Photochemical machining (PCM) is a metal fabrication technique that serves as an economical alternative to other manufacturing processes, such as CNC machining, punching, laser and waterjet cutting, and electrical discharge machining (EDM). When used to create precision thin metal parts, it offers several advantages, including higher customizability, lower tooling costs, and faster turnaround.
At E-FAB, we use photochemical machining to produce a wide range of precision thin metal components for use across a diverse set of industries. The process allows us to create parts with complex or intricate geometries to tight tolerances at competitive prices.
Photochemical Machining Process
Photochemical machining is an umbrella term referring to several different processes, including photochemical machining, chemical blanking, microchemical milling, and photo etching. Industry professionals use these processes to take a part design—typically developed using AutoCAD software—and fabricate the desired part from sheet metal.
Stages of the Photochemical Machining Process
A PCM operation typically involves the following stages:
- Creating the phototool—a component containing a negative image of the desired part used to block UV light from reaching specific sections of the workpiece
- Cutting, cleaning, and applying photoresist—a light-sensitive compound—to the workpiece
- Placing the phototool on the workpiece
- Exposing the workpiece to UV light, which hardens the exposed photoresist
- Washing off the unhardened photoresist
- Etching the unprotected areas using specialized etching equipment and etchant
- Removing the hardened photoresist to reveal the finished part
Advantages of Photochemical Machining
When used for the manufacture of precision small and thin metal parts, photochemical machining offers a number of advantages, including:
- Lower costs. As photochemical machining operations employ chemical etchants and digitally rendered designs to produce a finished part, the cost of tooling is minimal compared to mechanical machining operations. Additionally, the process accommodates part designs with greater complexity or requiring tighter tolerances without significantly raising the cost of production.
- Faster turnaround. The digital nature of PCM part designs facilitates quicker production of prototypes and production-quality pieces. Even if a customer requests changes to the part design, design engineers can easily modify it through computer software without having to invest in new tooling.
- Broader production versatility. The PCM process is highly versatile, accommodating parts made from a variety of metals in a wide range of shapes and sizes. Additionally, the process is suitable for prototype to full-scale production runs.
- Higher quality surface finishes. PCM produces parts with minimal surface burring, reducing the need for additional finishing operations.
Photochemical Machining Capabilities at E-FAB
At E-FAB, we use photochemical machining to process a variety of metal and composite materials into parts for a wide range of industries. The following table outlines some of our capabilities: