Step 3: Cut and laminate
I laminated the both sides separately . As I'm using steel for the connections I can laminate in 2 halves and dont have to do them in one go.
I used 5 layers of 4mm ply and that got me to 24mm total thickness. I used PVA white glue as it's cheap and I had some. The glue was painted on thick till the complete surface was covered and then I just clamped them on one by one. After about an hour each time I just stuck some screws in from the back to hold the last piece in place, took the clamps off and glued another one on.
The right way would probably be to wait a day between layers. Its amazing but after the 3rd one I released all the clamps just to see what would happen and it kept its shape. This is the first time I bent wood and although I know it works it still blew me away.
Its all drying in the shed overnight.