Crank is the trade name for a heavily grogged, very open body built to survive size and thermal stress. It is what large sculpture, garden pots, kiln furniture and anything with heavy sections is made from, and it is deliberately coarse: the grit is the reason it works.
What crank is for
Anything big. A large form has thick sections, long drying times and considerable stress between its parts, and a smooth body will crack under all three. Crank's heavy grog content reduces shrinkage, opens paths for water to escape and gives the wet clay enough structure to stand up while it is being built, which is what lets a piece grow beyond the size a fine body will hold.
How it feels, honestly
Coarse. Crank is hard on hands over a long session and it will not take crisp detail, which is why it is a hand-building and sculpture clay rather than a throwing one. Some potters throw it for large forms and accept the abrasion; most use it where its structure is the point and use something smoother where the surface is.
Firing and thermal tolerance
An open, grogged body handles heating and cooling better than a dense one, which is why crank is also the body used for raku-adjacent work, for pieces fired repeatedly and for anything that will live outdoors through a winter. Frost resistance comes from firing high enough that water cannot get in, so the top of the body's range is the right target for garden work.
Where it sits on price
Crank bodies are usually priced in line with other stoneware rather than at a premium: CTM lists craft crank at similar money to its plain stoneware rows, and Bath Potters carries several crank bodies among its stoneware listings. Because crank work tends to be large, the quantity ladder matters more here than the headline: buying several bags at once is where the real saving is.
Questions people ask about crank clay
What is crank clay used for?
Large hand-built and sculptural work, garden pots and anything with heavy sections, where shrinkage and thermal stress would crack a smooth body.
Can you throw crank?
You can, and it is abrasive and holds little detail. It is normally chosen for hand building rather than the wheel.
Is crank frost proof?
A crank body fired to the top of its range and properly vitrified will survive outdoors; an underfired one will absorb water and break in a frost.