A Plasma Cutter Perfectly Explained

A Plasma Cutter Perfectly Explained

In the world of welding or grinding, you may frequently hear the commonly coined term plasma cutting. Plasma cutting gets its name by its use of propelling a high pressured jet of hot gas known as plasma. This plasma up to 40,000˚F exits through the nozzle and cuts through various metal materials. Plasma cutting can be used for both automotive and construction purposes, as well as scrap metal recycling and metal fabrication shops.

To perform successfully, not only do you need a plasma cutter, but you also need to know how the plasma cutter works. Knowing how a plasma cutter works will help you know how to use a plasma cutter. Smooth quality cuts from your plasma cutter will reduce the amount of work spent on cleaning up and smoothing your initial cut.

What is a Plasma Cutter?

In order to engage in plasma cutting, you will need a plasma cutter. A plasma cutter is a piece of equipment used to cut various types and thicknesses of metal materials by using electrically charged compressed air through a small nozzle opening. The materials best suited for plasma cutting are metal materials such as steel, brass, copper and aluminum.

A plasma cutter will need access to an air compressor or compressed gas. The air compressor or tank is what provides the plasma cutter with the compressed air, argon, nitrogen, oxygen, etc. needed for creating plasma to cut through the material. If you do not have an air compressor, some plasma cutters have a built-in air compressor. Make sure you have access to an air compressor, compressed gas source or a plasma cutter with built-in compressor before you begin.

The type of plasma cutter you need can be determined by your project size as well as the thickness of the material in which you are cutting.  These factors, as well as the type of industry in which you are cutting will determine the type of plasma cutter best suited for the job. Before determining the type of plasma cutter you need, it is important to know the essentials within this piece of equipment.

Components of a Plasma Cutter

Components of a Plasma Cutter

If you were to dismantle a plasma cutter, you would find these necessary tangible and intangible components: compressed gas, electrode, shield gas, and nozzle; and no component is more important than the other. They are all required in forming a safe, functional plasma cutter.

The compressed gas is what makes plasma plasma. Without compressed gas, you would not have plasma. Compressed gas needs to mix with electricity in order to create a state of matter known as plasma. This compressed gas becomes hot enough to cut through metal materials, which is what makes plasma cutting so effective.

The electrode is the component used for creating the electrical arc. The electrical arc is required in plasma cutting because the compressed gas needs to reach an ionized temperature for penetrating metal. Without the electrode, the compressed gas would not become ionized; therefore, not reaching a temperature high enough to cut through the material.

Shielding gas is a gas that is released from the plasma cutter to keep the ionized plasma gas contained to the area it is cutting. It is like an invisible barrier. Without this shielding gas, the plasma would not be contained. This means the cut that you just made using your plasma cutter has spread to an area larger than intended, essentially destroying your total project.

The final component to a plasma cutter is the nozzle. Most plasma cutter nozzles are made from copper. Copper can withstand the extreme heat from the plasma. In addition to thermal conductivity, copper nozzles can also be corrosion resistant.

Whether you are a professional or a hobbyist, knowing the components within your plasma cutter can help you determine the right type of plasma cutter for your job.

Types of Plasma Cutters

There are various plasma cutters available to fit fabrication projects both big and small. You may be wondering how much is a plasma cutter? The cost of a plasma cutter can depend on different variables, such as the size of its electrical requirement and its amp wattage. Low-end plasma cutters can be as low as under $200 and top out at nearly $10,000. Cheaper plasma cutters require a lower electrical requirement, while more expensive models have a higher voltage and amp output.

Plasma cutters can be powered by either a standard three-prong electrical plug with 110 – 120 volt power outlet or up to a 220 – 240 volt electrical current. Determining your home or workshop’s electrical accessibility may determine the type of plasma cutter you need.

Types of Plasma Cutters

A smaller plasma cutter can be powered using a standard three-prong electrical plug with 110 – 120 volt outlet. However, a smaller electrical outlet will yield a smaller electrical output, resulting in a less thick material allowed to be cut.

