Understanding the wheel's speed and proper hand positioning is essential for efficient and safe pottery centring.
Speed of the Wheel:
Optimal Speed: The wheel should be spun at a fast pace, but not at its maximum speed. A very high speed is seldom necessary and can be counterproductive. A quick rotation ensures that any adjustments you make with your hands affect the entire piece of clay almost instantly. The goal is for the wheel to rotate several times every second.
Avoid Slow Speeds: Centering at a slow pace can prolong the process unnecessarily, especially when producing multiple items like bowls or mugs. If the wheel spins too slowly, you'll have to maintain pressure or positioning longer to ensure the adjustments are applied evenly across the clay, which can be inefficient.
Hand Positioning:
Avoiding Skin Irritation: Beginners often press the palm or side of their hand too firmly against the metal wheel head, which can wear away the skin and cause discomfort. Avoid pushing your fingers or any part of your hand directly down onto the metal. If you notice metal residue on your skin or feel excessive friction, adjust your hand positioning.
Maintaining a Slip Barrier: Ideally, maintain a thin layer of slip (watery clay) between your hand and the wheel to reduce friction. This layer naturally forms as you centre the clay. If you hear a grinding noise or feel friction, slightly lift your hand, so it's just above the spinning metal, maintaining the slip barrier.
Pinching Fingers and Stability:
Focusing on Finger Tips: Rather than watching the clay, observe your fingertips. If the clay is off-centre, your fingertips will wobble along with it. To correct any wobble, squeeze your fingertips inward against the clay, focusing on keeping them steady and unwavering.
Ensuring Centered Clay: If your fingertips are stable and not wobbling, the clay beneath them is likely well-centred. For re-centring, lean the palm and ball of your thumb of your left hand into the clay, pushing forwards, then stabilize any wobbling digits until they're completely still. Follow this by compressing down with your right hand from the top.