I've various lengths of these, which I find very useful. I'm beginning to see wider uses for them, linking them together. Some lock jigs use the same basic system but with just very short lengths.
I'm trying to find a source of the joining plates. I've seen them in China, but I don't want a 20ft box full. I've sourced suitable screws and the T-Nuts aren't a problem, but finding suitable material of the right thickness, etc., to make some of the plates up is proving difficult.
I've an idea that one of the US woodworking suppliers offers them as a separate item but I can't find who. Does anyone happen to know? They are just the 'U' shaped plates.