I wanted a coffee table, an ottoman and a chair… So I decided to make one that is all 3. Here we have it in ottoman format. It then converts into a coffee table once the cushion is replaced.
We then remove a board using a dowl rod peg that was drilled and hammer in. We take the seat back and place it in a slot at the inside back. Then we place the additional board and the board with the peg in it at the seat. We then apply the cushion and seat back and we have a chair.
Lets dive into the build and design process. I want to lead with I am novice wood worker. So we start out with 2 x 12 at the lengths and quantities listed on this slide and make a box by screwing in at the locations listed here in yellow I pre drilled a ½ inch hole so I could cover the screws with a ½ inch dowl rod plug.
Next we place 2 x 4 x 6 inch board in each corner and screw in place.
Then we place a 2x4 that is 24 inch or the inner dimension of the box ontop of these supports. This setup allows the weight to be transferred directly to the ground rather than twisting the 2 x 4 or causing a moment.
To insure this outside 2 x 12 box did not sway I added 4 fasteners on the front and back. Probably overkill but I can afford 8 screws in my budget.
Next we need to make the mounting hole for the chair back I did this by placing 2 2x4 x 7 and 5/8 inch boards in the back corners butted up to the 2x4’s from the previous step.
Then screwing on a board that fits between the 2x4’s from the last step that spans the entire distance. I places a metal plate left over from an electrical box to space this. Which makes it so we do not have to sand the chair back post.
Now lets move onto the seat surface slash chair back cut list. We will be using 2 x10’s 2 x 6’s for the seat surface. The math works out to be 26 inches but dimensions construction lumber is not the actual size and it works out by design to be about 24 inches. You will also need another board that will be used when in chair mode for the seat. I have a 2x12x24 inch board scrap piece that I used. You may need to make this board slightly smaller to maneuver in and out of the box storage.

Now we will need to attach a post to the back of the chair. I used a 2x6 which will fit with some clearance in the chair back post hole on either side. The chair post is 19 inches long but you could probably vary it slightly.
Note be mindful of the 2x12 at the front and the 2x4 at the back which has the potential of interference when mounting your chair back post. I placed the boards ontop of the box to screw the post in place this worked wonderfully because I could see where the interference would be.
To finish this off I screwed on a stopper block that rest on the back 2x12. The length isn’t that important as long as you don’t interfere with anything.
You could probably get away with putting a stop block in the chair back post hole. Which might be a better design.

Final thoughts. I am 6 feet tall and this seats me comfortably I was a little worried the chair back would be to short. Being the back is at close to a 90 it forces you to sit with better poster and have been told by multiply people it is pretty comfortable. All in all I am in this project about $50 for the construction materials. Not counting cushion.



Disclaimer These videos are intended for educational purposes only (students trying to pass a class) If you design or build something based off of these videos you do so at your own risk. I am not a professional engineer and this should not be considered engineering advice. Consult an engineer if you feel you may put someone at risk.