I’ve been considering the technical challenges of fabricating the penguin weathervane. Although it was clear that the best approach would be to laser-cut the design from brass or copper sheet, I needed to work out the best way of setting the coloured glass panels into the structure.
After discussing the issue, I felt the best approach would be to cut a 4mm central brass sheet rebated by 4mm around the glass panels, which would themselves be oversized by approximately 3mm. On each side of the brass sheet, additional fish and penguin laser-cut 1mm copper panels will be used to retain the glass. The three layers will be held together with brass leather screws and the glass panels silicone bonded.
The advantage of using brass overlaid with copper is that copper weathers darker than brass, so the bodies of the penguin and fish will be subtly distinguishable from the water lines and bubbles.
In order to prepare the design for laser cutting, I needed to clean it up and convert it to a vector image. So in preparation I converted the design to solid colour in Photoshop by increasing the threshold to maximum. I then mapped out the fish and penguin panels in layers and replaced the drawn water bubbles and eyes with circular shapes, the centres of which were cut out using proportionally reduced circles. Finally I re-coloured the water and bubbles to a dark grey to represent the colour difference between the weathered copper and brass.
Once the overall size has been agreed, I can work out the 4mm glass rebates in the brass panel and send the design off to be cut.