and the difference between them is class count, shelf size, clay discount and what glazes are included.
Membership levels explainedYourself and a signed waiver. Everything else is in the building. Come with your nails short, your hair tied back and the expectation that you will get clay on you. Bring a drink and a towel if you like having your own.
New member welcomeWhat it is, what the numbers mean, and how to keep it workable.
Clay is weathered rock, mostly aluminum silicate minerals, ground fine enough that the particles are plate shaped and slide past each other when wet. That plate shape is the whole reason clay is plastic and sand is not. A commercial clay body adds other minerals to control how it fires, how strong it is when dry, and what color it ends up.
The complete guide to clay bodiesThey differ by how hot they fire and how much water the fired body absorbs. Earthenware fires low and stays porous, so it needs glaze to hold liquid. Stoneware fires higher and ends up nearly waterproof on its own. Porcelain fires higher still, is whiter, more translucent and less forgiving to throw. The studio’s clays are all mid-fire stoneware and porcelain.
The complete guide to clay bodiesA cone measures heatwork, which is temperature and time together rather than temperature alone. Orton cones are small pyramids formulated to bend at a known amount of heatwork, so a kiln fired slower reaches the same cone at a lower peak temperature. That is why a clay is sold by cone rather than by degrees.
The pottery cone chartWedging makes the moisture even and lines up the clay particles, which is what stops a pot pulling itself off center as you throw. Removing air is a side effect rather than the main job. Clay straight from a fresh bag is already fairly homogenous, but clay that has been reclaimed, stored or cut needs it.
How to wedge clay properlyUsually nothing dramatic. The pot drifts off center as you pull, the wall thickness goes uneven, and the piece is more likely to warp as it dries. Air pockets are a smaller risk than the stories suggest, because most pockets get worked out during throwing. Uneven moisture is the real cost, and it shows up at the rim.
How to wedge clay properlyPress a thumb into the block. If it takes the print easily and stays slick, it is throwing wet. If it resists and the edges of the print crack, it is stiff. Stiff clay is harder to center and tires your hands out. Wet clay collapses at the top of a tall pull. Most people find a bag is at its best a week or two after opening.
Waking up stiff clayYes, if it is not bone dry. Leather-hard and stiffer clay can be sliced, wetted between the slices and wedged back together over a day or two. Fully bone-dry clay is easier to slake down completely in water and reclaim than to rescue by hand.
How to reclaim clayA standard bag is 25 pounds, which is enough for roughly twenty mugs, six to eight medium bowls, or one large piece with clay left over. One bag is a realistic month for someone coming once a week.
The clay weight chartGrog is fired clay ground back into particles and mixed into a clay body. It opens the body up, which means it dries more evenly, shrinks slightly less and resists cracking on big or awkward forms. The trade is texture: grog is abrasive on your hands and shows in the fired surface.
The plain English pottery dictionaryMost mid-fire stoneware loses about ten to fourteen percent from wet to fired, and the exact figure is printed on the bag. That is why a lid thrown to fit a pot on the same day fits after firing, and a lid thrown to fit a pot that is already leather hard does not.
The shrinkage calculatorOnly if they fire to the same cone and shrink at close to the same rate. Mixing bodies with different shrinkage puts the join under stress every time the piece changes size, and it cracks in the kiln or later. Two bodies from the same manufacturer at the same cone usually get along. Mixing for color is a whole technique of its own.
Throwing with colored clayReclaim is clay scrap that gets dried out, slaked down in water, dried back to working consistency and wedged up again. It is the same clay, and there is no quality loss as long as nothing foreign went into the bucket. Colored clay never goes into a communal reclaim bucket, because the color never comes back out.
Reclaiming your clay, worth it or notAlmost never. Pots explode because water trapped in a thick or damp wall turns to steam faster than it can escape. An air pocket on its own just expands a little and usually pushes out through the wall. Thickness and moisture are what to worry about.
Why did my pottery do thatNo. Air dry clay is a craft material that never gets fired, stays water soluble and will soften or fall apart if it gets wet. Fired pottery clay goes through a chemical change in the kiln that cannot be undone. Anything meant to hold food or water has to be fired.
A clay body is a recipe, not a single mineral. Manufacturers blend several clays with fluxes and fillers to hit a target color, texture, firing range and shrinkage. Two bags both labelled stoneware can behave completely differently, which is why potters get attached to one body and stay there.
