I collected my aluminium sheets on Wednesday (April 28) and have been working on them since.
I’ve glued the first part of a two piece joint strip to the central stringer and as you can see here clamped the edge of the aluminium to it. Then I drilled a row of holes (150mm spacing) along that edge and screwed it down temporarily.
With the edge secured and a clamp holding the other side of the sheet I hoisted the whole thing up so I could draw around the frame. The aluminium isn’t really green, it just has a protective layer of polythene on it. Then I took it off again and took it home.
Back home where the facilities are a little more advanced than kneeling on the grass at Kelpie I tidied up the marking out using a long batten to draw a nice arc at the front and adding 30mm fore, aft and outside edge.