Cut by machine process. Folded and finished by hand.
(As it happens, this particular example was cut by hand, just because I didn't have a machined one when I did the photos. If you buy this design, it will be cut by machine, hence rather more neat and accurate!)
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This is another very early design that has evolved through many stages.
It features a 'linkage' in the centre, where the 'anchor' shape from the lower half is fed through the loop on the upper half. This is rather fiddly to achieve!
This is the only design that features a linkage of this kind. It's not an idea I felt needed to be repeated.
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