A cup with a handle, a teapot with a spout or a lid with extra decoration… As a ceramicist, you often have to join two pieces of clay together. This can be a little nerve-wracking because there is no guarantee that they will still form a single piece after their trip to the kiln.
Fortunately, there is a technique you can use to minimise the risk: the ‘slip and score’ method. We will explain how to do this step by step.
Step 1: Check both parts
Joining different pieces of clay together is easiest when the clay is still wet. However, you have to be careful not to deform the two parts accidentally.
This is why many potters let the clay dry first, until it’s leather-hard. The ideal consistency is when the clay no longer deforms when you pick it up, but you can still work with it if you try hard enough.
The most important thing is to make sure that both pieces of clay are the same level of dryness. Otherwise, one part will dry faster than the other. This can easily lead to cracks.
Step 2: Prepare both parts
Decide exactly where you want to attach the two parts to each other. Check that everything fits correctly, then make a small mark where the parts will meet.
Make a few parallel scratches on the marks using a sharp instrument or a serrated knife. Repeat this step for the other part.
Step 3: Add clay slip
Clay slip acts as a glue, sticking different clay parts together. The consistency of the clay slip needed depends on your project.
If the clay is still damp, use a fairly liquid clay slip. For drier clay, use a slightly thicker slip. In that case, apply the slip to both parts. This will create a stronger bond.
Step 4: Join the pieces together.
Bring the pieces of clay together. Some excess clay slip may appear around the edges. Simply smooth this out and mix it with the rest of the clay. If necessary, use a damp sponge to do this.
To further strengthen the joint, roll a small amount of clay into a coil and add it around the joint. Make sure you smooth the coil and mix it with the rest of the clay.
