Photochemical Machining VS Chemical Etching: Two Processes, One Goal
Manufacturing technology has come a long way, and today there are several methods to produce high-quality parts with high accuracy. Among these methods are photochemical machining (PCM) and chemical etching (CE).
Both PCM and CE involve similar steps that include applying a mask or resist material to a sheet of metal, selectively removing material, and using chemicals to create a specific pattern. However, there are subtle differences between the two processes that can make them suitable for different applications.
So, let's dive in and compare PCM vs CE in terms of performance, quality, and cost.
Performance
In terms of speed and accuracy, PCM is the clear winner. This process uses a photoresist material that makes it possible to achieve high precision with minimal distortion in complex parts. Moreover, PCM can work with a wide range of metals, including copper, brass, stainless steel, and aluminum, and can produce parts with a thickness range of 0.001 to 0.125 inches. PCM can also produce micro-sized parts with tight tolerances up to ±0.0005 inches.
In comparison, CE is relatively slower and suitable for parts with simple geometries. CE can produce parts with a thickness range of 0.001 to 0.060 inches but may have a harder time maintaining tight tolerances. CE can work with similar metals as PCM but may have restrictions due to size and geometry.
Quality
Both PCM and CE produce high-quality parts, but the resolution and edge definition of PCM are superior. PCM can achieve an edge definition of ±0.0005 inches or better, and it can produce smooth surfaces with minimal material distortion. CE, on the other hand, may produce a rougher surface finish and may have limited resolution due to material displacement.
Cost
When it comes to cost, CE is generally more cost-effective for larger production runs due to lower setup costs. However, PCM is more cost-effective for shorter production runs, prototypes, or parts with complex geometries. PCM tooling costs are typically lower, and there are fewer setup costs to consider. Additionally, the photoresist used in PCM is less expensive than the resists used in CE.
In conclusion, both processes have their strengths and weaknesses, and the right process depends on the application. If you're after high-quality, accurate, highly-detailed parts, or smaller production runs, PCM might be a better option. On the other hand, if you have larger production runs, simpler parts, and the cost is a primary concern, you may want to consider CE.
References:
- "Chemical Etching vs. Photochemical Machining." Tech-Etch. Accessed June 1, 2021. https://tech-etch.com/chemical-etching-vs-photochemical-machining/.