How to Apply Glaze to Pottery Without Runs
Glazing is one of those stages in pottery that looks deceptively simple. You slap on some colour, fire it up, and out comes something beautiful – right? Well, not always. Runs, drips, bare patches, and pooling glaze are among the most common frustrations for beginners, and they can turn a piece you’ve spent hours making into a disappointment. The good news is that avoiding these problems is entirely learnable. With the right preparation, the right tools, and a bit of patience, you can achieve clean, even, professional-looking results from your very first proper glazing session.
This guide will walk you through everything you need to know, from choosing and mixing your glaze correctly through to the moment you load your kiln. Whether you’re working from a home studio, attending a class at a local pottery centre, or just starting out with a small test kiln in your garage, the principles here apply across the board.
Understanding What Glaze Actually Is
Before you can control glaze, it helps to understand what it’s made of. At its core, glaze is a mixture of minerals and metalite oxides suspended in water. When fired in a kiln, these materials melt, fuse, and form a glassy coating on the surface of your clay. That coating can be matte or shiny, opaque or translucent, smooth or textured – and the outcome depends on the recipe, the firing temperature, and, crucially, how well you applied it in the first place.
Most beginners start with commercial ready-mixed glazes, which you can buy from UK suppliers such as Bath Potters’ Supplies in Bath, Potterycraft based in Birmingham, or Scarva Pottery Supplies in Northern Ireland. These are reliable and consistent, which makes them ideal for learning. Once you’re comfortable with application, you can branch out into mixing your own glazes from raw materials – but that’s a journey for another day.
The most important property to understand right now is viscosity: how thick or thin your glaze is. Too thin and it won’t give enough coverage, leaving you with a pale, washed-out result or bare patches after firing. Too thick and it won’t dry evenly, leading to drips and crawling. Getting the consistency right is the single most impactful thing you can do before you even pick up a brush.
Preparing Your Bisqueware Properly
Glaze won’t adhere well to dirty clay. If your bisque-fired piece has dust, grease from your hands, or any residue on it, the glaze will resist in those areas, often pulling away or blistering during firing. This is one of the main causes of crawling – where glaze beads up and retreats from the surface like water on a waxed car bonnet.
The fix is straightforward: clean your bisqueware before you glaze it. Wipe the piece down with a clean, barely damp sponge, and then let it dry completely. Some potters lightly sand the surface with a fine grit sanding pad if there are sharp edges or rough spots, since these can cause the glaze to settle unevenly. Once the piece is clean, handle it as little as possible – and when you do pick it up, hold it by areas that won’t show, or wear clean latex or nitrile gloves.
It’s also worth checking for any hairline cracks at this stage. Glaze can accentuate cracks rather than hide them, and a cracked piece that goes into a kiln can break apart entirely, potentially damaging other work in the same firing.
Mixing and Testing Your Glaze
If you’re using a commercial glaze that’s been sitting in a bucket for a while, it will have settled. You’ll often find a thick, clay-like layer at the bottom and watery liquid at the top. Do not just pour off the water. Instead, stir thoroughly – a drill with a paint mixing attachment works brilliantly for larger quantities – until the glaze is completely uniform. A wooden spoon or a robust palette knife will do the job for smaller amounts.
Once mixed, test the consistency. The traditional method is to dip a clean finger or a strip of bisqueware into the glaze and pull it out. You’re looking for an even coating about the thickness of a layer of cream. It should cling to the surface without dripping off straight away, but it also shouldn’t look lumpy or gloopy. Many experienced potters use a pint measure to check the specific gravity of a glaze – this is the weight of a set volume of glaze compared to the weight of the same volume of water. Most stoneware glazes work well at around 1.4-1.5 specific gravity, but check the guidance from your supplier as earthenware and porcelain glazes can differ.
Always, always test new glazes on a small tile before committing to a finished piece. Fire the tile in the same kiln, at the same temperature, that you’ll use for your actual work. Glazes can look completely different after firing compared to their unfired state, and what appears to be a pale, unremarkable grey can emerge from the kiln as a deep, rich celadon.
The Main Application Methods
There are several ways to apply glaze, and each has its place depending on the piece you’re working on and the effect you want to achieve.
Dipping
Dipping is the method most commonly used in studio pottery for good reason – it’s fast, it produces even coverage, and once you get the hang of it, it’s consistent. You simply hold the piece and submerge it in a bucket of glaze, hold it there for a second or two, then lift it out and let it drain. The tricky part is holding the piece without leaving fingerprints or bare patches. Tongs are your friend here, and you can buy pottery tongs from most UK ceramic suppliers. After dipping, you can touch up any marks from the tongs with a small brush dipped in glaze.
The inside of pots is usually glazed separately before the outside, using a method called pouring: tip glaze into the pot, swirl it around to coat the interior evenly, then pour it back out into the bucket. Let the inside dry before you dip the exterior, otherwise the layers will become too thick and you risk runs.
