I began plotting all the form blocks while waiting for my sheet to arrive. The first issue was the co-ordinates to plot the curves of the ribs. Distances are labelled in millimetres, with points of a millimetre, i.e. 20.7mm, 34.8mm and so on.
Wondering how on earth I could see, let alone measure mark and cut such distances, I asked Zenith. A quick reply from Nick advised me such measurements were for those who plotted them using a CAD program and that by checking the Construction Standards, I would see the tolerances were 0.5mm for the X and Y co-ordinates. Even half a millimetre is a ridiculously small tolerance, however I’ve done my best to get them as close as I can.
In the photos you can see I plotted all the co-ordinates then nailed a half-inch brad at each one. I then used a piece of cable conduit to bend around the nails to get the curve and drew the line. To hold the conduit in place I just cramped a block at each end.
I used 18mm MDF and cut them with a jigsaw. Got plenty of advice that this is a slow method, but being a carpenter I was confident I could get through quick enough.
I bought a 350mm disc sander and trimmed them all down to size with that.