The complete guide to clay bodiesCentering, pulling, and the eleven ways a pot goes wrong.
Almost always because the clay is moving your hands instead of your hands moving the clay. Centering is braced pressure, not strength: elbows locked into your body or your thighs, hands still, wheel fast, and the clay forced to come to the fixed point you are holding. If your arms are floating, the lump wins every time.
How to center clayFast for centering and opening, slower as the walls get taller and thinner. A tall thin wall at high speed has more centrifugal force pulling it outward than it has strength to resist, which is how pots flare and collapse at the top of a pull. If the rim is wobbling faster than you can react, slow down.
How to throw on the wheelUsually the clay was not fully centered before you opened it, and opening revealed it. It can also be uneven downward pressure when opening, or a hand that drifts as it moves in. Stop, collar the wall back in, re-center the rim and carry on rather than fighting a pot that is already crooked.
Opening clay and setting the floorBecause each pull started too high. A pull has to begin under the clay that is left, at the very base, and squeeze from there. Starting an inch up leaves that inch behind permanently, and after three pulls you have a thin cylinder sitting on a heavy pad.
How to throw on the wheelAn S crack is a curved split in the middle of a pot’s floor, and it appears during drying or after the bisque. It comes from a floor that was never compressed, or from clay particles left aligned outward by opening. Compress the floor with a rib after opening and again before you finish, and most of them stop happening.
Compressing the floor and the rimToo much water, too many pulls, or a wall that went thin before it went tall. Water softens the wall faster than most beginners expect, so sponge the inside dry between pulls. Every pull also work-softens the clay, so four good pulls beat eight timid ones.
What to check when throwing goes wrongAbout a quarter of an inch for most functional work, a little thicker at the base and a little thinner at the rim. Thinner looks impressive and chips easily. Thicker feels clumsy and takes longer to dry evenly. Pinch the wall between finger and thumb to check rather than guessing by eye.
Proportions, ratios and wall thicknessUse a bat for anything wide, flat or too delicate to cut and lift, which means plates, platters and wide bowls. Throw straight on the wheel head for mugs and small forms, because it is faster and there is no bat wobble to fight. A badly seated bat is worse than no bat.
To bat or not to batLet the wheel stop, clean the water out of the base, run a wire under the pot with the wire held taut and flat against the wheel head, then wait. A pot lifted straight after wiring often distorts because the water underneath has not released. Cutting twice and letting it sit for a minute solves most of it.
Getting a pot off the wheelThrowing off the hump means centering one large lump and making several small pots from the top of it, cutting each one off as you go. It is how production potters make twenty of the same cup. The skill is centering only the top portion each time rather than the whole mound.
How to throw off the humpA wavy rim is uneven wall thickness showing up at the weakest point. It also happens when a pull ends abruptly instead of easing off, or when the rim is left unsupported and soft. Compress the rim with a finger and a sponge at the end of every pull, and trim the rim level with a needle tool if it has drifted.
Trimming an uneven rimTwisting comes from pulling faster than the wheel is turning, so your hands drag the clay around rather than up. Slow your hands, or speed the wheel up slightly. It also happens when the wall is too dry and grabs.
How to stop pots twistingEnough to keep your hands sliding and no more. Water is a lubricant, not an ingredient. Standing water inside the pot soaks the floor and is the most common cause of a base that cracks later, so sponge it out every time.
What to check when throwing goes wrongConing is pushing the clay up into a tall cone and pressing it back down, usually two or three times before centering. It evens out moisture and aligns the particles, which is wedging finished on the wheel. It is also the fastest way to tire your forearms out if you do it for longer than you need to.
How to throw on the wheelNot to the clay. Most potters in the west throw counter-clockwise with the left hand inside, and most studio wheels are set up that way, but the physics is identical in reverse. If you are left handed, try both directions early rather than assuming one is correct.
Centering usually clicks somewhere between the third and the tenth session. A recognizable cylinder follows soon after. Control, which means making the same thing twice on purpose, takes months. Nobody gets there without throwing a lot of pots they do not keep.
The wheel practice planSlabs, coils, pinch pots and joins that survive the kiln.
A slab is a flat sheet of clay, rolled by hand with a rolling pin or run through a slab roller. Almost every hand-built box, mug, tile and tray starts as one. Slabs are cut and joined while soft or shaped while leather hard, and the two give very different results.
