[above] I've been looking at options for modelling the slate roof on the goods depot at Farthing. For what it's worth, here's a quick overview of the options considered. Above is one way of doing it: Lengths of thin card strips scribed vertically, and overlaid. I think this can give good results - in 4mm at least.
[above] But thin card also has its drawbacks! I recently noticed that the roof on the parcels office at Farthing has buckled. Either the glue has simply let go, or it was caused by a repaint I did a while back. Using the same method but with plasticard might have been better, as convincingly demonstrated in this blog entry by 45584 (albeit in Gauge 1!).
[above] An alternative to scribing things yourself are these "ready-scribed" slate sheets from Slaters (ref no. 0427). The idea (I think!) is that you cut out each length and overlay them.
[above] I may have failed to grasp the concept here, but my experiments with the Slater's sheets suggest a significant overscale thickness of the slates (according to the Slaters catalogue, the plasticard thickness is 0.015'). Or have I misunderstood something? Until someone tells me differently, I've decided not to continue down this road.
[above] A third main option is of course the ready-to-fit embossed sheets, available in various guises. There seems to be two main types here: Those that are printed "flat", and those where the slates actually appear to "overlap". The flat-printed ones can sometimes work well: This roof on a (rather careworn) Coopercraft platelayer's hut gives a reasonable representation, I think.
[above] However, the Wills slate sheets seem to me the best of the ready-embossed solutions I've seen yet. The shingles actually give the impression of overlapping....
[above] ...and they have an ever so slight irregularity that can be further accentuated during painting and weathering, as on the right.
[above] But of course, nothing is perfect. One well-known issue with the Wills sheets is their limited size, which means several have to be joined for larger rooves...
[above] ....and another issue is their thickness. I don't think the individual shingles look overly thick, but at the edges it becomes more of a problem, as seen on this canopy on the goods depot.
Nevertheless, so far I think I'll go ahead with the Wills sheets as the preferred choice. There is also the option of cutting individual shingles of course, but I don't think I have the stomach for that right now...