Today, in lovely sunshine, we started to get the final set of special LVL rafters created. We first went outside to install the three corner legs for MN, NO and OP corners. We chopped a small bit off the ends to make them fit nice and tight into their corners and then measured the distance of the bottom flange from the steel brackets to the face of the leg, down at the correct point. The numbers came out pretty close to the drawing as follows: NM was 5420 mm, NO was 4350 mm and OP was 4320 mm.
After an early lunch, with our freshly printed drawings of the NO and OP rafters, we started preparing all the material bits and pieces. The webbing plywood was sliced down to the correct width of 436mm (we had already made eight of them but at a wider size of 455mm), then sliced angled ends (32.7 degrees) on all of them in pairs. The LVL timber was next to get the treatment of being chopped with this 32.7 degree angles and then the bird’s mouth marked and cut away too. Finally, a heap of internal noggings (both straight and angled ones) were made. The final job of the day was to cut away clearance gaps within the webbing, at the wall end so when the rafters are lifted into place and slid into position, the wall’s top-plate can wiggle into the rafter and settle into the bird’s mouth properly without jamming up.
