Helicopters are complex pieces of aviation machinery with a wide range of components that work seamlessly together. One basic premise that all pilots must remember for every flight is this: if the rotors don’t work properly, the elaborate and costly sky chariot goes nowhere.

One of the critical components of rotor blades is abrasion strips, which protect materials on rotors from impact and erosion. Water, dirt, volcanic ash, and sand can all contribute to erosion, which reduces energy efficiency and performance. Helicopters used in military operations are particularly susceptible to sand and abrasion strips—also called leading edge guards—help keep helicopters sky-bound.

The process by which abrasion strips are manufactured is a rarely used process called electroforming. Similar to 3D printing, electroforming joins materials layer by layer. The difference, however, is that electroforming builds up metal parts atom by atom, one tiny piece at a time. Components manufactured through electroforming can be quite large—up to 6,000 pounds and 17 feet long.

Parts for aerospace, defense, and medical industries are made with the electroforming process. Chemical, mechanical, and industrial engineering principles are all interwoven into component production, and the process allows for near-identical reproduction.

Electroforming is a form of additive manufacturing but is more precise than a current manufacturing favorite, 3D printing. “It’s much more widely accepted,” says Luigi Cazzaniga, Director of Engineering for Alpha Metalcraft Group (AMG), one of the world’s leading manufacturers of electroformed components and formerly known as AlphaCoin. “One, because it has been around for more than 100 years. And two, because the process involves depositing material at the molecular level. 3D printing doesn’t have the precision or control over mechanical properties that electroforming can provide.”

Built In a Bath

In electroforming, parts are built using a mandrel, or the inverse model for the component. The electrolytic solution—which is frequently referred to as a bath—includes anode and cathode electrodes. An electric DC current passes through the electrodes, which causes metallic ions in the solution to migrate and attach to the mandrel’s surface. Layers build up around the mandrel.