The Ties That Bind Circuits

For the beginner just getting started with electronics, soldering seems like an impossible skill to learn. But as time goes by and circuit designs get more complex, it will become increasingly clear that breadboards aren’t going to cut it any longer. At this stage it is no longer an option — learn to solder or find a different hobby. The first soldering joints of those who continue on are nothing to be proud of, but with practice the connections get better and cleaner.

With enough time and practice, anyone can solder a surface-mount chip with one arm tied behind their back. But just because you know how to solder doesn’t mean that you want to solder. Highly skilled or not, it is just a chore. A group of engineers at Northeastern University has apparently had enough soldering, so they developed a system called ProForm that enables solder-free circuit assembly. Their approach involves applying pressure-formed thermoplastics to circuit boards, with surface components carefully aligned, to hold them tightly in place and make the electrical connections.

ProForm is based on thermoforming, a manufacturing technique used to shape plastic sheets. In this process, a thin thermoplastic is heated until soft, then pressed over a mold, cooled, and trimmed to fit. The researchers adapted this technique to electronics. Instead of shaping packaging, the plastic sheet is formed over a circuit board already populated with components. With the help of anisotropic conductive film (better known as z-tape), the components are kept aligned and in contact with their pads. When the plastic layer hardens, the parts are locked securely in place.

Soldering creates a permanent connection, which is great for durability but terrible for reusability. Desoldering parts is time-consuming, risks damaging both components and boards, and rarely works well at scale. ProForm, by contrast, creates a reversible bond. If a chip fails or a resistor needs replacing, the plastic can be cut away, the component swapped, and the circuit re-formed with another sheet of plastic. This makes it ideal for prototyping, where designs change quickly and parts are often reused.

Performance tests show that ProForm circuits hold up well. Electrical resistance stays low and stable, signal integrity is maintained at high frequencies, and the system can even handle motor-driving currents without degradation. This means that ProForm isn’t just a novelty; it’s a viable technology for real-world applications.

Of course, there are trade-offs. While ProForm works well for many prototyping scenarios, solder still reigns supreme in mass production. Nothing beats the mechanical strength, conductivity, and thermal tolerance of a soldered joint when devices are expected to run for years under stress. ProForm is also limited by the properties of the plastic layer. Very high currents or extreme temperatures may eventually cause problems. The process also requires access to a thermoforming setup, which — though possible with DIY equipment — is still an extra step compared to heating up a soldering iron.

So while soldering remains a rite of passage in electronics, its monopoly on circuit assembly is no longer absolute. For the hobbyist and prototyper in particular, ProForm offers a simpler way to assemble circuits.