How to make a slab mugA coil pot is built from ropes of clay stacked and blended together. It is the oldest way of making a vessel and it has no size limit, which is why the biggest historical pots are coiled rather than thrown. Blending the coils properly on both sides is what makes the wall one piece instead of a stack.
Coil buildingA pinch pot is made by pressing a thumb into a ball of clay and thinning the wall between thumb and fingers while turning it. It is the first thing most people ever make and it stays useful, because it gives total control over thickness and needs no equipment at all.
How to make a pinch potScore both surfaces with a needle tool or a serrated rib, wet them with slip made from the same clay, press them together firmly enough to squeeze slip out of the seam, then blend the join on both sides. Skipping the blending is what makes a join that looks fine and opens in the kiln.
Score and slip a join that survivesScore means scratching a cross hatch into both surfaces. Slip is clay thinned with water to the consistency of thick cream. Together they give the two pieces a mechanical key and a shared layer of clay, so they dry and shrink as one thing rather than two.
Score and slip a join that survivesAlmost always because the handle and the body were at different moisture levels when they were joined. A soft handle on a leather-hard mug shrinks more than the mug does and pulls itself off the join as it dries. Match the two stages, join properly, and dry the whole piece slowly with the handle covered.
How to pull handlesAbout a quarter of an inch for most work, a little thicker for anything load bearing and a little thinner for small delicate pieces. Thin slabs warp, thick slabs are heavy and dry unevenly. Roll to an even thickness using guide sticks rather than trusting your eye.
Slab rollers and slab moldsA slab mold is a form you drape or press a clay slab over or into, so the slab takes its shape while it stiffens. Hump molds shape the outside, slump molds shape the inside. This is not slip casting, which pours liquid clay into a plaster mold and is a different process entirely.
The slab mold roomYes, and some of the best work does. A thrown cylinder with a hand-built spout, a slab box with a thrown lid, a thrown form altered while soft. The only rule is the one that governs every join: match the moisture, score and slip properly, and dry the whole thing at one speed.
Either it was too dry, or the outside of the curve was stretched further than the clay could go. Bend slabs when they are soft leather hard, support the inside of the curve, and go slowly. Compressing the outside of the bend with a rib afterwards closes the small tears before they become cracks.
Why did my pottery do thatA sprig is a small relief decoration pressed out of a tiny mold and applied to the surface of a piece. It is how classic jasperware gets its raised white figures. Sprigs go on at leather hard with a little slip, and they need the same moisture matching as any other join.
Sprig moldsNo, but it is much faster and much more even. A rolling pin and two guide sticks of the right thickness will produce a good slab. A slab roller will produce twenty. The studio has slab rollers, and using them takes a short certification because the rollers and the slab molds can both be damaged by misuse.
Slab rollers and slab moldsThe stage that ruins more work than any other.
A mug takes a few days, a large or thick piece can take two weeks, and the honest answer is that it depends on thickness, form, humidity and airflow far more than on the calendar. Utah’s dry air speeds everything up, which is good for turnaround and bad for cracks. Slow is almost always safer.
How to tell if your pottery is bone drySlip, plastic, leather hard, bone dry, bisque and glaze fired. Plastic is throwing and building. Leather hard is firm enough to hold its shape and soft enough to carve, trim and join. Bone dry is as dry as air alone will make it, pale and room temperature to the cheek. Only bone-dry work can be fired.
The five stages of clayLeather hard is the stage where clay holds its own shape but can still be cut, carved, trimmed and joined. It feels cool and firm, takes a fingernail mark without squashing, and darkens if you wet it. Almost every finishing operation happens in this window, which is why potters plan their week around it.
The plain English pottery dictionaryBone dry means no free water is left in the clay and it will not get any drier in room air. It looks uniformly pale, feels room temperature rather than cool against your cheek, and no longer darkens where you touch it. A piece that is still cool in one spot is not ready for the kiln.
How to tell if your pottery is bone dryBecause one part dried faster than another and the shrinkage pulled it apart. Rims, handles, spouts and thin edges dry first. Floors, bases and thick joins dry last. The fix is to slow the fast parts down rather than speed the slow parts up, which means covering the exposed edges.
