Slip, Slurry & Score
The Essential Language of Handbuilding Clay**
If you’re new to handbuilding or working with one of the Throw & Fire clay kits, you’ve probably heard the phrase “slip and score” more than once. It’s the secret handshake of the pottery world — a simple technique that keeps your clay pieces from falling apart later.
But what exactly is slip?
Why do we score the clay?
And what’s the difference between slip, slurry, and all the other clay terms floating around?
Let’s break it down.
What Is Slip?
Slip is simply clay + water, blended into a smooth, creamy consistency.
Think of it like pottery glue — because that’s truly what it is.
Slip can be:
- Thick like pudding
- Creamy like paint
- Thin like heavy cream
The thicker the slip, the stronger the bond.
Potters keep slip in everything from yogurt cups to mason jars to fancy slip containers — it’s a studio essential.
What Is Slurry?
Slip and slurry are often used interchangeably, but there is a difference:
Slip
Prepared, smooth, intentional, and often stored for later use.
Slurry
The watery clay that forms naturally in your bucket, on your wheel tray, or after sponging your hands — thinner, more inconsistent, and often filled with tiny clay bits.
Both can work in a pinch, but slip gives you a stronger join.
What Does It Mean to Score Clay?
Scoring means scratching the surface of the clay where you want to join two pieces.
Think of it like roughing up a surface before gluing it.
You can use:
- A needle tool
- A fork
- A serrated rib
- A scoring tool
- Even a stiff toothbrush in a pinch
You’re creating tiny grooves for the slip to fill — and once the clay is fired, those grooves lock together like Velcro.
So Why Do We “Slip and Score”?
Because clay shrinks as it dries — and smooth surfaces don’t bond well.
Slip and score creates a mechanical lock and a chemical bond.
Without it?
- Handles fall off
- Attachments crack
- Coils separate
- Projects break during drying
- Glaze firing becomes a heartbreak waiting to happen
Slip + score = structure, strength, and happy potters.
The Basic Slip & Score Steps
Here’s the simple method used in beginner classes and pro studios alike:
1. Score both surfaces
Scratch lines into both areas you want to join.
2. Add slip
Paint, dab, or smear slip into the scored lines.
3. Press pieces together
Press firmly until the seam feels solid.
4. Blend the seam
Use a finger, wooden tool, or soft rib to smooth the outside.
5. Reinforce if needed
For handles or heavier joins, add a small coil and blend it in.
That’s all there is to it — but it works every time.
Common Myths About Slip & Score
“You don’t need to slip and score if the clay is fresh.”
Not true. Even fresh clay needs a mechanical bond.
“Water works just as well as slip.”
Water alone is too weak — it creates slickness, not structure.
“My piece looks stuck together; it must be fine.”
Looks can be deceiving! Weak joins often don’t fail until after the bisque firing.
Your Clay Project’s Best Friend
Slip and score may seem like a small step, but it’s one of the most important skills in handbuilding. It ensures your projects stay together from the moment you build them until the moment you bring them home from the studio.
Once you’ve mastered it, you’ve unlocked one of the true fundamentals of ceramics — and every mug, sculpture, and bowl you build will thank you.