Earlier this year I posted about dies that were etched and used as two-step dies to emboss and cut metal parts. There turns out to be a potential flaw in that approach, at least for some designs, and so I’ve changed the approach to one where this potential is eliminated.
The area for possible trouble is using the cutting die itself as an impression plate; specifically, the connection area between design and hinge is put under tremendous stress. I have always spot annealed that area after hardening because it needs to flex a little (the edge of the metal piece being cut creates a fulcrum point that forces the die to bend there during cutting), and so it can’t be as hard (brittle) as the rest of the die. The potential problem arises from the fact that the pressures involved in forming metal into a die like this are enough to permanently deform steel that’s too soft. The spot annealing is to remove some hardness/brittleness there where it needs to flex.
Recent experience with thin hardened steel impression plates has shown that they can crack and break if they’re too hard or become dished if they are too soft. Both situations are also true of the etched RT die being used as an impression plate, and I decided that the risks were not worth it, so a new approach had to be found. Most of the etched pancakes can still work well with a slight tweak to the process, which is to use the die to emboss metal BEFORE it’s cut in the die, as opposed to AFTER a piece is cut, which was the original procedure. But this didn’t completely, universally eliminate potential damage to all designs on all such dies.
The original version above I now call V1.0. An interim version consisting of an etched pancake and separate impression plate is called V2.0. Some of these were made because I already had the etched pancakes. V2.0 is a very good solution, but etching the die and a plate adds cost, so I wanted a different, easier solution. Enter V3.0, the current default version as of August 2023. V3.0 consists of a plain cutting die with an etched impression plate. All 3 versions have a video (youtube link) because all 3 are in existence, but I’m only making V3.0 now , except by request.
One obvious unknown when I was formulating V3.0 was whether or not the embossing would get smashed in the press after being cut. Pieces with more depth to their embossing or forming do need a protective base attached to the cutting die, for the piece to fall into so that the die can’t close down on top of the part. Fortunately, it turns out that the impressions formed by these etched plates are shallow enough and gain enough work-hardening strength from pressing , that they are not at much risk for damage. All it takes is a thin layer of cushioning to prevent any significant injury. I have used thin, dense cardboard , thin craft foam, and thin (1/16" maximum) urethane, laid between the piece in the die and the press surface.
I lean away from urethane because it allows the whole die to flex. The other materials allow less flexion.
With such high pressures concentrated onto small areas on thin plates like these, there is still potential for either cracking or deformation, depending on the hardness of the steel. A more generous comfort zone would be facilitated by using , say, 1/2" thick plates, but this isn’t practical for me at this stage (keeping costs down). My reasoning being, if an impression plate breaks, that’s bad, but not nearly as bad as a pancake die breaking. If a plate dishes a little, smash it in the press to flatten it out and keep on truckin’.
The mushroom, butterfly, and turtle examples below are typical V3.0 . The tiger samples show the results of using either a single die to cut left and right parts, or using a mirrored pair of cutting dies for an asymmetrical design. With a single die, the design will either face in or out during cutting. Facing out, it benefits from the cushioning layer mentioned above. Facing in, there’s no way to cushion it directly (no loading of such materials into the die during cutting is allowed !). Fortunately, again, the design area has gained enough strength to survive without damage. I do use the cushion under the die anyway when the design is facing in, because it does keep the part from being squeezed against two hard surfaces.
That’s the short and sweet of it 
Feel free to contact me - Dar Shelton on Facebook. sheltech at yahoo dot com email . #theactualdarshelton on IG