Cotton sheets or plastic bagsCover it when the piece has thin parts, attachments or a wide flat floor, and leave it open when it is simple and even. Loose plastic slows drying, tight plastic stops it almost completely, and a cotton sheet under plastic evens out the difference. What you are managing is the rate difference across the piece, not the total speed.
Cotton sheets or plastic bagsYes, and it is the fastest way to crack good work if you do it wrong. Heat and airflow dry the surface faster than the inside, which sets up exactly the stress that splits a piece. Use them on simple even forms once the piece is already firm, never on something with a fresh handle.
The hanging heat lampsThe join dries and shrinks at a different rate to the wall it is attached to. The handle is exposed on all sides and dries first, the mug wall dries slowly, and the difference tears the seam. Wrap the handle loosely in plastic for the first day so it catches up.
How to pull handlesFlat work has no wall to hold it up and nothing but the floor to compress. Dry it upside down on a flat board once it is firm enough to handle, keep the rim covered so the edges do not race ahead, and give it far longer than you think it needs. Plates warp weeks after everyone thought they were safe.
How to throw platesHold it against your cheek. Cool means water is still evaporating out of it. Room temperature all over, including the thickest part and the inside of the foot, means it is bone dry. Color helps but lies on darker clays, and weight only helps if you weighed it before.
How to tell if your pottery is bone drySometimes, and it is risky. Spraying a bone-dry piece makes the surface swell against a dry interior, which cracks it. Wrapping it in damp cloth inside a bag for a day or two rewets it slowly enough to sometimes work. A piece that got away from you is usually better reclaimed than rescued.
How to rescue pottery at any stageA damp box is a sealed container with a plaster slab in the bottom that keeps humidity high, so work can sit for days or weeks without drying past leather hard. It is how potters keep a multi-session project workable. They are easy to make.
Making your own damp boxLeather-hard work, feet, carving and finish.
Trimming is cutting away the excess clay from the outside and base of a leather-hard pot on the wheel, which shapes the foot and sets the final weight. It is where a decent pot becomes a good one, and where an impatient week turns into a hole through the bottom.
Turning and trimming on the wheelWhen it is firm enough to hold its shape upside down without deforming, and still soft enough that the trimming tool peels a ribbon rather than dusting. Too wet and the rim distorts under its own weight. Too dry and the tool chatters and the surface tears.
Turning and trimming on the wheelA foot ring is a raised rim of clay left on the base so the pot sits on a narrow circle rather than its whole bottom. It lifts the piece visually, keeps glaze runs off the shelf and makes a pot easier to pick up. Plenty of good work has no foot at all.
Adding feet and foot ringsKnow how thick the floor is before you start. Tap the base and listen, or press a needle tool through a scrap area while throwing and measure. Trim the outside profile first and the foot last, and take the last passes shallower than feels necessary.
Fixing a bottom thrown too thinBurnishing is polishing leather-hard or bone-dry clay with a smooth stone, a spoon or a plastic rib until the surface takes on a soft shine. It works by aligning the surface particles, not by adding anything. The shine survives a low firing and is lost at high temperatures.
Burnishing and terra sigillataSgraffito is scratching through a layer of colored slip or underglaze to reveal the clay underneath, so the design is drawn by what you remove. It works best at leather hard, when the slip has set but the clay still cuts cleanly.
Carving and sgraffitoMishima is inlay. You carve a line into leather-hard clay, fill it with a contrasting slip, let it set, then scrape the surface back so only the filled line remains. The result is a crisp flush drawing that looks printed rather than painted.
Mishima, slip inlaid into carved linesMost potters press a stamp or scratch initials into the foot at leather hard. A stamp is faster, more consistent and easier to read after glaze. Sign before the piece dries, because signing bone-dry clay chips it and signing after bisque means scratching through a hard surface.
Making your own stamps and maker’s markYou can grind and sand bisque, but you cannot really carve it. Bisqueware is hard, brittle and dusty, and any cutting produces silica dust that must be handled wet. Do the carving at leather hard, where the clay cooperates.
Scouring, sanding and grindingTerra sigillata is an ultra-fine clay slip, made by letting a thin clay and water mixture settle and taking only the finest particles from the middle. Brushed onto bone-dry work and buffed, it gives a satin sheen without glaze. It is the surface on a lot of ancient pottery.
