Sheet metal fabrication is a crucial prototyping and production method that delivers a broad spectrum of metal products used for various applications. In this fabrication process, flat steel or metal sheets are transformed into metal structures and products by cutting, punching, folding, and assembling. Through this technique, any metal can be bent, shaped, or stretched by using cutting tools or by heating.
Subsequently, sheet metal fabrication offers a number of advantages, which is why fabricated products are used in various industries. Depending on the materials and specifications, sheet metal fabrication delivers the following benefits:
These metal products can be used as components for electronics, aerospace, heating, ventilation, and air conditioning (HVAC), and several other industries, including:
This article will walk you through the step-by-step process of steel metal fabrication, the materials used, and the techniques employed.
Sheet metal fabrication entails the multiple processes of altering the shape of metal sheets to generate the desired components and products. Manufacturers use this fabrication method to modify a variety of materials, such as:
These materials for sheet metal fabrication typically come in gauges with 0.006″ to 0.75″ (0.015 to 1.905 cm) thickness. Materials with thicker gauges are best used for fabricating heavy-duty parts with strenuous applications, while thinner ones are more pliable and used for applications that require components with more complex shapes.
Before diving into the step-by-step process of sheet metal fabrication, it is crucial to learn and understand the diverse techniques fabricators employ. This section will also include some of the metal fabrication tools used in the following techniques.
Depending on the materials used, sheet metals that underwent fabrication vary in the features they possess. For example, some are known for their robust strength, ductility, and corrosion resistance, while other metal products are lightweight and malleable. Here are the basic guidelines for the metal fabrication process.
The fabricating process starts by finalizing the design of the desired product. In this step, clients usually submit their final blueprints to manufacturers before the actual fabrication process. This blueprint should also include the specifications required to manufacture the metal product.
During the second step, flat sheet metal blanks are cut out from their large coils in preparation for the subsequent steps. The sizes of the blanks vary depending on the specifications of the final product design.
Also a cutting technique, punching produces holes of different shapes and designs to the sheet metal blanks. This step is typically completed using a punching machine. However, some fabricators use laser-cutting technology to achieve holes with optimum precision.
With a Press Break machine, the sheet metals are bent at different places and angles in consideration of the design specification. In this step, the bends are created in sequence to ensure that the current bending will not affect the execution of the following bends.
After fabricating all the necessary components in the previous steps, assembling the workpieces comes after. Finally, a welding machine is often used to combine the pieces to create the final product. Other times, O2 and spot welding are alternatives used to assemble these metal parts.
In this process, the assembled product undergoes a series of finishing techniques to achieve the desired physical appearance of the metal piece. Finishing includes cleaning, coating, painting, and galvanizing. In addition, heat treatments may sometimes be applied to products that are meant to withstand unique working environments.
This step focuses on verifying if all design specifications are met during the metal product fabrication. Here, manufacturers test the product to guarantee optimum quality. The product will be tossed back for corrections if a functional error is observed. Usually, metals with defects undergo welding or a special straightening process to remove blemishes and fix their defects. Once the metals pass the specification requirements, they will be qualified to move to the final step.
Once the quality has been checked, fabricators will send the finished products to the final step for packing and shipping.
Over the past 40 years, Farris has grown into becoming one of the leading fabrication and finishing facilities in the United States. With over 230 employees and 200,000 square feet of combined working space for all three locations, our company provides superior customer service, innovative manufacturing, and incomparable product quality.
We offer the following capabilities for our custom fabrication services:
Fabrication at Farris is limitless. Because of the availability of tools, equipment, and ability, we guarantee to complete any custom metal fabrication project. Moreover, our extensive engineering, programming, machining, and welding knowledge allows us to create metal parts of diverse shapes and sizes.
Because we believe that our machinery mirrors our capabilities, Farris has invested in the latest equipment and technology for fabricating metals. As a result, we can achieve metal fabrication with outstanding precision and efficiency through various laser-cutting equipment. Additionally, we have 15 press breaks that enable us to bend and form metal of varying thickness and size. We can also cut and shape metals for multiple uses, thanks to our top-notch mills and lathes.