Brushing
Brushing is the most accessible method for beginners and requires no special equipment beyond a decent brush. It gives you excellent control and is ideal for applying decoration or for pieces that are too small or too awkward to dip. However, it is the method most prone to uneven coverage if you rush it. Glaze applied by brush needs multiple coats – typically three or four – and each coat must dry before the next goes on.
Use a wide, soft brush for larger areas, working in smooth, overlapping strokes. Avoid going back over areas you’ve just brushed, as this can lift the already-drying layer underneath and create bald patches or streaks. Some potters find that rotating the piece on a banding wheel while brushing helps to keep the coverage consistent around the sides of a pot or vase.
Pouring
Pouring is useful when you want to cover large, flat surfaces or when you want to create intentional drip effects in a controlled way. Holding the piece over your glaze bucket, pour glaze steadily over the surface and rotate the piece as you go. The trick is to work quickly and confidently. Hesitation leads to uneven patches and unwanted drips that dry in place. Like dipping, pouring requires good preparation and a steady hand.
Spraying
Spraying uses a spray gun and compressor to apply an atomised mist of glaze, producing incredibly smooth, even coverage. It’s favoured in professional studios but requires proper ventilation and respiratory protection – glaze dust is hazardous to inhale. In the UK, if you’re working in a shared or commercial space, you should be aware of COSHH (Control of Substances Hazardous to Health) regulations, which require risk assessments for any process involving hazardous materials including glaze dusts and fumes. For most home beginners, spraying is overkill, but it’s worth knowing about for when you progress.
Step-by-Step: Applying Glaze by Dipping (for a Simple Bowl or Mug)
- Clean and dry your bisqueware. Wipe with a barely damp sponge, then leave to dry thoroughly – at least 30 minutes, longer in damp weather.
- Mix your glaze bucket thoroughly. Stir until there is no sediment left on the bottom and the consistency is even throughout.
- Check the consistency. Dip a test strip or your finger. The glaze should coat smoothly without dripping heavily. Adjust with small amounts of water if too thick, or stir and allow to settle if too thin.
- Wax the foot ring. Apply wax resist (available from most ceramic suppliers) to the bottom of the piece – the foot ring and any area that will sit directly on the kiln shelf. Glaze on the base will fuse the pot to the shelf during firing, ruining both. Leave the wax to dry for a few minutes before proceeding.
- Glaze the interior first. For a bowl, pour a generous amount of glaze inside, rotate to coat evenly, then pour back out. For a mug, do the same. Allow to dry completely – the surface should appear powdery and dry to the touch.
- Dip the exterior. Hold the piece with tongs or by the foot ring, submerge it in the glaze bucket upside down to coat the exterior, hold for one to two seconds, then lift and allow to drain over the bucket. Gently rotate the piece as you lift to avoid drips collecting in one spot.
- Set it down carefully on a bat or board to dry. Don’t place it on newspaper – the ink can transfer to wet glaze.
- Touch up tong marks or bare patches with a small brush dipped in glaze once the surface has dried a little.
- Check the base. Make sure there is no glaze on the
base or foot ring — any glaze left there will fuse the piece to the kiln shelf during firing, which is both damaging to the kiln furniture and potentially ruinous to your work. Run your finger around the base and wipe away any residue with a damp sponge.
Once the glaze has dried to a matte, chalky surface — usually within fifteen to thirty minutes depending on the thickness of application and the absorbency of the bisqueware — inspect the piece under a good light. Look at it from a low angle to catch any thin patches, uneven coverage, or places where the glaze has beaded rather than adhered properly. Thin areas tend to fire out pale or rough, whilst overly thick patches are the most likely source of runs. If you spot a thick drip or ridge, wait until the glaze is fully dry and then carefully sand it back with fine-grit sandpaper or a slightly damp finger. Work gently — bisqueware is fragile and the dried glaze layer, though it looks solid, brushes away easily.
Before loading the piece into the kiln, give the base one final wipe with a clean, barely damp sponge. Check that wax resist, if you applied it, has done its job and that the foot ring is clean and dry. Keep glazed pieces upright in the kiln and ensure they are not touching one another, as glaze that runs even slightly during the firing can bond two pieces together permanently. Using kiln wash on your shelves adds an extra layer of protection should a small run occur despite your best efforts.
Achieving a clean, even glaze coat takes practice, but the principles remain consistent: well-prepared bisqueware, glaze mixed to the right consistency, confident and deliberate application, and careful checking before the kiln is loaded. Each method — brushing, pouring, dipping — has its place depending on the form and the finish you are after. Over time you will develop a feel for how your particular glazes behave, how thickly they need to be applied, and where on a given shape they are most likely to cause trouble. Keep notes on your results, adjust your approach methodically, and the incidence of unwanted runs will reduce with each firing.
