The copper is only about 1mm thick so it needed a support to hold it up and also attach it to the frame. I got some 18mm (3/4 inch) plywood and cut a piece 1000mm x 550mm and cut some strips about 75mm (3inch) wide. I glued and screwed these strips around the edge of the top to make the top seem thicker.
The hammered effect in the copper is simple to achieve, it just takes a lot of stamina in your arm!! You will need a ball pein hammer https://en.wikipedia.org/wiki/Ball-peen_hammer to get this effect and it is simply a matter of hammering the copper! You will get a feel of how hard you need to hit it after a few goes.
Attaching the copper to the plywood.
After my arm had recovered from all the hammering I stuck the copper to the plywood with some strong silicone. I used Tec7 . After applying the silicone I added some heavy weights to the plywood and copper to ensure any lumps were flattened out and that they bonded together correctly.
Folding the corners:
As I said earlier copper is a soft metal and pliable. The corners need to be cut to fold it properly so I set out some pencil lines of where to cut (see pics and video) and cut these with the tin snips. I then folded it as far as I could by hand and then using the flat side of the ball pien hammer hammered the copper around the corners as neat as possible. When I folded it around the bottom side I used some nails to hold the copper in place.
I used a compound paste to clean the copper one last time. In the end I did not put any finish onto the copper as I want it to darken up and colour over time. To keep the shiny polished look a lacquer can be added .