Metal Springs/Contacts

Metal springs/contacts produced using etching technology are metal components that are manufactured by selectively removing metal from a thin sheet or strip of material to create a specific spring or contact design. This process of chemical or mechanical etching allows for the creation of precise and intricate patterns with tight tolerances.

The etching process begins with the creation of a detailed CAD (computer-aided design) drawing of the desired spring or contact pattern. A thin sheet of metal, such as stainless steel or copper, is then coated with a resist material and exposed to a UV light source through the CAD drawing. The areas of the resist that are exposed to the light become hardened, while the areas covered by the CAD drawing remain soft and can be washed away with a developer solution.

Once the resist has been removed, the metal sheet is placed in an etching solution that selectively removes the unprotected metal, leaving behind the desired spring or contact pattern with high precision and tight tolerances. The etching process can also be used to create complex shapes, intricate patterns, and fine details that may be difficult or impossible to achieve through other manufacturing processes.

The resulting metal springs/contacts are highly precise and can be used in a wide range of applications, including electrical contacts, connectors, and switches. They offer reliable and consistent performance due to the uniformity and precision of the etching process. The customizable nature of the etching process also allows for a wide range of metals, thicknesses, and finishes to be used, making metal springs/contacts produced using etching technology a versatile and reliable material for many different applications.

Chemical etching process: 10 frequently asked questions

Want to ask a question about chemical etching or share a component drawing for technical review?


Q1. What is the chemical etching process?
The chemical etching process is a sheet metal machining process that is used to manufacture complex components with high levels of accuracy.Comprising nine steps, it works by printing the component design onto a photoresist mask which is laminated onto the metal.
The areas of photoresist which have not been printed are developed, exposing the metal, which is subsequently etched away.
Q2. What metals can be chemically etched?
Almost any metal and metal alloy can undergo chemical etching. This includes steel and stainless steels, nickel, copper, aluminium.
What makes photochemical etching so effective is that it works well on hard-to-machine metals, including highly corrosive-resistant metals such as titanium and its alloys.
Q3. What chemical is used in etching?
Most metals are etched using ferric chloride, a safe to use, recyclable etchant. Ferric chloride can be regenerated and reused.
Other proprietary etchants such as nitric acid, are used for specialist metals and alloys.
Q4. What sheet sizes and thicknesses can be etched?
Sheet metals between 0.010mm and 1.5 mm thick can be etched. The thicker the sheet the longer it takes to etch, meaning metals above 1.5mm are uneconomical to process.
Q5. How accurate is chemical etching?
Excellent accuracy can be achieved with photochemical etching. Standard minimum etching tolerances are ±10% of the metal thickness being etched, to a minimum of ±0.025 mm.
With development, greater accuracy can be achieved so it is encouraged that customers partner with TONGJIN Etching early in the design phase so an appropriate etching method can be developed.
Q6. What are the benefits of chemical etching?
Chemical etching is highly advantageous and offers many benefits. This process does not use mechanical force, unlike stamping which subjects sheet metals to extreme pressures. Nor does it put thermal stress on the cutting edge, unlike laser cutting.
Alongside this, chemically etched parts remain flat, burr- and stress-free, leaving the material properties unaffected.
Chemical etching can also produce very accurate engraved features at the same time the material is being profiled, such as fluidic channels, logos or part numbers. These features come at no additional cost.
Q7: What level of detail can chemical etching achieve?
The minimum standard etched opening achievable is 0.1 mm, but with development, etching can achieve even finer features.
Q8. How much does chemical etching cost?
Chemical etching uses digital tooling which is inexpensive, very easy to adapt and does not wear out, unlike presswork tooling.
Material thickness and component size are key cost drivers as you pay by the sheet, not by the part – the more parts per sheet, the lower the unit price. Thicker sheets take longer to etch and this is reflected in the cost of the component.
Q9. What are the maximum quantities chemical etching can produce?
There is no maximum quantity that chemical etching can produce.  Low-cost digital tooling ensures prototype quantities can be supplied quickly and economically.
As one of the largest sheet metal etching companies in the world, TONGJIN Etching supplies its customers with component quantities measured in the millions.
Q10. How long does chemical etching take?     
Chemical etching lead times are measured in days, not weeks or months, unlike traditional metal machining technologies.
Subject to quantities required and capacity, standard components which require no additional post-processing can be supplied in less than two working weeks. Urgent demands can be supplied even quicker.

Recently Viewed Products

Ready to discuss your component design?

Share your details for technical review & pricing or contact us.
Contact us now