Height Adjustable Bar Stool

This adjustable height bar stool is the result of my search for a chair I could use in my shop at the computer an d the cnc. Both surfaces are way higher than any desktop so I needed a bar stool of a kind. As I wasn't sure on the exact height I came up with simple method of adjusting the seat height: You just tilt the seat a little and insert it into the appropriate recess. It will fit into the curved 'ladder' of the legs.

After some iterations of cad modeling, I did some first test cuts on the cnc. Some further improvements and a full fledged prototype out of cheap pinewood, showed that the idea was working in general, but the soft wood did bend to much on the seat and the back rest. A friend of mine did a prototype out of baltic birch plywood and this worked out just great.

Other than many of my designs I joined the parts using screws and tenons. I added some marks in the drawing to predrill holes with the cnc. After assembly I drilled the holes into the counterparts.