Burnishing and terra sigillataWork the surface while the clay is still wet with a metal rib, which compresses rather than removes. Smoothing with a wet sponge feels effective and actually raises the coarser particles and leaves a soft fuzzy surface. Sponging is for cleanup, ribbing is for finish.
Using ribs while you throwSand bisqueware only for real defects, always wet, and never dry. Dry sanding fired clay releases silica dust that is genuinely dangerous to breathe. Most of what people sand away at bisque could have been ribbed away in thirty seconds while the clay was wet.
Masks and respiratorsWhat glaze is, how much to put on, and why it lied to you.
Glaze is glass that has been persuaded to melt at a temperature clay can survive and to stick to it afterwards. Three families of ingredient do the work: silica makes the glass, flux lowers its melting point, and alumina stiffens it so it stays on a vertical wall instead of running to the shelf. Color comes from metal oxides on top of that.
What pottery glaze actually isUnderglaze is colored clay in a brushable form. It holds a line, does not move in the firing, and is matte and porous on its own. Glaze melts into glass and moves. Underglaze is what you draw with. Glaze is what you seal with. Most colored work is underglaze under a clear glaze.
How to use underglazeThree even coats is the standard for most brush-on glazes, and the jar will say so. Two comes out thin, patchy and often a completely different color. Let each coat lose its shine before the next one, and cross-hatch the direction so the brush marks cancel out.
Glaze brushing techniquesNot enough glaze on the pot, nearly every time. Brush-on glazes are formulated for a specific thickness and there is no way to fake it. Dusty or greasy bisque also repels glaze, so wipe the piece with a damp sponge before you start and handle it by the foot.
Glaze problems, causes and fixesBecause the jar shows it at the right thickness, on a specific clay, at a specific firing. Change any of those and you get a different result. The same glaze over a dark body and a white body can look like two products. Test tiles on your own clay are the only reliable answer.
Making and dialing in test tilesCrawling is glaze pulling away from the surface in the kiln and leaving bare patches with thick beaded edges. It is caused by something between the glaze and the clay: dust, grease, a fingerprint, or glaze applied so thickly that it cracked as it dried. Clean bisque and even application prevent nearly all of it.
Glaze problems, causes and fixesCrazing is the fine network of cracks that appears in a glaze when the glaze shrinks more than the clay under it as they cool. It is a fit problem between glaze and body, not a firing mistake. It can appear months later. On functional ware it is worth avoiding, because those cracks hold water and stain.
Glaze problems, causes and fixesPinholing is small holes left where gas escaped through the glaze as it melted and the glaze did not heal over. Gas comes from the clay body, from organic matter, or from glaze applied over a dusty surface. A slower cool or a short hold at temperature usually closes them.
Glaze problems, causes and fixesGlaze ran to the bottom and welded the pot down. Leave the bottom quarter inch of the pot bare, wipe the foot twice, and use a glaze catcher under anything that is likely to run. Thick application near the base is what turns a nice glaze into a repair job.
Fixing fused and sharp potteryNot on the part that touches the shelf. Everything else is fair game, and glazing the underside of a foot ring is normal as long as the ring itself is clean. Anything glazed all over has to be fired on stilts, which leaves marks and is not used for functional stoneware.
Wax resist is a liquid wax painted onto bisque where you do not want glaze. Glaze beads off it, and the wax burns away in the firing. It is the fast way to keep a foot clean and the only practical way to make crisp glaze edges and overlaps.
Using resists for effectLayering two glazes is one of the most rewarding things in ceramics and one of the easiest ways to ruin a kiln shelf. Overlaps melt at a lower temperature than either glaze alone and run further than either would. Test on a tile first, keep the overlap well above the foot, and use a catcher.
The Mega Glaze ToolA dipping glaze lives in a bucket rather than a jar, and the piece is dipped into it for a couple of seconds. It gives a perfectly even coat in one go, which is why production potters use it. At The Clay Hole dipping is certified work, because getting the density and the timing wrong wastes a whole bucket.
How to use dipping glazesFor almost all studio work, yes. Bisque makes the piece strong enough to handle, and porous enough to suck the water out of the glaze so it grips. Single firing is a real technique but it needs a glaze formulated for it and a much more careful application.
