Sheet Metal Fabrication
What sheet metal fabrication is, the different processes involved, and how do choose the right process?
Sheet metal fabrication 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 Sheet Metal Fabrication?
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 the process of taking metal sheets and forming them into different shapes using a variety of different manufacturing methods. 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. These different processes can involve cutting sheet metal, molding it, or putting different pieces together.
How is Sheet Metal Being Used?
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 Techniques
Sheet metal, by definition, starts out flat but can be shaped in many different ways to meet many different requirements.
A variety of techniques exist for shaping the material into multi-axis forms that are not made up of flat planes or bent along a single axis. These include hot and cold forming techniques of deep drawing, hydroforming, spinning, and stamping. In many cases these techniques are iterative, shaping the metal by repeating the process several times to change the shape of the metal in increments.
8 Steps of Sheet Metal Fabrication Processes
Design & Drawing
The 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 metal fabrication is most economical when it uses configurations of “universal” tools rather than part-specific tooling. If a single part becomes too complex, consider welding or riveting together parts that can be made using universal tools.
- Because bends stretch the metal, features must stand away from bends to avoid distortion. A useful convention is 4T—four times the material thickness.
- A press brake creates a bend by pressing sheet metal into a die with a linear punch, so the design does not allow the creation of closed geometry.
- Sheet metal tolerances are far more generous than machining or 3D printing tolerances. Factors affecting tolerances include material thickness, machines used, and the number of steps in part production. Suppliers will typically provide detailed information on tolerances.
- A uniform bend radius such as 0.030 in. (industry standard) should be used across a single part to reduce the number of machine setups and accelerate production.
- Where possible, maintain a standard distance of four times the material thickness from bend to edge. This will eliminate the need to remove excess material required to make the bend.
- Welding thin materials can lead to cracking or warping. Other assembly methods are preferable.
- When using PEM hardware, always consider the minimum requirements of the manufacturer for installation locations and material thickness.
- Wall Thickness: Uniform thickness is very important for any geometry. Geometries with more than one wall thickness will require sheet metals of different thicknesses. Therefore, the alignment and orientation of parts may be inaccurate or take time.
- Bend Radii: It is important to keep the inside bend radius of sheet metal at least equal to its thickness. This will help to avoid distortions and fractions in the final parts. Maintaining the bend radii consistently across the part ensures cost-effectiveness and good orientation.
- Bend Allowance and Deduction: Bend allowance is the material needed to be added to the actual lengths of the parts to help develop a flat pattern. Bend deduction is the material needed to be removed from the length of flanges to help get a flat pattern.
- K Factor: K factor is the sheet metal process is the ratio of neutral axis to material thickness. This value changes with respect to the various physical properties and thickness of materials used.
- Holes and Slots Orientation: These factors are also very important. Holes and slots diameter should at least be as large as the thickness of the sheet metal. Also, holes should be reasonably spaced. They should never be too close to the edge of the material.
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 as 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 the 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:
- Laser cutting, which applies a focused beam of energy;
- Plasma cuts using heated gases; waterjet cutting, which applies concentrated streams of water with abrasives;
- Simply machining the sheet metal with drill bits and lathes, or processes like spinning or milling.
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, change 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.
Forming 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:
- Done through a stretcher, a mechanically-operated tool that slowly pulls the metal apart;
- Hammer and dolly, when an object is placed behind the metal, and a hammer hits the opposite side, causing the metal’s surface area to expand and ultimately stretch;
- The English wheel is an anvil-like metalworking tool that extends metal and can create compound curves.
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.
The 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.
- Welding is a familiar process, it is performed to assemble the sheet metal parts, that fuse sheets of metals while adding a filler, CO2 welding and spot welding are some of the welding options which are made use of in the assembly of sheet metal parts;
- A rivet is an easy, economical and permanent way to bind two or more sheets of metal together, one of the biggest advantages of riveting is that your two parts don’t have to be made of the same type of material;
- Blazing is a similar process that joins metals by melting a filler between them rather than melting the sheets, too;
- Structural adhesives are the final method used to join metals either through bonding alone or in combination with another joining method.
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, and 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.
- Sand blasting, which consists of shooting jets of abrasive material at the metal to roughen and clean the surface. Sandblasting is typically used on stainless and carbon steel and is often used as a preliminary step before painting to remove impurities and improve adhesion.
- Brushing is similar to sandblasting in function, but uses abrasive brushes to clean and score the metal surface. It can serve as a final finish on materials like aluminum and stainless steel and is commonly used as an appliance finish.
