United Brotherhood of Carpenters & Joiners of America Banner, Portland, Maine, ca. 1910. Maine State Museum, 2015.30.1.
Like the ship carpenter's banner, this banner's center motif has a shield with a square and compass. The corner tools are a drill, a plane, a chisel and a hammer, typical tools of carpenters and joiners. A joiner is a tradesman who joins pieces of wood together. Their work often includes decorative finish work on houses, ships, or furniture.
By 1910, the United Brotherhood of Carpenters & Joiners was the largest trade union in America. The organization worked to discourage piecework, the partial assembly of goods by unskilled laborers, and advocated for the apprenticeship system.