What a kiln firing actually doesUsually yes. A fired glaze surface is glassy and does not absorb, so the new coat has to be applied thinner and given longer to dry, and the piece needs a second firing. Results are less predictable than the first time, and a matte or crawled surface reglazes better than a glossy one.
Reglazing and refiringA glaze is safe for food when it is fully melted, fits the clay without crazing, and contains no soluble metals that can leach. Manufacturers test their glazes and state the result, so the honest answer for studio work is to use glazes rated for it and apply them properly. Claiming food safety is a bigger commitment than most people realize.
Food safe, dishwasher safe, what you can claimLusters and overglazes are metallic or colored coatings applied on top of an already glazed and fired piece and fired again at a low temperature. They produce real gold, platinum and mother of pearl effects. The Clay Hole does not stock them, so members who want them bring their own.
How to use overglazes and lustersBecause the clay underneath is part of the finished color. Iron in a dark body bleeds up into the glaze and shifts it. A white body reflects light back through the glass and keeps it bright. Any glaze that is translucent is showing you the clay as much as itself.
The Mega Glaze ToolWhat the heat actually does, and what it costs.
The bisque firing drives out the last chemically bound water and burns away organic matter, and it permanently converts clay into ceramic. After bisque the piece can never be turned back into clay. It comes out hard, porous and pale, ready to take glaze.
What a kiln firing actually doesThe glaze melts into glass, bonds to the clay surface and, at mid-fire and above, the clay body itself tightens up and stops absorbing water. That second part is why stoneware holds liquid even where it is unglazed. Both changes happen in the last stretch of the firing.
What a kiln firing actually doesA full cycle is usually somewhere between eight and fourteen hours of heating, plus at least as long again to cool before the kiln can be opened safely. Cooling is not waiting around: the rate a kiln cools changes what the glaze looks like, and opening it early cracks work.
Loading and unloading a kilnStudio kilns run past 2,000 degrees Fahrenheit. The Clay Hole bisques to cone 05 and glaze fires to cone 5½, which is cone 5 with a twelve minute hold. The hold is what makes a mid-fire glaze finish melting instead of just reaching temperature.
The pottery cone chartWater. A piece that was not bone dry, or that was thick enough to hold moisture in its core, turns that water to steam faster than it can escape and the wall gives way. Thick unwedged lumps of clay and sealed hollow forms with no air hole are the two usual culprits.
Why did my pottery do thatMid-fire and high-fire clay goes slightly soft at peak temperature, so anything unsupported sags. Uneven wall thickness, a wide flat form, or a piece resting on an uneven surface will all pull out of shape. Wide bowls and plates are the usual casualties.
Why did my pottery do thatDunting is a crack that happens from thermal stress during cooling, often with a clean sharp edge that looks like it was cut. It comes from cooling too fast through the point where silica in the clay changes form. It is a kiln schedule problem, not a making problem.
Why did my pottery do thatYes. Refiring is routine for a glaze that came out underfired, and normal for adding a second layer or a decal. Each firing carries a small risk of cracking, and a piece that has already been to temperature several times gets more brittle. Refiring will not fix a crawl or a run.
Reglazing and refiringAt The Clay Hole, bisque firing is free and glaze firing is priced by the volume your piece takes up in the kiln: 5 cents per cubic inch, with a minimum of $4.80 for anything under 125 cubic inches. Volume, not weight, because what a kiln sells is space.
The clay and pottery calculatorsA kiln cookie is a small disc of clay placed under a pot to catch any glaze that runs, so the drip lands on the cookie instead of the shelf. It is cheap insurance on any piece with a running glaze, and it saves a shelf that costs far more than the pot.
Making a glaze catcherBecause the unglazed foot sat directly on the shelf and picked up kiln wash, or because a little glaze ran and had to be ground off. A rough foot is normal and is meant to be smoothed with a rubbing stone or wet sandpaper before the piece goes anywhere near a table.
Fixing fused and sharp potteryOxidation means there is plenty of oxygen in the kiln, which is how every electric kiln fires. Reduction means the atmosphere is starved of oxygen, so the fire pulls it out of the clay and the glaze instead, which changes colors dramatically. Reduction needs a fuel kiln. The studio fires in oxidation.
What a kiln firing actually doesYes, as long as they fire to the same cone. Different bodies in the same kiln is completely normal. What is not fine is a low-fire clay in a mid-fire kiln, which melts, ruins the shelf and can take the kiln with it.