Farris is ISO 9001:2015 certified. Because of this, we are driven to maintain consistent and excellent services by providing metal products that are meticulously fabricated to perfection.
When you partner with us, we guarantee to work with you from start to finish. Our experienced engineers and specialists are equipped with outstanding skills to guide you on the most efficient methods to manufacture your products.
Apart from our fabrication services, Farris offers a wide range of machining, mechanical prototyping, laser cutting, kitting and assembly, metal forming, welding, powder coating and painting, and pop displays manufacturing.
Contact us to learn more about what we can do for you!
What sheet metal fabrication is the different processes involved, and how do choose the right process?
Sheet metal fabrication techniques is a comprehensive cold working process for sheet metal (usually below 6mm), including shearing, punching, bending, welding, riveting, die forming, and surface treatment. The characteristic of sheet metal fabrication is that the thickness of the same part is the same.
What is the Sheet Metal Fabrication Process?Greg Paulsen: In sheet-metal fabrication, parts are formed from metal sheets by punching, cutting, stamping, and bending. Sheet-metal parts are known for their durability, which makes them great for a wide variety of applications. Parts for low-volume prototypes and high-volume production runs are most cost-effective due to large initial setup and material costs.
Sheet metal fabrication is a process of transforming flat sheets of metal into finished products or components through a series of manufacturing processes. Unlike other types of manufacturing techniques, sheet metal fabrication involves a number of different processes that manipulate and mold sheet metal in a variety of ways. The raw materials used for sheet metal fabrication are typically metals such as steel, aluminum, brass, copper, and titanium. The process involves cutting, bending, shaping, and assembling sheet metal to create various products.
Sheet metal fabrication is used in a wide range of industries, including automotive, aerospace, construction, and electronics. It requires skilled technicians and specialized equipment to ensure that the metal components are manufactured to the required specifications and meet the required quality standards.
Metals used in sheet metal fabrication processes can be derived from any common raw stock material—stainless steel, aluminum, iron, bronze, copper, carbon steel—nearly any type of ferrous or nonferrous metal. Which metal is selected depends mainly on its properties—corrosion resistance, tensile strength, flexibility, hardness, and conductivity required for the intended application.
Sheet metal is cut, stamped, punched, sheared, formed, bent, welded, rolled, riveted, drilled, tapped, and machined. Hardware can be inserted into sheet metal components. The components can be brushed, plated, anodized, powder-coated, spray-painted, silk-screened, or otherwise marked. And, of course, parts can be riveted, screwed, or welded into complex assemblies.
Sheet Metal Fabrication TechniquesThere are many different techniques used in sheet metal fabrication. Here is a brief explanation of each of these techniques:
Punching, stamping, laser cutting, water jet cutting, and chemical etching are all popular techniques used in sheet metal fabrication. Punching and stamping involve using a punch and die set to create holes or shapes in the sheet metal. Laser cutting and water jet cutting are both methods of cutting through the sheet metal with a high-powered laser or water jet. Chemical etching involves using chemicals to selectively remove material from the sheet metal to create a pattern or shape.
Click for the chart of tensile strengths for aluminum and stainless steel to compare with mild steel
8 Steps of Sheet Metal Fabrication Processes Design & DrawingThe very first step in the process of sheet metal fabrication is to create a design of the final product, the design for sheet metal fabrication has its own criteria, which differ from those of other production processes. The more that’s known early in the design phases about a part’s features and functions, the sooner a manufacturable design will be finalized.
Sheet metals are produced in large coils. And, those coils are then cut into the desired length so as to create the small-length rectangular sheets. Further, the manufacturers of these rectangular sheets supply them to the sheet metal fabrication industries for their use.
The sheet metal fabrication start with a rectangular metal sheet and, based on the customer’s part design, the material is cut to size. Cutting is the process of cutting flat sheet metal blank out of a large sheet, the blank size is according to the requirement of the final product’s design.
There are various methods for cutting sheet metals, but only are two different types: shear and non-shear.
