How to Build Arms On a Chair

Position a 1- by 2- by 12-inch board with its end against the backrest of the chair and its largest side facing sideways. Hold the board at the desired height for the armrest. Mark the location of the board on the backrest of the chair.

Drill two holes through the backrest of the chair and into this armrest board. Set 3-inch wood screws in each hole and tighten them completely to firmly attach the board to the chair. Repeat to install another armrest board on the other side of the chair.

Position a 1- by 2- by 8-inch board perpendicular to the arm rest board and with its largest side facing sideways. Set one end of this board against the bottom of the armrest board, all the way at the end of the board. Set the other end of this board, which is the arm rest support board, against the side of the chair seat, so that the side of the arm rest support board is flush against the side of the chair seat.

Drill two holes through the arm rest support board and into the chair seat, or drill out from within the chair if possible. Set 3-inch wood screws in the holes and tighten them completely to fasten the arm rest support board to the chair.

Readjust the joint between the arm rest board and the arm rest support board, and drill two holes down through the top of the arm rest board and into the end of the arm rest support board. Set 3-inch wood screws in the holes and tighten them securely to attach the boards together. Repeat to fasten another arm rest support board to the other side of the chair.