There are enclosure manufacturing company that custom builds electronic enclosure for you. This means that the company can specify the cutout as they wish. Normally this include the functional cutouts specifically made for connectors, displays, switches and other necessary accessories. Despite of these, engineers often see the creative side on the cutout designs and this include company logos, branding and other product names. The creativity that goes around the ventilation cutouts are derived from the combination of form and function.
With this in mind, the sheet metal enclosures and its parts are being bent using a press brake or a folder. The sheet metal is usually cannot be formed into a perfect 90-degree edge. However if the corners have radius the company can do this.
There are varying degrees related to the curvature of the enclosure and this can be met by utilizing different tooling and bending parameters. As the engineer designer, this can be controlled by identifying the right bend radius – this is the radius inside the surface of the bend (which is outside the radius is just within the inside radius. Adding the metal thickness)
There are two major factors that can affect the bend radii:
Functional considerations: the company cannot have a very flat surface used for fasteners, components, or specific cutouts until such time that the company is clear of the bend radius.
Aesthetics: for example, the ‘retro’- style of some designs can bring in more and usually they have a larger radii for the curvier feel. This is to consider the right intentions in doing both aesthetics and functionality when it comes to designing so that the company can properly select the rightful bend radii to suit different needs.
In other words, the company should only be able to design enclosures with radii that can be actually built: this can be checked out if the radius capabilities chart from enclosure manufacturer companies can be matched with the equipment and tooling constraints of the company’s design. Once the company was not able to decide, I would like to suggest choosing something more realistic and the manufacturer can adjust the sizes for you before making the enclosure.
There are special consideration that should be given in order for the intersection of two bend lines (i.e. the corner) measured on the enclosure. To be specific, the extra material should be removed for the company to be able to prevent the bends from intersecting with each other. This case is called the corner relief (corner trim in CAD.) If the design engineer was not able to include the rightful corner reliefs, the manufacturer can add them for the company. There are available templates that can be used by any company who are in need of an enclosure.
In conclusion, the cutouts on the enclosure should be kept in minimum distance from the bend radii, this is because the cutout can be too close to a bend radius and it consists of risking the cutout by stretching or flaring. Actually, companies are always asked by their customers how far the cutout should be from the bend.