For designers (and others) interested in making metal business cards that fold up and out into interesting shapes, I have some notes to pass along. I can’t help you design a card, but I can help you avoid some of the pitfalls. In no particular order, then, some tips:

Score your bend lines. To get a shape to pop up as desired, you need to be able to define where and how the metal bends. Not surprisingly, you do this by weakening the metal (scoring, essentially) at the place you want it to bend. Using the hand card as an example, the fingers are articulated because they bend where the knuckle design is etched; not below, not above, but right at the knuckle where the metal is weakest.

3 ways to score. The photochemical etching process, at least with 0.01″ sheet steel, etches at 2 depths: half-way, or all the way. So we have 3 basic ways to plan where the metal will bend: half-way, all the way, or not at all. Let’s take a closer look:

1. Make it skinny. The metal will bend where the metal is weakest, and it is weakest where it is narrowest. Pretty straightforward, this.
2. Etch a score. By etching a line all the way, or even most of the way, across the metal, you thin the metal at that point, forcing it to bend there and not elsewhere.
3. Perforate. A variation of #1, perforation is a series of small narrow points. But the basic rule is the same: less metal = more bend.
4. Mix and match. Try some combination of the 3… maybe only perforate to half-depth, or make it skinny and scored.

Bend + bend + bend = break. Understand that bending sheet steel also weakens it, and repeated bending along a score will eventually lead to a break. Unfortunately, I learned this the hard way. As neat as the Hand + Eye cards are, that thumb can really only be well bent a couple of times. Then you have a thumbless hand.

Remember your papercraft. While there are many things metal can do that paper cannot, like hold a bend, metal cannot do everything paper can: without tools, you can’t fold it, roll it, or tuck a flap under another flap (think origami). Nonetheless, the history of papercraft is rich with technique that can be applied to metal. Start looking there for ideas.

Get samples. The biggest piece of advice I have is to get samples of the sheet steel, cut it up, play with it, bend it, destroy it. You won’t really know how the metal will behave during bending until you test it out for yourself.

That’s about it. Have fun, stay safe. If any of this is helpful to your project, please share your results with the class.