If you want your custom sheet metal services for your project to go off without a hitch, it’s important to be clear on the sheet metal that your project requires and how to achieve it in the production process. That way, you can use an easy-to-clean material like aluminum and get the results you want from your manufacturing company’s production team.
Basic Sheet Metal Forming Process
The process begins with a sheet metal blank cut from bulk material. The edges are then deburred, or smoothed and straightened, to prepare for any subsequent forming processes. The sheet metal is then fed into a shearing operation that can create multiple blanks from one piece of sheet metal. Shearing can produce parts as small as 3/8 inches by 1/2 inch or larger than 48 inches by 120 inches.
Following shearing, rolling operations may be used to work-harden or texture sheet metal before bending. Sometimes other post-shearing finishing processes will also be performed on formed sheet metal prior to bending. Bending can be done using either automated press brakes or manual presses such as arbor presses.
Manual bending tends to require more operator involvement and generally produces rougher results but can be significantly less expensive depending on production volume.
Materials in Sheet metal Fabrication
Here are some of the most common materials used in sheet metal services, along with tips on achieving them yourself or ensuring that your manufacturer executes them correctly.
Cold Rolled (Sheet Steel)
At its most basic, cold-rolled sheet steel is simply a term that refers to metal that’s been placed through a rolling mill after having been pulled from an ingot. This type of finish, along with hot-rolled sheet steel, is often associated with lower-quality metals because it causes them to be more prone to dents and scratches.
However, cold-rolled sheet steel actually has many desirable properties when compared to other finishes available on industrial materials—it’s just not as aesthetically pleasing. Still, if you’re looking for cost-effectiveness over the visual appeal, then consider choosing a material in a cold-rolled state.
Hot Rolled (Sheet Steel)
Hot rolled steel is a process where steel is heated to its plastic state and then pressed into a flat sheet. Hot rolling alters physical properties such as hardness, toughness, elongation, elasticity, and plasticity.
This type of surface finish can be used for applications that require great strength or stability. Common uses include structural parts like beams and railings.
It can also be used for items that don’t need to bend much but do need high tensile strength, such as body panels on cars. There are many benefits associated with hot-rolled sheet metal. The cost of labor is low compared to other finishing methods because there’s less time spent preparing before fabrication and after fabrication.
Galvanized Steel
A process that coats steel or iron with zinc, usually via electroplating. Galvanized steel is commonly used for outdoor surfaces and overhangs as a way to protect against corrosion. However, galvanized sheet metal can also be applied to interior environments. The process of galvanizing sheet metal also creates air pockets between layers, which increases insulation and reduces heat transfer.
On its own, sheet metal doesn’t have any inherent insulating properties—that’s why it needs additional coatings like paint or powder coating before being installed. But if you’re planning on keeping your building indoors or outdoors (which most projects do), then galvanized steel provides excellent protection from corrosion as well as from moisture.
Zinc Plated Steel
Zinc plating is an electrochemical process that converts solid zinc into a thin, decorative layer on sheet metal. When done correctly, it creates a durable surface finish that is affordable and maintains its lustrous shine over time. This is one of the most common types of surface finishes used in sheet metal fabrication projects.
It’s also known as hot-dip galvanizing or G90 galvanizing. Both terms refer to finishing steel with molten zinc at temperatures above 360 degrees Fahrenheit; G90 refers to coating sheets at 90 percent adhesion for best performance. In addition to resisting corrosion, hot-dipped galvanized steel features smooth edges and does not require any post-processing before shipping or use in products such as air conditioners or car parts.
Aluminum Coils/Aluminum Sheet
The primary metals used to fabricate sheet metal are stainless steel, aluminum, and copper. The most common surface finish for these metals is a brushed finish. Brushed finishes have grooves machined into them in order to reduce glare and reflectivity.
This reduces eye strain and makes it easier to produce small intricate components. Another advantage of using a brushed finish is that it hides small scratches from handling or shipping. However, a brushed finish can cost as much as double anodizing because an anodizer’s labor costs increase due to longer setup times and smaller tolerances required when brushing.
Anodizing also improves corrosion resistance while brushing doesn’t change corrosion resistance. Aluminum coils come with 2 different types of surface finishes: natural (untreated) aluminum coils and electro-coated (anodized) coils.
Anodizing Sheet/Plate Aluminum
Anodizing is a technique used to increase corrosion resistance and lubricity for aluminum. There are three main types of anodizing: Type I (lowest), Type II, and Type III (highest). The differences between these types lie in the thickness, porosity, and voltage of the oxide layer they produce.
The type of surface finish you get depends on how deep your aluminum will be anodized. For example, if you’re planning to mill or drill into your part after anodizing, it’s recommended that you go with Type III-anodized sheet/plate aluminum. This allows for easy machining while providing protection against corrosion once your part is installed.
Conclusion
Choosing the right materials for your sheet metal fabrication project can make or break the project. In order to achieve the results you desire, it’s important to understand the different types of metal and how to produce them using the most efficient manufacturing process. Let us know in the comments which material you will choose for your next sheet metal fabrication project!
