Abstract: Apparatus for cutting a plurality of generally parallel channels such as the steps and risers in a stringer for a staircase or the shelves in a book case which includes an elongated first, second, third and fourth members. Each member has first and second ends. The second end of the first member is pivotally connected to the first end of the second member, the second end of the second member is pivotally connected to the first end of the third member, the second end of the third member is pivotally connected to the first end of the fourth member and the second end of the fourth member is pivotally connected to the first end of the first member. The first, second, third and fourth members define a parallelogram with pivotable connections at the respective points of connection of the respective members. The angles intermediate pivotally connected members are adjustable by relative pivotable motion between the respective pivotally connected members.