Getting the metal back plates made has turned out to be more complicated than expected. Martin’s been great though, doing a lot of running around and liaising with the suppliers.
It seems the main issue was the need to create an L-shape piece with the base side flat but the rear trem cavity plate curved with the same radius as the body so as to fit flush with the wood surface. This meant that simply folding a single sheet of metal wasn’t going to work – the fold itself would have to be curved, which I imagine is impossible or at least very difficult. The plate will instead have to be formed from two pieces welded together, with the weld then ground smooth. Hopefully this will look fine, but we won’t really know until they’re made.
Another issue is the size of the production run – the suppliers were reluctant to produce only a small number of plates, as it’s really only cost-effective when talking about hundreds of units. Martin managed to persuade them to go for a run of ten, which is more than we need and makes the unit cost higher than ideal, but seems like a fair compromise. At least we’ll have enough to see us through the first full SB-1 production run (I’m envisaging a limited-edition batch of five to start with).
Anyway, they’re cracking on now, so hopefully they’ll be ready soon so we can finish assembling the production prototype.