- Polishing yields a glossy surface and is used on metals like stainless steel, aluminum, and copper. It can serve as the final finish or as preparation for other finishing processes such as plating. It is generally unsuitable for metals that are to be painted because it does not enhance adhesion.
- Powder coating electrostatically applies a dry powder—typically a thermoplastic or thermoset polymer—to the metal surface and then cures it with heat. The process results in surface that is more durable than conventional paint but may not have paint’s aesthetic qualities.
- Plating can be done electrolytically or electroless for a various purposes. It can inhibit corrosion, improve solderability, harden a surface, prevent wear, reduce friction, or aid paint adhesion. Plating processes for sheet metal include:
- Passivation, a cleaning process that prevents corrosion in stainless steels by removing free irons from the surface of the material
- Chromate coating, a conductive coating used on aluminum to protect against corrosion.
- Anodizing, an electrochemical process used on aluminum and other non-ferrous metals that provides insulation and prevents corrosion
- Zinc, a self-sacrificing anti-corrosion coating (applied by galvanizing or galvanealing) for steels and is often combined with a Chromate coating over the zinc
- Nickel, often a cosmetic coating and can serve as a substrate for plating processes that cannot adhere to a given metal
- Tin, a solderable, conductive coating
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 includes:
- How to inspect the finished parts, including which dimensions of the parts will be examined
- When inspections will take place, including in-process checkpoints and final inspection
- The AQL and index values that determine how many randomly selected parts in each lot will be inspected
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 finishing is also verified. If the quality is found OK from all aspects, the piece is cleared for “packing”.
External quality control of the parts
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：
- Changes in the thickness of the material during forming
- Springback after the part is formed
- Distortion of the sheet metal parts
- Quality of the surface and edge of sheet metal parts
Internal quality control of the 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 material physical and chemical properties.
In the process of sheet metal fabrication, its physical and chemical properties should be controlled in the fallowing ways:
- Appropriate intermediate heat treatment and final heat treatment parameters should be specified and the material properties should be strictly required. For the material that is sensitive to internal stress, the stress relief process should be arranged in the forming process;
- Using thermoforming technology to process sheet metal parts with the heating temperature and heating time strictly controlled.
- All sheet metal parts that require intermediate annealing must be strictly controlled before annealing to avoid critical deformation.
- Reasonably arrange the hardness inspection process of sheet metal fabrication parts.
Packing & Shipping
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.
|When||. Components or sub assembly sent to another facility for assembly and integration||. Too bulky to be shipped assembled||. Finish products can be package and shipped economically allowing for good protection|
|. Product is made of modular components||. Easy for end-user to assemble|
|. Too bulky to be shipped assembled / knock down||. Some products can’t be package in a single carton due to geometry, shape, size or weight|
|Pros||. Inventory reduction||. All cartons shipped in complete kits||. Simplified quality control during assembly because finished products are easier to quality check|
|. Logistic cost savings||. Logistic cost savings||. Risk reduction of components missing at end-user|
|. Good packaging quality with limited damage risk during logistic|
|Cons||. Can’t be shipped in bulk to an end-user as it sometimes requires skills to assemble||. Sometimes require skills to assemble, not suitable for all product categories||. In some case, logistic costs are too high due to shape, size and weight|
Engineer the right packaging
|Rules When Engineering Packaging|
|Rule # 1||There are 2 types of packaging options you should consider:|
|2 types of packaging options||Type 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 itself|
|Rule # 2||Type 1 Packaging: The product must be strong enough to support other cartons to be palletized|
|Geometry is continuous and the product must not move inside||Type 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 carton|
|Rule # 3||Determine how you’ll palletize the products and how it will be loaded inside the container or truck|
|Loadability inside truck or containers||It’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 # 4||Once you finish designing the packaging concept, you should confirm 3 things prior to producing packaging samples:|
|Logistic cost validation||1. Validate container load ability|
|2. Validate logistic cost|
|3. Validate packing cost|
|Rule # 5||Test your packaging with samples|
|Drop test validation||Work 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 condition|
Boxes are available as brown, white, or custom printed – each with its distinct advantages and disadvantages.
- 60-100% recycled cardboard
- Less expensive than white or printed
- Easily available in a wide variety of standard sizes and strengths
- Preferred for branding by some and allows for more printing options
- Shows dirt and damage more than brown boxes
- Can also contain recycled material
- Custom printed boxes
Most costly option
- Can be customized inside and out to support your brand
- Can include instructions for the product
- Requires additional lead time and minimum quantities may be required
- Artwork and setup charges for each size of the box and for any changes will be required
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.
