Slotted Curves

The base of the venue - the pieces that hold the wooden fins in place - are proving tricky to fabricate. Working from the architects original drawings, which leave a large amount to the imagination, I drew out new shapes from those included in one of the plan views. The curves work out to be only 5mm x 5mm (high x wide) in 1:40 which, will make them incredibly delicate to work with. The wooden fins will sit in 2mm deep slots that will run all the way along the curves at regular intervals but at varying angles. The fins follow a basic wave shape, starting off at near perpendicular to the outer face and then shaping away from that angle and then back towards it again. The fins also have a staggered lean to them all the way round. The base of each fin lies square to the ground but the tops appear to be square to the parallel sides.
I've chosen to laser cut the curves out of 5mm acrylic, etching (in two passes) the slots and then cutting the curves out in one run.

 Attempt 1 (fail) After doing one etching pass, which took and hour and a half, I ran out of time on the laser. Ed etched locator points in the corners but when we tried to line it up a few days later (when the laser became free again) it didn't etch in to the same points and messed up the sheet of acrylic. I came back the following morning and did it all again with black acrylic. Below are the results. 1.8mm etched slots in a 5mm x 5mm curve. 

 The three etched curves

 Etching

The curves in their entirety

From this point I have sanded the curves smooth, as the sides were grooves from the etched lines. I started with a fine sand paper and then progressed to 320 and then 500 grit wet and dry. I will be spraying them a very dark grey - graphite or charcoal - to match the colour shown in the graphic illustrations from Jonathan Knox.