How to Throw Off the Hump for Fast, Matching Cups
Throwing off the hump is how production potters make a dozen cups in the time it takes most beginners to center one ball. You center one large mound of clay, throw a small pot from the top, cut it off, and repeat with the same mound.
It saves time, helps you practice centering once and makes matching sets easier. It also takes a bit of getting used to.
Why it works
- You center only once for many pots.
- Each pot comes from the same clay, so the walls behave similarly.
- The mound is a natural gauge, so repeating heights is easier.
- You build rhythm, which improves your speed and consistency.
Read our lessons on what throwing off the hump is and throwing and cutting off for photos of each stage.
What you need
- A wheel and a bat or board
- A bucket of water and a sponge
- A needle tool
- A wire or twisted cord for cutting
- A rib and calipers or a height stick
- Clay: for six small cups, around 2 to 2.5 kg (about 5 pounds) for the hump, depending on cup size
- A board to place finished pieces on
If you are unsure how much clay each cup needs, try the clay weight estimator.
Step by step
1. Center a big mound. Center the whole hump firmly. Our guide to centering clay helps if this part wobbles. Cone it up slightly so the top is a bit narrower than the base.
2. Mark your first section. With a needle tool, mark where each cup will begin. Leave a small collar of clay at the bottom of each section, which will become the foot.
3. Open the top. Open a small hole in the top section, as you would for a cup. Keep the base of the hump wide and strong.
4. Throw the cup. Pull up the walls just like a small cylinder. Keep an eye on the height with a stick or caliper so each cup matches. See throwing a consistent cylinder.
5. Finish the rim and define the base. Compress the rim, then use a rib or tool to make a small groove below the cup. This tells you where to cut and gives the cup a neat foot.
6. Cut off. Hold the wire taut, slide it under the cup at a slight angle and cut cleanly. Let the wheel spin slowly while you cut.
7. Remove the cup. Slide it off with your hands or a board, and place it to dry.
8. Repeat. Re-center the top of the hump quickly and throw the next one.
Common problems
- The hump wobbles. Re-center before each cup.
- Cups differ in height. Use a height stick as a guide.
- Wire drags and distorts the base. Use a taut wire and a clean, even motion.
- Clay dries out. Keep the hump damp with a sponge, but don't let water pool.
- Cups collapse. Don't pull too thin near the base.
Trimming and drying
Cups thrown off the hump often have a small foot that needs trimming. Dry them slowly on a board and trim at leather hard. See how to trim a foot ring.
Practice drills
Start with three cups, then six. Our practice exercises, such as three cups off the hump, build the skills step by step.
Record the clay weight, the number of cups and the dimensions. Logging weights makes it much easier to repeat a set, and Claybook helps you keep those numbers.