Over the years I’ve made a few blanking dies for people with this
technique in mind. The simple beauty of using a pancake die is that
with one punch it creates two pieces of metal that share a common
sheared edge. Simply, it means that the positive and negative (or the
part and the scrap) will fit back together EXACTLY. The large spiral
design in the photo is a wonderful example of this ; I just recently
did it, and dug out a couple of other samples from my box of goodies,
to also be included.
The cityscape design was done with 3 dies; one that cut a circle
blank, and two that were the upper and lower building profiles. There
is a visible gap in the assembly, which I believe (too old for me to
remember ) was an accident, a mistake in pressing the parts together.
The spiral is done correctly, and it’s not like it’s a hard thing to
do, because with a little care, it’s impossible for the parts NOT to
get pressed together exactly. As the spiral shows, the fit is
absolutely airtight exact. I think some people can really have fun
designing things for this method.