Subject: RE: [CR] was: Re: Bilaminated Frame Construction, now: shapingmachine
I don't think it likely that a shaper would have been used to produce sheetmetal "lug" blanks.
A tracing nibbler, however, would have been just the ticket.
Using a nibbler to make "lug" blanks, you would first make a pattern guide which is attached to a sheetmetal blank. The pattern is smaller than the finished part and is moved against a guide pin while the blank is nibbled away to produce an identical (but larger) version of the pattern. One of the manufacturers where I once worked had a Heck nibbler which was used to quickly produce sheet metal brackets and other small parts.
BTW, in one of my visits to the Dawes factory I was shown how they used a cylindrical nibbler to miter the ends of the tubes, to basically nibble the fishmouths which they then touched up with a file. Very fast!