Processing metal is a highly project-specific process. In order to know which method to finish processing metal is right for your product, it is important to have a firm grasp on the different options available. Last month we covered a few basics. Here are five more. 

Plasma Cutting

Plasma cutting is a very powerful method to finish processing metal. It employs the use of an ionized and superheated channel of plasma to cut even thick metal plate. The plasma is formed by shooting pressurized gas (usually oxygen) through a nozzle within a designated plasma cutter. As the gas reaches the metal being cut, an electric arc is generated between an electrode in the machine and the metal itself. This reaction ionizes the gas, forming a channel of plasma that is electrically conductive. 

The hot plasma melts the metal, cutting through it in its molten state. The method is quick and efficient and even cost-effective. Metals like carbon steel, alloy steel, stainless steel, brass, copper, and aluminum can all be cut by plasma cutting. We offer the service at our Norfolk Iron & Metal and Cd’A Metals locations. 

Polishing

Polishing is one of the final methods used to finish processing metal. It performs the double role of buffing up the appearance of stainless and carbon steel while also improving its sanitation, making it ideal for food processing applications. There are many ways to polish metal, but at the root of the process, the fabricator applies an abrasive surface attached to a flexible backing to wear down any irregularities in the metal.

The precision of the polish is governed by the grit of the abrasive. Smaller values, such as 60 or 80, denote a rougher grit while higher numbers (120 or 180) suggest a finer polish. It is common to use both of these in a succession, starting with the rougher grit. The Norfolk Iron & Metal Group polishes metals in-house. We distinguish our polishes as such: No. 3, No. 4, No. 4 Fine, No. 6, and No. 8 finishes. We also offer specialty finishes. Our Metalwest locations especially carry polished metal supply.

Press Brake

A press brake is a piece of manufacturing equipment, usually designed to be narrow and long, that is used to bend sheet metal. Using a punch that is lowered onto the metal, the press brake secures the sheet in place with a die and then can be used to shape the metal to the customer’s specifications. The method to finish processing metal can be repeated as many times as necessary to achieve the desired shape. 

Press brakes come in many styles and capabilities. They are rated by tonnage, the amount of force they can apply. While 100-300 tons is standard, some units can be as large as 50 feet in length and rated for 3000 tons. Force can be applied pneumatically, hydraulically, electrically, or mechanically. The most powerful press brakes are usually hydraulic. 

Press brakes are used in a wide array of applications, including airframes, furniture, artwork, and automotive panels. The speed of the brake and the material being shaped all play an important role in the amount of pressure applied. Press brakes generally don’t take up too much space, yet they perform quick and accurate work. Here at Norfolk Iron & Metal, we do our press braking in-house.

Sawing

Sawing may be the most fundamental way to cut large metal workpieces into smaller ones. We perform this method to finish processing metal in our Cd’A Metals, Metalwest, and Norfolk Iron & Metal facilities. Sawing uses a saw blade to cut many different kinds of metal, including aluminum, brass, bronze, copper, stainless steel, and titanium. 

There are two primary sawing methods which manufacturers regularly employ: circular saw cutting and band saw cutting. Circular cutting uses a circular blade which spins for clean cuts. Because they are designed with reduced vibration levels and greater rigidity, circular saws cut more quickly and precisely. 

Band saws are long and straight with fine, evenly distributed metal teeth which are designed to be marginally bent. These result in cuts that are slightly wider than blade thickness. More specialized teeth patterns are also available. When band saws are automated, they are ideal for high-volume cutting to finish processing metal.

Sawing has many benefits. The process is ideal for accurately straight cuts and high quality cut finishes. This can reduce the need for subsequent finishing processing. It results in minimal material waste and quick turnaround times without compromising cut quality. 

Shearing

Shearing utilizes two sharp blades to make clean, straight cuts in metal sheets or coils. There are two primary methods to finish processing metal by shearing: using bench shears or a power shear. Bench shears, as their name indicates, can be affixed to a workbench. They are lightweight, small, and easy to operate. Power shears, also called guillotine machines, are more complex in design and are powered by hydraulics or electricity, making them useful for large-scale projects. 

Shearing creates very little waste. The cuts made are exact as upper and lower blades meet, compressing the metal between them secured by a squaring arm. Shearing is beneficial because it doesn’t employ heat in the cutting process, eliminating the risk of melting, burning, or even chipping the metal. When a large volume of simple shapes need to be cut, shearing is often the best option.

The method to finish processing metal does have its limitations, however. It works best with softer metals, including bronze, aluminum, and brass, but is not as effective for harder metals without high-powered machinery. If shearing is mismanaged, the process can deform the metal being cut. We handle all shearing applications with care at our Norfolk Iron & Metal and Metalwest facilities.

