Chemical Etching Metal
Chemical etching, another industry name for photo etching and photochemical etching, is a cost-effective manufacturing process for a variety of industrial thin metal parts. The photo etching process is ideal for the precision machining of parts with simple to complex designs.
The chemical etching process does not use points of contact with the metal like mechanical tooling as in the stamping process, or a laser beam and electrical discharge in the laser cutting, and wire EDM processes. The use of an acid chemical etchant simultaneously dissolves away the unwanted metal of the desired part. As a result, parts are burr and stress-free while metal properties remain intact.
Metal etching is the smart option for parts with complexity such as intricate designs with numerous holes or slots. The etching process saves time and money as those features are etched simultaneously and there is no extra charge or set up time per feature. Large volume production with complex parts are more cost-effective and provide faster lead times than other manufacturing processes.
Another chemical etching capability is half-etching. This feature is beneficial for parts that require forming. The half-etched lines, otherwise known as score lines, will make the part easy to form manually, thus eliminating stress in very thin parts while saving the money and time it would take to use a forming tool. Half-etching is not limited to one side of the metal, nor does it increase etching costs. Logos and numbers can also be etched at the same low cost.
Prototype development is essential in every industry and ongoing for product improvements and new design testing. Since photo etching tooling is digital, revisions are done quickly with minimal cost. As a result, prototype parts get out the door faster to keep your projects on schedule.
Chemical Etching Metal - Technical Guidelines
The chemical etching technical data below highlights our chemical etching capabilities and lowest tolerances achievable based on many variables such as metal thickness, metal type, sheet size, production volumes and part design dimensions.
Our goal is to design a photo tool with as many parts per sheet of metal as possible. As a general rule of thumb, thicker material and lower tolerances will require a smaller sheet yielding fewer pieces. On the contrary, thinner metal with an extended range of tolerances will increase sheet size and part pieces. Photochemical etching techniques are designed to achieve the lowest possible tolerance and the highest number of parts per sheet in order to save you time and money.
Parts can be tabbed in the sheet for better transport, to help maintain dimensional tolerances or if secondary finishes are required, at no extra cost. Or, if tabbing is not an option for functional or dimensional purposes, then the parts are classified as "dropouts" and special packaging is included. Please refer to "What is the Photo Etching Process?" to learn more about photo etching techniques and the special types of tabs that are available.
|Table 1: Etched Dimension Tolerances (results may vary based on sheet size, metal thickness, and production volumes)|
|Thickness (T) in inches|
|Table 2: Holes or Slots|
|Metal Thickness (T)||Diameter or Width|
|.001" -0.005"||At least Metal Thickness, Minimum .003" width and .005”diameter|
|.005" or Over||Minimum of 1.1 times|
|Table 3: Web or Finger|
|Metal Thickness (T)||Space Between Holes (W)|
|Less than 0.005"||At least Metal Thickness, Minimum .003"|
|Over .005"||Minimum of 1.0 times|
|Table 4: Center to Center Tolerances|
|C/C Dimensions (inches)||Tolerance Attainable|
|1.0" or Less||±.0005"|
|1.0" - 3.0"||±.0010"|
|3.0" - 6.0"||±.0020"|
|6.0" - 10.0"||±.0030"|
|Table 5: Half Etch Based on Material Thickness|
|25% - 75%||100% +||25%|