The complete guide to clay bodiesCones sit on the shelf and bend when the right amount of heatwork has been reached, which is the only honest check on whether a firing did what it was supposed to. A controller reports the temperature it thinks it reached. A bent cone reports what the pots actually experienced.
The pottery cone chartDishwashers, microwaves, ovens, chips and stains.
Most well made, fully vitrified stoneware with a well fitting glaze is fine in a dishwasher. The risks are crazed glaze, which lets water into the body, and unglazed feet, which stay damp. Anything with gold or luster on it never goes in, and neither does anything that rattles against something harder.
Food safe, dishwasher safe, what you can claimUsually yes, with one exception that matters: anything containing metal. Gold and platinum luster will arc and damage both the piece and the microwave. Otherwise a fully vitrified glazed piece heats the food rather than itself, though a thick mug will still get hot from the drink inside it.
Living with your potteryOnly if it was made for it, and even then never into a hot oven. Thermal shock is about sudden change, not absolute temperature, so a cold dish into a preheated oven is the thing that cracks. Put the dish in cold, let it heat with the oven, and never set it straight onto a wet surface afterwards.
Living with your potteryA fully vitrified piece with no crazing is usually fine. A piece with crazed glaze or a porous body has water sitting inside it, and water expands as it freezes, which splits the wall from the inside. If it is crazed, keep it out of the freezer.
Living with your potteryThat is crazing, and it is the glaze shrinking more than the clay as the piece cools. It usually looks like a fine web. It can show up straight out of the kiln or months later after a few trips through a dishwasher. It is a glaze fit issue and it cannot be polished out.
Glaze problems, causes and fixesCoffee and tea find their way into crazing lines and into any unglazed porous area, and they darken them over time. On some pieces this reads as character and on others it reads as dirty. A soak in a mild oxygen bleach solution lifts most of it, and a crazed piece will simply stain again.
Living with your potteryYes, and think about drainage before you make it, not after. A pot with no hole needs a layer of gravel and careful watering, or it becomes a swamp. Unglazed stoneware breathes a little, terracotta breathes a lot, and a fully glazed pot breathes not at all.
Making planters for what you are plantingMid-fire stoneware fired properly is close to waterproof even where it is unglazed, so a stoneware vase holds water without a glazed interior. Earthenware does not and needs glaze inside. If a piece sweats or the base feels damp after a few hours, it was underfired or the glaze is crazed.
Living with your potteryWarm water, a soft sponge and ordinary dish soap. Skip the scouring pad on glossy glazes, because it dulls them. Let the unglazed foot dry properly before stacking, and do not leave a piece soaking overnight if it has any crazing.
Living with your potteryNot invisibly, and the honest options are repair or acceptance. Epoxy and mica powder make a visible repaired line in the kintsugi tradition, which turns the break into part of the piece. A repaired piece is decorative from that point on and should not be used for food or drink.
Kintsugi with epoxy and micaEither the body never vitrified, or there is a crack, or the glaze inside is crazed and the water is passing through the clay. Fill it and leave it on a dry paper towel for a few hours: a ring under the base means it is going through the body, a wet line down one side means a crack.
Why did my pottery do thatThrough a Utah winter, only if it is fully vitrified and uncrazed. Any water that gets into the body freezes, expands and breaks the piece from the inside, which is why garden pots crack in the first hard frost rather than in summer. Bring anything precious in.
Living with your potteryThin walls conduct heat quickly and a handle set close to the body picks it up from the wall. It is a design outcome, not a fault. A slightly thicker wall, a handle that stands off the body, and a foot ring that lifts the base all keep a mug comfortable.
Functional pottery is engineeringSay three things: hand wash is safest, no sudden temperature changes, and the unglazed foot will scratch a polished table. That covers almost every way a handmade piece gets damaged. A small card with the piece is worth more than the explanation they will forget.
Living with your potteryHow a shared studio works, and how to get the most out of one.
Open studio is time in the building to work on your own, with the equipment available and no instruction happening. It is where most real progress gets made, because you are repeating things rather than learning them. It is not a class, and the people managing it are not there to teach.
Open studio classes versus open studio timeA class has instructors in the room whose job is to teach, and it uses one of your monthly class credits. Open studio is unstructured time with no instruction. Both give access to the same equipment. The instructed sessions are where to bring questions.
