Pencarrow
Western Thunderer
Anywho, I've been wide awake since 3am so I might as well post some roof progress.
The width of the building now varies as the side wall and beam are displaced outwards. The gutter line on that side has also sunk. Dodgy builders! This will effect the position of the ridge line. But how much?
I cut a cocktail stick to the length of the slope at the gable end. This was to work out how much vertical sag to put in the ridge line and where the horizontal curve should go. A slightly iterative process offsetting the ridge line strip horizontally so that the cocktail stick hit the same vertical point on each side at intervals along the ridge line.
Once the horizontal curve was formed, and the glue set, the ridge line was trimmed vertically along those points. Triangular formers were then cut to suit each location but with a slight sag cut into the diagonal.
The smaller triangles were put in initially to hold the curve in place and make the base more rigid to aid measuring up the triangles.
Horizontal strips of 20thou were then added following the curved formers.
This is the side adjoining the second building so the gutterline is reasonably straight. Turning it around you can see how the top strip has been trimmed to the shape of the ridge line. Note also holes drilled in the base to let the solvent vapour escape.
Repeat with the horizontal strips on this side. Note that the strips fit within the gable ends flush with the top.
Strips of 30thou were then added across the roof at 90deg to the first layer. Note the these strips overlap the gable ends.
Why 2 layers and thin strips rather than just one large rectangle? This is to overcome issues I've had over the years with roofs coming unstuck and not following the curve of the formers. Very annoying when the roof pops and lifts - the plasticard doesn't like being curved or dished.
Working in strips allows you access to make sure each gets a good dose of solvent to the former. The thin strips also readily take up the curved profile and the two layers make for a rigid surface. It doesn't matter if they don't exactly join along their entire length as they will be covered in tiles.
The end result is quite satisfying to see the subtle curves and irregularities. Easy to see and feel but hard to pick up in a flat photo.
Looking the part and now lots of tidying to do on the stonework corners and joins.
The width of the building now varies as the side wall and beam are displaced outwards. The gutter line on that side has also sunk. Dodgy builders! This will effect the position of the ridge line. But how much?
I cut a cocktail stick to the length of the slope at the gable end. This was to work out how much vertical sag to put in the ridge line and where the horizontal curve should go. A slightly iterative process offsetting the ridge line strip horizontally so that the cocktail stick hit the same vertical point on each side at intervals along the ridge line.
Once the horizontal curve was formed, and the glue set, the ridge line was trimmed vertically along those points. Triangular formers were then cut to suit each location but with a slight sag cut into the diagonal.
The smaller triangles were put in initially to hold the curve in place and make the base more rigid to aid measuring up the triangles.
Horizontal strips of 20thou were then added following the curved formers.
This is the side adjoining the second building so the gutterline is reasonably straight. Turning it around you can see how the top strip has been trimmed to the shape of the ridge line. Note also holes drilled in the base to let the solvent vapour escape.
Repeat with the horizontal strips on this side. Note that the strips fit within the gable ends flush with the top.
Strips of 30thou were then added across the roof at 90deg to the first layer. Note the these strips overlap the gable ends.
Why 2 layers and thin strips rather than just one large rectangle? This is to overcome issues I've had over the years with roofs coming unstuck and not following the curve of the formers. Very annoying when the roof pops and lifts - the plasticard doesn't like being curved or dished.
Working in strips allows you access to make sure each gets a good dose of solvent to the former. The thin strips also readily take up the curved profile and the two layers make for a rigid surface. It doesn't matter if they don't exactly join along their entire length as they will be covered in tiles.
The end result is quite satisfying to see the subtle curves and irregularities. Easy to see and feel but hard to pick up in a flat photo.
Looking the part and now lots of tidying to do on the stonework corners and joins.
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