- A flute is 1/4” thick with 33 flutes per linear foot, and provides the best cushioning properties
- B flute is 1/8” thick with 42-50 flutes per foot, can resist crushing, and has good stacking strength
- C flute is 3/16” thick with 39-43 flutes per foot, a common choice for shipping
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 BOX||MINIMUM EDGE CRUSH TEST||MULLEN BURST TEST|
|35 lbs||26 ECT||150#|
|50 lbs||29 ECT||175#|
|65 lbs||32 ECT||200#|
|95 lbs||44 ECT||275#|
|120 lbs||55 ECT||350#|
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 (Expanded Polyethylene)Foam
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.
- No odor or taste, food-safe
- Lightweight with a high weight-to-strength ratio
- Very flexible
- Good shock absorption, cushioning, and insulation
- Resistant to water, oil, static, and some chemicals
- Recyclable and reusable
- More fragile than traditional foam
- Deforms easily
- Recycling facilities may be limited for end-user
CustomizedEPS (Expanded Polystyrene) Foam
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.
- Can be formed or molded into a custom shape to protect a part offering a tight fit for sensitive items
- Custom shapes to contain part or molded corners are possible
- Lightweight and stackable
- Very good impact strength and shock absorption
- Low moisture absorption, chemically inert, bacterial resistant, and food safe
- Good insulation and cushioning
- Does not contain CFCs or HCFCs and is recyclable
- Requires lead time for customization
- Additional costs to develop custom design and mold
- Any changes to product or packaging will require changes to EPS mold which will impact the budget and timing
- Brittle and can break into multiple small pieces
- Flammable and can degrade when exposed to UV light
- Recycling facilities may be limited for end-user
- Not biodegradable
Molded Paper Pulp
Typically made of recycled paper, molded paper packaging is available in different thicknesses and can be molded to fit a specific part.
- Can be formed or molded into a custom shape to protect a part offering a tight fit for sensitive items
- Custom shapes to contain part or molded corners are possible
- Very strong with good shock absorption and cushioning
- Less expensive than many other foams and plastic packaging
- Water-resistant, electrically neutral, resistant to temperature changes
- Made from recycled materials, is recyclable, biodegradable, and compostable
- Requires lead time and additional costs for customization and mold design
- Changes to product or packaging will require changes to mold and impact budget and timing
- It may be heavier than other options, increasing shipping costs
- Treatment is required to make it completely waterproof and not just water-resistant
Plastic bubble wrap
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.
- Used to wrap parts or fill voids
- Flexible and suitable for a wide variety of products
- Good shock, vibration, and surface protection
- Inexpensive, lightweight, and anti-static
- Some are more environmentally friendly with pre-and post-consumer waste incorporated
- Air seals can be punctured compromising the cushioning ability
- Recycling facilities may be limited for end-user
- Not biodegradable
Paper Void Fill
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.
- Good cushioning and surface protection
- Can be branded if required
- Compresses so a lot of material is required to provide appropriate cushioning
- Adds weight to the package
- Doesn’t protect against moisture, chemicals, oils, etc
Corrosion protection during shipping
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 and desiccants
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.
Foil vapor barriers
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.
Package and Product Labeling
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 can be marked or labeled with different methods including electrochemical marking, lasers, or screen printing to identify part numbers or add branding or other identifying information
- Your labeling and packaging should support your brand, including boxes, on-product labeling, and possibly other shipping materials
- Knock-down kits should be labeled for easy handling and assembly at their destination
- When multiple products are boxed and shipped together for additional distribution, the external boxes should be labeled to support logistics and inventory management at warehouses
- Different jurisdictions have different requirements for labeling standards so confirm what’s required and work with the expertise of your fabricator
- Some products require permanent markings on the product themselves including products for small children
- Labels shall include traceability # to track design change and enable inventory control according to good practices
Final Thoughts on Choosing Sheet Metal Fabrication?
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!
- QUEST-TECH: A Guide To The Process Of Sheet Metal Fabrication
- Guangzhou Komaspec: Packaging and Shipping Best Practices for Sheet Metal Fabricated Parts
- Proto Labs: Designing for Sheet Metal Fabrication
- Metal Cutting Corporation: Quality Control in the Manufacture of Metal Parts