VW camper bed. All MDF, made to fit a standard 3ft mattress, paint: sprayed in original VW colours. Wheels,lights and badges are photos of original parts printed on to vinyl. Bed was a present for my daughters 16th birthday earlier this year.
Roof is a flat 18mm with a grove ran down the long edges. I cut 12 curves out of 18mm MDF and spaced them out equally along the sheet, then I left a sheet of 6mm MDF laying on it for a week it followed the curve on its own. Then cut it to width glued and nailed it to the studs