Designing a Rock and Roll bed

I decided to make my Rock and Roll bed in the end as it was much cheaper and as I never intended the seats to be 'driving' seats I wasn't too worried about making super strong perfect steel joints and figured my novice welding skills would suffice. Plus this would cut down on overall weight as I could make it thinner and lighter and I can easily lift the whole thing in and out of the van on my own.
I designed it all on Google SketchUp and bought some 15mmx15mm box steel. about 6m in total.
It has two folds as you can see in the pictures. I wanted to be able to utilise the back area of the seats as well, so when the back door is open I can sit facing out as well.
My welding improved as I went along but it is still pretty 'rustic' so I won't show you any close ups.
I used a 'piano hinge' for the seat back and fabricated some special hinges for the back of the seats as it would have squashed the foam at the back otherwise.

I then pop-riveted some thin ply for the seats and backs and bought some good quality foam for the mattress.

I am pretty pleased with the results and it is almost more comfortable than my bed at home.

The whole thing needs some primer and hammerite on it and it will be complete.