[eddie_ce]

vidjoman - I thought about the paper, transparent plastic, however I have found in the past that I either get annoying air bubbles in the plastic or the edges start to curl up and become loose.

Another advantage is that my cut outs didn't need to be precise, the underlying material being 1,5mm steel which is not that easy for me to work with. The CNC machined aluminium panels provide the necessary precision.

sven - I'll try to get a better image, possibly as a pdf.