Shearing was long the primary way to cut sheet steel but has now been replaced by faster, more precise methods.
Shear cutting is generally used for nonindustrial components and end products. It includes such processes as cutting, shearing, and blanking. The basic process itself, cutting, uses a single blade to cut through the material. Shearing is, essentially, a similar action to scissors. Upper and lower blades cut through a straight line. One blade remains stationary while the other cuts through the metal. Blanking is a robust hole-punching process that cuts out cookie-cutter-like designs from metal.
Non-shear cutting is a process used for integral parts and components found in large-scale industrial applications and products. The process requires precision and accuracy accomplished through a variety of methods:
Thousands of custom sheet metal products with any shapes, holes, countersinks, and counterbores can be created using cutting-edge CNC punching equipment.
Punching is a cold-forming method that transforms flat metal blanks into various shapes, it is also called stamping. The process uses a tool and die, which, when impacted, changes the form of the metal through the use of shear pressure.
A punch press can be used to punch and die sets to cut metal. This is particularly effective for cutting relatively simpler parts than would be cut with a laser or waterjet. Because it can operate at hundreds of strokes per minute, a punch press can make suitable parts quickly. Punching can also be used to make holes or other cutouts in parts. Combining punch and laser cutting allows the creation of a complex flat pattern with size-limited stamped features.
FormingForming is a sheet metal fabrication process that bends or deforms the material into the desired shape. Unlike cutting, which subtracts material, forming reshapes the material without losing its mass. Forming processes include stamping, bending, stretching, and roll forming. Methods such as stamping utilize a set of dies that press designs into the metal to create the desired form.
Sheet metal is bent at various places and angles as per the requirement of the design specifications. Most metals can be bent along a straight axis using a variety of presses. These bends are made in a sequence that any of the bends may not make any hurdle in the execution of the next bend. The shapes of bends can range from gentle curves, like those along the vertical axis of a steel can, to sharp corners at angles above, below, or right at 90 degrees.
Bending is accomplished through press brakes (or sometimes by hand). Press brakes are used to create these relatively sharp bends. Rolling and forming methods produce open or closed single-axis curves in a continuous bending operation. The process can create custom forms, V-bends, and U-bends.
Stretching, as the name suggests, lengthens the metal by pulling it apart without separation. Various methods include:
Finally, though similar to bending, roll forming is a process that allows the entire metal sheet to pass through a pair of rolls to form the material into the desired coil shape.
Curling/Hemming is a sheet metal forming process that’s used to smooth out the otherwise sharp and rugged edges of sheet metal. Sheet metal often contains sharp edges with “burrs” after it’s initially produced. Curling is a forming process that involves de-burring sheet metal to produce smooth edges.
Hemming/Curling involves rolling the edge of a metal shape to provide a smoother, stronger edge. Hems can be open, leaving an air space within the bend, or closed, in which the folded metal is pressed tightly against itself. Curling produces a rounded edge to a piece of metal, also called a barrel hem. This can be used to simply eliminate the sharp edge or to serve a specific operational function as in the case of a door hinge where it holds the pin around which the hinge rotates.
Sheet metal may also be ironed to achieve a uniform thickness. Most aluminum cans, for instance, are made of ironed aluminum. In its raw state, the aluminum sheet metal is too thick for beverage cans, so it’s ironed to achieve a thinner, more uniform composition. Ironing involves the use of a punch to force sheet metal between two dies.
A lesser-known sheet metal forming process is hydroforming. Like deep drawing, hydroforming involves stretching the blank over a die. So, what’s the difference between hydroforming and deep drawing? The key difference between these two processes is that deep drawing requires multiple draw reductions, whereas hydroforming is performed in just one step.
AssemblyThe Assembly of Components is the final step in the process of sheet metal fabrication, this step involves the assembly of all of the components. Once the metal has been formed or cut into the required shape for an application, it may require being fused or joined together either by welding, brazing, riveting, or adhesives.
