The roof trusses are up and painted and the roofing metal arrives tomorrow. At $15 a square metre it comes at a hefty price - and that's without the cutting!
The suppliers only cut each sheets at right angle to the height of the triangle. I have to make the twenty-or-so diagonal cuts along the side of the sheets to fit them into the triangular roof sections. It's done with a "nibbler" and it's tedious work. The "nibbled-off" off-cuts are then reversed to become the next triangle.
In this way I only have to cut the sheeting for two triangles. Their off-cuts become the ready-made sheeting for the other two triangles. That's the theory! ☺
Taking exact measurements is important! I could do it standing on the roof and risk falling off. Or I could do it on terra firma and risk no more than falling back on some basic trigonometry. Rather than being a Nibbler on the Roof, I chose the latter.
With each of the four sides of the roof being an isosceles triangle, it's easy to rig up a "cookie cutter" with two equal sides and two equal angles, each of which has to be 45° since the angle of the apex is 90°. Lay it over the assembled metal sheets and nibble away.
Let's see how the "cookie cutter" crumbles!
