Costo
5
Thanks guys 
Well, I don’t have measurements for this, because I never drew any plans, always working straight on the material (acrylic or wood).
They’re obviously based around the standard Elektron box size : 17.5 x 4.5cm, and I used an angle of 18.5° between them (but could have been 20° or 15°, that was totally arbitrary)
In paper, cut 2 or 3 rectangles with those dimensions, play around with them.
When you’re happy with the layout, trace it on the wood board with a pencil…
Toy with it, visualize it in your mind.
When you’re “sure” you like it, cut away…
That way, you’re sure to have your own design based on your own feeling.
And if you’ve got the tools (or have access to them), it’s very cheap, the biggest investment is time, so if you don’t like it over time, you can always start over.
Cheers !