A typical ice block used for ice sculpture is about 20" wide x 40" tall x 10" deep and weighs in at nearly 300 pounds. You usually let those sit for about 1 to 2 hours before carving. Of course, the smaller the block the less time it is going to take to temper. A good rule of thumb is to carve when the ice stops looking cloudy on the outside due to freezing condensation on the outside of the ice. Melting ice is easier to work with then stuff right out of the freezer.