Open studio classes versus open studio timeWork moves from the drop-off table to the kiln, back to the pick-up table, and it appears there when it has been fired. Pieces come out in the order they were loaded, not the order they were made, so two pots made on the same night can come back a week apart.
Pick-up and drop-off tablesTwo weeks from the day the kiln is unloaded. Anything still on the pick-up table after that is forfeit, which sounds harsh until you have seen what a studio looks like when nobody collects anything. Set a reminder the week you glaze something.
Pick-up and drop-off tablesOn the drop-off table, dry, labelled and with the firing paid for. Work left on your own shelf does not get fired, because nobody can tell a finished piece from one you are still working on.
Pick-up and drop-off tablesEverybody does, and usually within three months. The real fix is finishing work and taking it home rather than storing every piece you have ever started. Shelf size is also one of the differences between membership levels.
Running out of shelf spaceYes, with a guest pass. A friend gets a seat in a class with the same instruction you get. There are also whole weeks in the year when bringing friends is free.
Bring all your friends free weekNo. Classes that go unused stay on your account rather than disappearing at the end of the month, which means a busy month does not cost you anything.
Your unused classes never expireYes, for a fee that depends on your level, and the request has to be in before the 24th so it lands before the next renewal. Pausing keeps your spot and your shelf rather than starting over later.
Pausing and cancellingCancel before the 24th and the next month does not bill. There is a page that walks through it, and it does not try to talk you out of it.
How to cancelSometimes. The studio carries a very large range, so most requests are already covered, and there is a published list of what is deliberately not stocked and why. Anything brought in has to be approved first, because a glaze that runs or melts wrong damages shared kiln shelves.
Glazes we do not carryThere is. Mud is a miniature Australian Labradoodle and he has his own page, his own opinions about who is allowed to leave, and a habit of appearing the moment anyone opens a snack.
Meet MudPractice, records, photos, selling, and comparison.
Repeat one form instead of making a different thing every session. Ten cylinders in a row teaches more than ten different pots, because the only variable left is you. Measure them, keep the best, reclaim the rest, and do it again next week.
The wheel practice planYes, and not just the good ones. A photo of every finished piece next to a note of the clay and the glaze is the single most useful record a potter can keep, because glaze results are impossible to remember accurately six months later.
Photographing your potteryStart from what the piece actually costs you to make, including clay, firing and the pieces that did not survive, then decide what your time is worth. Most beginners price from what they think people will pay, discover they are working for nothing, and quit selling.
What a pot actually costs you to makeCraft fairs and markets, galleries, your own online shop, and word of mouth, roughly in that order of difficulty to start. Each one wants a different kind of work and a different volume. Selling a few pieces to friends is not the same business as supplying a gallery.
How to start selling your potteryNot to make good work, but you will want one the first time somebody asks who made a piece. A stamp is the easiest version and takes an afternoon to carve. Start using it early, because unsigned work is impossible to attribute later.
The history and tradition of maker’s marksWrite it down on the day, on paper or on your phone, tied to a photo of the piece. Glaze names blur together, combinations are impossible to reconstruct, and a piece you love becomes unrepeatable without a record.
Logging your pottery and glazesA test tile is a small piece of your clay carrying a glaze, fired the way your work is fired, so you can see the real result before committing a pot to it. Making a set of them is the least glamorous and most valuable afternoon a potter can spend.
Making and dialing in test tilesIt depends on what your time is worth and how much you throw. Reclaim is genuinely free clay, and it is also a messy hour of work for a modest amount of it. Potters who throw a lot reclaim. Potters who make a few pieces a month usually should not bother.
Reclaiming your clay, worth it or notYou do not, entirely. What helps is comparing your work to your own work from six months ago, which is the only comparison with any information in it. Keep one early piece on a shelf where you can see it.
Comparison is the thief of joyNot until you know what you actually make. A wheel is the cheap part. The kiln, the electrical work, the ventilation and the space are where the real money goes, and most home setups sit unused because firing one piece at a time is miserable. The full cost comparison is worth reading first.
How much does pottery costNothing matches that. Try a shorter word, or clear the search and pick a topic instead. The fault finder covers symptoms this page does not.
Forty five things that go wrong, sorted by the stage they happen at, with what caused each one. And two hundred and fifty four terms in plain English for the words nobody explains.
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