Math for Potters

13. Math for Potters

In keeping with the liberal arts aspects of a career in ceramics I gave my students a variety of extra credit math assignments. These problems were not whimsical. Each of them came from my own experiences as a studio potter.
The first deals with the time and space constraints of kiln size, firing schedules, and event deadlines. For example, “Today is the first of February and you have a Fair on the 23rd. Any pots you throw today won’t be dry enough to bisque until the 5th. Your kiln holds 24 of your standard sized mugs and each mug will need to be fired twice (bisque and glaze). The firing cycle for your kiln, loading to unloading, is 24 hours. You buy your clay wet in fifty pound boxes, two bags of 25 lbs. each. You get 15 mugs from each 25 lb. bag of clay.
“Presuming no breakage, how many new mugs will you have for the Fair? Also, how much clay do you need to buy if you have none in your studio to begin with? Bonus question: If you make 32 mugs per day, on what day will you be done throwing mugs for this Fair?”
The second problem relates to mixing glazes. Glaze recipes are written in grams but ceramic supply houses sell those ingredients by the pound. Using a glaze recipe chosen at random from those used by the students, the questions is, “How many pounds of each ingredient do you need to buy to make a full 10,000 gram batch of that glaze?” [It takes 454.5 grams to make a pound.] Most students, raised on fill-in-the-dot multiple choice tests, will tend to round off their calculations. (Sometimes in the wrong direction.) The universe is not so convenient as to provide round numbers for its real life problems.
Neither of these problems involves the calculus of determining complex volumes or the simple fingers-and-toes counting of a checking account deposit slip. Certainly a wide variety of ceramics math problems are available and students need to learn to think them through. The point is to demonstrate to the students the diverse complexities of ceramics and the unending need to use their brains fully. Studying ceramics does not free us from the need to read and write and use mathematics. It gives us the opportunity to use all those skills in a worthy and noble cause.
So, if a train full of potters leaves Chicago travelling eastward at sixty miles per hour… how much fun will they have at the clay conference?