A handy and economical tip I’ve picked up from my community of potters is how to have a nearly endless supply of inexpensive throwing sponges. Simply cut up an Armaly ProPlus polyurethane sponge—the large, yellow kind found in a hardware store’s grout and flooring aisle. They’re made of a durable fiber that lasts a surprisingly long time. One sponge, which costs around $2.50 (a contractor pack of 6 costs $12.50), can be cut down to make 12 small throwing sponges ($0.17 each).
The easiest way to cut them is to use a sharp chef’s knife; however, a box cutter or scissors will also work. Using a Sharpie, trace cutting lines onto the sponge, dividing the face into sixths, then mark a horizontal line around the side of the sponge. The first cuts should be into the face of the sponge to cut out six pieces (1), then each piece can be tilted up to cut it in half horizontally (2).
You will end up with 4 square sponges and 8 with one rounded corner (3). I like having sponges with 90° angles, which can be used to get into hard-to-reach places for cleaning and drying. It’s easy to round off the corners if you prefer round sponges.
As an extra bonus, it’s simple to make your own sponge on a stick using a wooden dowel, a rubber band, and one of your new sponges. Hold one corner of a sponge across the tip of a dowel and repeatedly loop the rubber band around the sponge’s base (4).