After the assembly of sheet metal parts, the final product is sent for the finishing process, and parts and components undergo finishing processes to enhance the end product. Finishing is done to provide a required appearance as well as other desired physical properties as per the requirement. It may be a simple cleaning. It may also include some other processes like coating, painting, galvanizing, etc. Some special heat treatments may also be performed to provide some special properties needed for the product to survive in a special working environment, application to improve material properties such as corrosion resistance or increase conductivity, and others that are applied for aesthetic reasons.
In some cases, finishing serves both purposes. Some treatments are simply alterations to the metal surface itself; others consist of another material or process that is applied to the metal.
When the time comes to determine whether the finished product meets your specifications, at Metal Cutting we generally recommend a final inspection using an Acceptable Quality Level (AQL) sampling plan.
A sampling plan is an important part of quality control, allowing a manufacturer to inspect a portion of a product lot to determine if the entire lot meets the customer’s quality requirements.
Especially for small metal parts and other high-volume production, a sampling plan is far faster and less expensive than inspecting every part. Yet, a sampling plan still provides a statistically valid and reliable indicator of whether a lot is defect-free.
The sampling plans typically include:
The quality of sheet metal fabrication parts is generally divided into two aspects: external quality and internal quality. External quality control mainly means that the accuracy of the geometric size and shape of the parts meet the requirements of the drawing and no damage or pollution on the surface, and no burrs on the edges, etc. Internal quality control, however, mainly refers to controlling the physical and chemical properties of materials after the parts are formed.
After performing all of the steps to produce a sheet-metal product, the final product is now checked to ensure optimum quality. All specifications are verified to match exactly the given design. If any error is observed, the piece is rejected and sent back for correction. The quality of the finishing is also verified. If the quality is found OK from all aspects, the piece is cleared for “packing”.
Except for the errors of the process equipment itself, there are four main factors that can affect the geometric size and shape accuracy of sheet metal parts：
When the material is made into sheet metal parts through plastic deformation, its physical and chemical properties must satisfy the design requirements, because these parts are designed on the basis of the material’s physical and chemical properties.
In the process of sheet metal fabrication, its physical and chemical properties should be controlled in the following ways:
Quality control doesn’t end when the parts come off the production line and pass inspection. The final step of the quality program is packing the finished components so that they are properly protected when shipped and arrive safely at their destination.
The last step in the fabrication process. The final product is packed and shipped to the client or the place of its use. Package design is an important part of the engineering process and should consider the entire logistics cycle and the shipping requirements.
It’s possible to package similar parts together in bulk if the parts will not tangle and potential surface damage from contact will not impact their usability.
Extra steps are necessary when the parts shouldn’t be in contact during shipment. Using spacers or padding made of foam, paper, wood, or other materials is necessary to prevent any scratching or finish damage. Parts that nest together may only require paper between them while stacking parts need cardboard or plastic to separate them.
Parts with hardware may require additional padding to protect the hardware and adjacent parts in a package. Sharp edges may also require additional protection.
A knock-down or knock-down kit is a form of shipping that packages all the parts together to be assembled elsewhere.
This is a common option for automotive, rail, electronics, and furniture and is sometimes used as part of import tax strategies.
Semi-knock-down kits are also possible where some components are already assembled but not all.
Parts can be efficiently shipped in flat sheets if they are being assembled elsewhere.
How you package assembled parts will vary based on their destination. They may or may not require end-user packaging depending on the next stage in your logistics cycle.
End-user packaging should support your brand and meet all destination labeling requirements in addition to fully protecting the product during transport. Your marketing and legal team should be important partners in this process.
End-user packaging of assembled parts should also include any instructions or other printed inserts for the customer.
Custom containers are the only option for some products based on size, weight, or dimensions.
