What is the purpose of a tuck-pointer's grinder?

The purpose of a tuck-pointer's grinder is primarily to cut damaged joints in masonry work. This tool is specifically designed to remove old or deteriorated mortar from the joints between bricks or stones, allowing for the replacement or repair of the mortar with new material. Properly cutting out damaged joints is crucial to maintaining the structural integrity and aesthetic appeal of masonry structures. The grinder helps ensure that the joint is clean and well-prepared for the new mortar, which leads to better adhesion and a longer-lasting repair.

In contrast, the other options do not align with the primary function of a tuck-pointer's grinder. Cutting tile requires a different type of cutting tool designed for tile materials, finishing concrete edges involves tools like edgers or trowels, and mixing mortar is done with tools such as mixers or hoes, not with a grinder.