A tool holder includes a main body defining a mounting end and a receiving end, the mounting end positioned opposite from the receiving end, the main body defining a main body bore extending into the receiving end toward the mounting end; an extension defining a tool head attached to a rod, the tool head defining a tool head end opposite from the rod, a tool holder length defined between the mounting end and the tool head end, the tool head configured to receive at least one cutting tool, the rod received within the main body bore; and a locking mechanism engaging the extension and the main body in a locked position, the locking mechanism being disengaged from either the main body or the extension in an unlocked position, the locking mechanism being selectively positionable about and between the locked position and the unlocked position.