Sheet metal processing is a convenient manufacturing process for manufacturing parts from flat metal parts. Sheet metal is available in a variety of materials and thicknesses for the manufacture of parts such as appliances, housings, brackets, panels and chassis.

For those new to sheet metal, the process looks daunting. Unlike many processes such as 3D printing and CNC machining, sheet metal processing is determined by fairly strict design practices. Metal sheets must be bent and cut in a specific manner and are only suitable for certain parts and products.

Therefore, it is important to learn some of the basic principles of sheet metal processing before starting a project. This guide provides five simple tips for improving sheet metal parts and turning ordinary designs into professional quality sheet metal products.

What is sheet metal manufacturing?

Sheet metal processing is a group of manufacturing processes that share common characteristics: they all use metal sheets - not blocks, powder or molten metal - as raw materials. Different machines form metal plates in different ways: some form holes or slits in the metal plate; others bend, emboss or rotate the metal to turn it into various shapes.

With sheet metal processing, engineers can use a variety of metals to make durable, low-cost parts. These components can be used in a variety of industries, from aerospace to pharmaceuticals to robotics.

The metal sheets used in the manufacturing process are typically between 0.006 and 0.25 inches (0.015 and 0.635 cm), depending on the end use of the given material and component.

Improve sheet metal parts

Sheet metal processing is unique in a variety of manufacturing processes because its materials are different from other materials. Therefore, it may be difficult to design sheet metal parts when designing parts for machining, molding, and other common manufacturing processes.

While the best way to ensure high quality sheet metal parts is to consult and use, it is also beneficial to follow certain design principles from the start. By observing the following five tips, designers can create sheet metal parts that are sturdy, easy to manufacture, and resistant to breakage.

hole

Since sheet metal manufacturing is often used to make outer casings, brackets, and the like, screws, bolts, or interlocking portions typically require holes and slots. The holes are typically formed by mounting the punch and die in the press, allowing a precise circular shape to be cut from the metal sheet. However, if the hole is not properly manufactured, the hole may be deformed or even cause the part itself to break.

There are some important rules to follow when punching holes in metal plates. Any hole in the wall or edge should be 1/8" (1/16" if the thickness of the metal plate is less than 1/30", and the spacing should be at least six times the thickness of the metal plate. In addition, all holes and slots The diameter should match or exceed the thickness of the metal sheet.

Hem

Metal sheets can have rough or sharp edges, so "flanging" these edges - folding them themselves - is a good way to make sheet metal parts safe and effective. The hem can also reinforce the sheet metal part or function, for example to accommodate the hinge pin. The hem can be open, closed or teardrop shaped.

When adding a flange to a sheet metal part, follow some guidelines to ensure optimum performance. For beginners, it is almost always better to avoid the closed hem - the material is completely folded over itself - unless absolutely necessary. Due to the extreme angle of the bend, the closed hem has the risk of damaging the material, so it is preferred that the opening and the teardrop hem are placed between the sides of the hem.

When making the opening flange, the diameter of the gap should match or exceed the thickness of the metal sheet. Return length - the distance the hem "returns to itself" - should be no less than four times the thickness of the sheet metal. The same guidelines apply to the teardrop hem, and the opening at the end of the return is not required to be no less than 1/4 of the thickness of the sheet metal.

elbow

Bending is one of the most important forming processes in sheet metal manufacturing. Using equipment such as brakes and machine presses, the machine shop can make metal sheets into new shapes - although some materials are more suitable for bending than others. Following certain rules regarding bending ensures accurate and uniform bending and reduces the likelihood of material damage.

One rule to follow is that when designing a sheet metal part with a bend, the internal bend radius should match or exceed the thickness of the sheet metal to avoid deformation. In addition, maintaining consistency in the direction of curvature and radius helps to reduce costs because the component does not have to be reoriented and the bending device can repeat the same process.

gap

Notches and tabs are features of sheet metal parts that can be used to add screws or fasteners or to insert multiple components together. The notch is a small indentation on the edge of the part, and the protrusion is a prominent feature. The tabs in one sheet metal part are typically joined into the recesses of the other part.

As with other sheet metal functions, there are certain rules to follow when creating the appropriate slots and labels. The notches should be about 1/8" apart from each other and at least as thick as the metal plate. The tabs should also be spaced apart from each other - the distance is equal to or greater than the thickness of the metal sheet. In addition, the length of the label should be equal to or less than five times its width. .

finishing

While sheet metal parts typically have relatively tack-free applications, they sometimes require one or more finishing processes to be performed before they are ready for use. Depending on the application and materials used, sheet metal parts can be finished by pearlizing, anodizing, electroplating, powder coating and various other processes for functional purposes or simply improving the appearance of the part.