The Photochemical Etching Process

Metal frames always tend to get their attention with their attractive appeal. A handmade metal frame may be more attractive for special efforts in its manufacture. In fact, these handmade metal frames can also be great gift options. Here’s a step-by-step procedure for making a metal photo frame using a couple of inexpensive items. Photochemical engraving, one of the world’s most kept secrets, produces identical high-precision parts for both large and small operations. Photochemical engraving used in various industries including: automotive, communications, electronics and precision engineering. The process can produce different designs, to large batches of identical parts.

The photo-etching process involves applying a photosensitive polymer to a raw metal sheet. Using computer-designed photographic tools; the metal is exposed to ultraviolet light to leave a pattern of design. This pattern is then developed and engraved from the metal sheet. The shape of the resulting component is cleaned and sent to a finishing workshop for training, surface treatment and inspection.

Photographic tools are so profitable to produce relative to traditional tooling methods that design revisions can be implemented at a fraction of the cost. Once a photographic etching material has been selected, it is essential that all contaminants are thoroughly cleaned. This guarantees good surface conditions for engraving.

The photographic engraving process can be achieved through several different lamination methods, including rolling, wet or drying. This wide range of approaches allows the manufacture of metal components with thicknesses ranging from 10 microns to two millimeters.

During the lamination process, it is important that the contact between the photosensitive and the metal layers is uninterrupted. A clean, controlled environment will ensure the best and most efficient result.

The sheet metal is interlaced between the photographic tools before exposure to an explosion of ultraviolet light. UV light hardens the selected areas of the laminate on an acid-resistant surface. The sheet is then developed and any unexposed laminate is washed transparent.

Then an acid solution sprayed onto the sheet, dissolving the exposed areas of metal and revealing the design of the product. If the metal is exposed to the front photographic tool only, the acid will be engraved on one side. If the front and rear photographic tools contain hobby areas, the metal will be completely removed, leaving smooth, cut-free edges without affecting the material properties. The remaining resistance is removed to reveal the finished product.

The process offers a natural solution to many design challenges. A wide range of technical finishes and veneers improve conductivity, offer insulation properties and improve corrosion resistance.

Components can also be formed into complex, three-dimensional designs. When recording a straight score mark, folding edges can be formed for a variety of applications, including RFI shielding for electronic systems.

Because photographic tools are highly wear-resistant during operation, the first component is identical to the last, regardless of how many batches are produced.