There are countless numbers of perforating patterns possible with many types of hole, including round, square, hexagonal, rectangular, triangular and oblong. The most common patterns used in conventional perforated sheet metal are straight line and staggered patterns. In a straight line pattern, the hole arrangement can be determined by two parameters: Vertical and horizontal direction. To create a square pattern, both directions should have equal distances. If the distance in the vertical direction is not the same as in the horizontal direction, the perforated pattern will be called a rectangular pattern. Unfortunately, compared to a staggered pattern, this straight line pattern is not as strong as the staggered pattern due to the nature of the layout.

Besides all those uniform and conventional perforated patterns a new perforated pattern based on an image has also become available widely. This opens a new and exciting market opportunity for any perforated sheet metal project which can benefit both the supplier and the customer. Basically, the perforated pattern is generated by capturing the image’s colour by using a specific calculation / algorithm, and then all information is translated in a sophisticated way to create a pleasant perforated pattern design which reflects the original image in some way.

There are several considerations when designing a perforated metal pattern based on an image. These considerations are recommended to make the perforated pattern design reflect the original image as closely as possible and to reflect the pattern that the designer wants to have.

More hole types is better
More holes variation is likely to give a better result. In most cases, this is simply because the more holes that are used, the greater is the information that will be captured during the conversion process to generate the perforated pattern.

The proportions of Image and Perforated Sheet
A good perforated pattern design should have a size in proportion to the original image. If the original image size and the designed perforated sheet are not in proportion, the designer will be forced to stretch the perforated pattern. In some cases this could be done on purpose, but in general this should be avoided if you wish to create a natural looking perforated pattern design that reflects the original source.

Original Image Composition
Although virtually any image can be converted into a perforated pattern design, the color composition of the image plays an important role in getting the best results. In most cases, an image that has strong contrast and vivid colour separation seems to capture better in perforated pattern conversion. For example, a cartoon image or an Andy Warhol style painting are best suited to perforation conversion. The most difficult kind is an image photo that has smooth colour transition, light contrast or too-bright colour.

Viewing Distance to get an optimal representation of the perforated pattern
To design a better perforated pattern and to make the pattern reflect the original image optimally, a designer should consider the viewing distance between the perforated sheet project and the people who will see it. The viewing distance has a relation to the average hole size and the centre-to-centre distance between holes as well as the open area. Thus, if a perforated pattern is supposed to be seen at a distance of about 10 meters (eg: a car park building fascia), at this optimal viewing distance they will automatically recognise the image that appears on the perforated sheet. However when people see it at around 3 or 4 meters distance, they will just see the perforated pattern as a scattered, meaningless, hole pattern on the sheet.. On the other hand, if people see it from 20 or 25 meters away, they will see it as a dot image or a plain picture without automatically knowing that it is an art work created from a perforated pattern. The pictures below illustrate what people see when the perforated pattern design is too close or too far away.

Light arrangement to give better result
To make the image-based perforated pattern outstanding, we should consider the use of back light to give a better representation of the original image. Lighting sourced either from natural light (eg. sunlight) or artificial light ( eg. a spotlight) plays an important role in creating a better composition to improve the visual effect of the perforated pattern. Placing a bright light behind the perforated sheet will create a perforated shadow which can be even more sophisticated for the perforated pattern.

Creating a 3D perforated pattern project before manufacturing
It is a recommended, based on my last perforated project, that all perforated pattern designs are visualized into 3D design by using a third party 3D CAD software before they are manufactured. By doing this, the designer and the project owner can deliberately check to see whether all the design considerations, including material colour, texture, light arrangement, and perforated pattern design, are already suitable to their specifications. All in all, product alterations in the design stage are much cheaper than after manufacturing the real product.

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