There are hundreds of different ways to finish processed steel. Each is unique, offering different pros and cons, and suited for different applications. In the next few months, we will be exploring what each of these processing methods entails. This month we start off with five of the most common: beveling, blanking, hole punching, laser cutting, and leveling.

Beveling 

When it comes to welding, the metal pieces involved need to be prepared so they fit together smoothly. That’s where beveling comes in. Beveling is the process of cutting the butting ends of metal pieces at a diagonal so they fit cleanly together. The slope, cut to the width of the metal, offers greater surface area so the weld is stronger.

In addition to overall greater strength, beveling creates a better bond for two other reasons. The process also reduces the thickness of the metal at the butting endings. The precision and durability of beveling also minimize the risk of cracking in the centerline. It is possible to create an even stronger weld by first creating a double weld. This process reduces the risk of gapping where the metal pieces meet. 

Beveling reinforces a weld in a relatively quick and efficient process. It is important to wear safety gear during the process because of the emissions produced. When you entrust your beveling to the Norfolk Iron & Metal Group, our Cd’A Metals division will take care of it to finish processed steel to your satisfaction.

Blanking

Blanking, sometimes referred to as precision blanking, is a process of punching out blanks from metal coils. The coil is fed continuously between a die and a press, and the piece of metal to be used, the blank, is punched out of the larger sheet. The process is beneficial in its waste management properties. 

Blanking is also a very quick and accurate method to finish processed steel, making it very efficient. It is ideal for specialized parts as the process is very customizable. In the Norfolk Iron & Metal Group, we perform all blanking applications at our Metalwest facilities, and we branch out beyond just steel. In addition to stainless and carbon steel, we also work with iron, aluminum, and copper.

Hole Punching

At Cd’A Metals, another method we provide to finish processed steel is hole punching. It follows a similar process to blanking, using dies and other tools to punch through sheet metal, but the goal of hole punching is to work with the piece with the hole in it, instead of working with the punched-out piece. The dies serve to stabilize the metal, giving the fabricator the power to mold the sheet metal as necessary. 

Punching has its limitations as a way to finish processed steel. Generally metal must be between 25 and 30mm thick for the proper precision to be achieved. The punch weakens and then severs the metal to create the desired hole, and the excess metal falls out of the bottom. Hole punching is used in many applications, including manufacturing, engineering, automotive, textiles, and even pharmaceuticals. It is not limited to steel, also applying to aluminum, iron, brass and copper.

Laser Cutting

We would be remiss in enumerating the ways to finish processed steel if we did not elaborate on laser cutting. As the name suggests, laser cutting employs the use of a small-diameter laser to cut through metal and produce 2-dimensional parts. This can include both plate and sheet metal, but the best results arise when thinner materials are cut as the laser has an approximate maximum cut depth of 25mm.

That being said, with the right amount of power, laser cutters can process just about any material. In addition to stainless and carbon steel, common metals to laser cut include brass and aluminum. Client specifications are programmed into the laser cutter in a series of directions along an X-Y plane known as the G-code. The laser follows these along the machine bed, making precise cuts, even as fine as 0.1 mm.

In an effort to remove waste from the cutting area, the machine may use a high-pressure stream of gas which blows the molten metal out of the bottom of the material being cut. In other applications, the laser may simply vaporize the waste. Laser cutting is most effective for thin sheet materials, requiring very little processing after the fact. The occasional exception is the need to deburr cut edges to remove slag.

Laser cutting is automated, highly precise, and quick, especially on thinner materials. Unfortunately, laser cutting also requires a great deal of power and is initially expensive with high maintenance costs. It can also create dangerous fumes, so the process must be completed with care. If you need laser cutting performed to finish processed steel, our Cd’A Metals and Norfolk Iron & Metal site can take care of it to your satisfaction.

Leveling/Cut-to-Length

Leveling lines is the process of converting coil into sheet metal. The coil is unrolled, leveled, and cut into cross sections. From there, the new sheet pieces can be stacked, packaged, and shipped. It is important that during all of these processes tolerances for error are minimal, adhering closely to customer specifications. Corrective leveling managed during the entire process ensures specificity and compliance. 

When our customers require leveling or cut-to-length services, we manage them at our Norfolk Iron & Metal and Metalwest facilities. The cut-to-length process is one commonly used to finish processed steel, though at some of our locations we can also work with nonferrous material. We specialize in meeting leveling and cut-to-length requirements from 28 gauge to 10 gauge carbon steel, even up to 1/4 inch in our Garland, Texas location. Speak to our representatives about more custom cuts.