The chair frame was dismantled and the metal frame and fabric seat set aside. The wooden frame was adapted by removing approximately 6″ (150mm) from the back edge of the armrest and base on each side. The cross members were shortened so that the overall width of the frame, when re-assembled, is approximately 18″ (450mm). I drilled the ends of the cross to allow me to re-use the original dowel fittings which were glued in place but I used new 4″ (100mm) screws to strengthen the joint between the cross members and the upright part of the frame. The cross member at the base of the frame was set back so that, in the new seating position, it did not interfere with the feet of the user. (Cutting the ends of the frame as described above removes the fixing positions and the redundant holes as well as improving the proportion and performance of the chair.) The seat was manufactured from a piece of 3/4″ (18mm) MDF but any board material would work. Mine is finished in matt black (blackboard) paint. I drilled and countersunk three 11/2″ (38mm) screws on each site of the seat to give a firm fixing to the frame – glue could be added for further strength if required.