pounding block

A pounding block is a dense, smooth-faced tool used to flatten and set seams in fabric or leather by striking the seam against a solid backing surface. The block itself absorbs and distributes the impact of a hammer or mallet blow, pressing the seam flat while the hard surface beneath prevents the material from bouncing. In tailoring, garment manufacturing, and leatherwork, this is essential for creating crisp, permanent creases and closing gaps between stitched edges.

Blocks are typically cast from iron or steel, ranging from 2 to 5 pounds in weight, with one or more flat faces that are polished smooth. Some blocks feature a curved surface on one end for rounded seams or hems. The handle may be integrated as a metal or wooden grip, or the block may be used freestanding. Brass and aluminum blocks exist for delicate fabrics where steel might damage or mark the material.

The operator places the seam flat against a sturdy metal or wooden anvil or pressing surface, positions the pounding block face-down over the seam, and strikes the block with a hammer. The strike must be controlled and evenly distributed to avoid creating dents or bruises in the fabric. On synthetic or heat-sensitive materials, repeated pounding can generate enough friction to damage fibers or alter the texture. Improper angle or force can also bend needle shafts left in the seam or tear delicate fabrics.

The tool's name is literal: you pound the block onto the seam. It sits alongside other pressing equipment in a garment factory or tailor's shop, distinguished from a sleeve board or pressing ham by being a solid block rather than a padded form, and used with percussion rather than steam or heat. Historical blocks were sometimes made from hardwood, but metal has dominated industrial use since the late 19th century because it withstands repeated striking and does not absorb moisture.