5 rules
Rules When Engineering PackagingRule # 1There are 2 types of packaging options you should consider:2 types of packaging optionsType 1: The product supports the packaging. In this case, the carton is sole to protect the product surface during shipping Type 2: The packaging supports itselfRule # 2Type 1 Packaging: The product must be strong enough to support other cartons to be palletizedGeometry is continuous and the product must not move insideType 2 Packaging: The product must not move once packaged and the carton or insert must be strong enough to support multiple cartons when products are palletized *See section 2 of this chapter to see different methods of protecting the product inside the cartonRule # 3Determine how you’ll palletize the products and how it will be loaded inside the container or truckLoadability inside trucks or containersIt’s best to design packaging so it is easy to load and unload by forklift *Keep in mind that the container door height is lower than the container internal height.Rule # 4Once you finish designing the packaging concept, you should confirm 3 things prior to producing packaging samples:Logistic cost validation1. Validate container load ability 2. Validate logistic cost 3. Validate packing costRule # 5Test your packaging with samplesDrop test validationWork with your freight forwarder or carrier to drop test your packaging and ensure the product will not be damaged across the logistic journey *Your ultimate goal should be for the end user to receive the carton in perfect conditionBoxes are available as brown, white, or custom printed – each with its distinct advantages and disadvantages.
Brown boxes
Carton strength
Boxes are made of corrugated paper which uses s-shaped paper flutes between linerboard paper to create its strength and structure. The thickness and number of flutes per foot impact the strength of the box.
The industry uses the Mullen bursting tests and edges crush tests to establish guides for boxes.
The Mullen burst test standard is often used by those who are concerned about damage during handling throughout the logistics chain.
The edge crush test helps understand how the box will hold up when stacked or palletized.
To understand how to interpret these standards, an edge crush test of 26 ECT means it can withstand 26 pounds of pressure on the edge of the carton.
A Mullen burst test score of 150# means it can withstand 150 pounds per square inch of force applied to the face of the carton.
Single-wall corrugated boxes
MAXIMUM LOAD PER BOXMINIMUM EDGE CRUSH TESTMULLEN BURST TEST35 lbs26 ECT150#50 lbs29 ECT175#65 lbs32 ECT200#95 lbs44 ECT275#120 lbs55 ECT350#There are a lot of different options when it comes to packaging materials. Physical damage can occur during different stages of transport, loading, and unloading. However, your package may also be exposed to moisture, elements, and different chemicals which can all impact your packaging material choices.
EPE foam (expanded polyethylene foam) has a low density and is semi-rigid with closed cells.
It’s commonly used for cushioning and impact absorption.
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Disadvantages
EPS foam (expanded polystyrene) is a white, rigid foam that can be custom formed to suit the needs of a part. It’s produced from small, solid polystyrene beads and has a closed-cell structure.
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Disadvantages
Typically made of recycled paper, molded paper packaging is available in different thicknesses and can be molded to fit a specific part.
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Disadvantages
Plastic bubble wrap is made from rows of cells with air between layers of polyethylene. Bubble sizes can vary based on the needs of the product, including larger “air pillows” to fill large voids.
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Packing paper, like bubble wrap, can be used to fill voids. It’s typically used on the top and bottom of boxes to provide cushioning to the product inside.
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Disadvantages
Proper packaging can help prevent corrosion should your sheet metal fabricated parts be exposed to any corrosive elements.
It’s a good investment for parts that are sensitive to corrosion and will be transported in conditions that expose them to moisture, chemicals, or significant changes in temperature or humidity.
There are several options:
Bags can be used to act as a barrier to stop moisture exposure for the parts. The bag material will vary based on the parts and the shipment exposure and can include antistatic bags to protect from electrostatic discharge.
Silica gel or activated clay are common choices for desiccants to control humidity levels.
For large containers, desiccant strips are often hung inside.
Parts that are prone to surface damage can be packaged using a water vapor-proof foil barrier that is vacuum-sealed.
Prior to being placed into the foil package, the material is often used to cushion the part, and a desiccant is enclosed.
It’s also possible to include a humidity indicator card inside a component of the packaging that can be opened and checked for humidity levels periodically during shipment without exposing the part itself.
This form of packaging is a best practice for parts that require very low humidity during shipment and is often used for ocean transport.
How you label your product will vary based on several factors, including the type of product and the geographical markets you’re shipping into.
Sheet metal fabrication is a science and an art. Its extensive range of nuances and techniques makes it important for a skilled metal fabricator to handle every project. Since you know the sheet metal design basics, let a professional service take care of the rest!
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