Large plasma cutters are best utilized in fabrication shops where large material and equipment are used for stationary plasma cutting. For example, computer numerical control (CNC) shops use computer controlled robotics to operate large equipment during production. This equipment includes the plasma cutter. These large plasma cutters can cut through material up to 6 inches thick!

Most commonly used are small plasma cutters. These plasma cutters can be found in most automotive or construction sites where the nature of metal cutting can be fast-paced with a wide range of various applications. Small plasma cutters also include hand held plasma cutters and can cut through material 1.5 inch-thick or less. These plasma cutters are also referred to as cut 50 plasma cutters because they draw 50 amps of electricity. This type of plasma cutter is ideal for standard plasma cutting, as 50 amps usually yield around ½ inch thick cuts.

In addition to plasma cutting, does your job or hobby also include welding? You may want to look into a welder plasma cutter combo. This combination of welding and plasma cutting will give you the option to tackle both jobs with half the equipment. Less equipment not only means less space being occupied, but also less equipment to clean, maintain, and setup. Without having to go between two pieces of equipment during your project, you will be able to produce your fabrication in less time.

Some plasma cutters are capable of going between functionalities, such as hand-held or automated, giving you the option to table cutting as well as localized cutting. If table cutting is a possibility, make sure you have a proper plasma cutting table to withstand the heat from your plasma cutter.

Accessories

There are many accessories that are not only convenient, but also necessary in producing a safe and effective cut with a plasma cutter.

These are some of the best sought after accessories:

  • Plasma cutting table
  • Eye protection, such as plasma shades or plasma goggles
  • Electrical extension cords
  • Plasma cutter cover
  • Replacement consumable parts kit (nozzles, O-rings, electrodes, etc.)
  • Plasma cutting guides

Plasma Cutting Table

CNC Plasma Cutting Table

OUR RATING: 

A plasma cutting table is a necessary accessory for table plasma cutting. A plasma cutting table will ensure that you have a surface that can withstand the extended heat from your plasma cutter. An insufficient plasma cutting table is dangerous as the heat from the plasma cutter can easily burn a surface that is not equipped to withstand excessive heat. Some plasma cutting tables are designed specifically for CNC or computer aiding cutting to which they may include additional accessories to connect to many plasma cutters.

Additionally, some plasma cutting tables are designed for use with water below the cutting surface. This water can assist in catching both sparks and slag as the plasma cutter takes care of its given task. Certain types of metals are not to be cut over water and should only be cut dry but when cutting a material that can be cut wet it is proven that the water can assist with cooling the material that is being cut.

Plasma Cutting Shades or Goggles

Miller Electric Shade 5.0 Welding Safety Glasses

OUR RATING: 

Another accessory that is imperative for safety is eye protection. Unlike welding where the arc from the weld is vividly visible for extended periods of time, a plasma arc is virtually unseen, as it is within the nozzle of the cutter itself. The location of the arc prohibits you from looking at it the way you would need to look at a weld arc. A welding helmet may create too dark of visibility, preventing you from seeing the cut you are making. Therefore, plasma shades or plasma goggles are sufficient eye protection for proper visibility and protection.

Electrical Extension Cords

Electrical Extension Cords

OUR RATING: 

Depending on your electrical accessibility, you may need to purchase a 110 volt or 220 volt welding extension cord to provide safe and adequate electricity to your plasma cutter.

Plasma Cutter Cover

Hypertherm 127219 Powermax45 Dust Cover Viny

OUR RATING: 

One of the best accessories you can purchase to lengthen the lifespan of your plasma cutter is a plasma cutter cover. These covers are not only affordable, but they are also an easy way to ensure your plasma cutter is taken care of. A plasma cutter cover will keep dirt, dust, and other particles from entering the housing of your plasma cutter. Keeping these materials out of your cutter by using a plasma cutter cover will allow your plasma cutter to work properly and efficiently. This prevents the plasma cutter from overworking. Overworking will add extra obsolescence to the overall lifespan of the plasma cutter, shortening its longevity.

Replacement Consumable Parts Kit

Plasma Electrode Tips Nozzle Extended Shroud Shield Cup Kit Fit CUT

OUR RATING: 

Regularly you will need replacement consumable parts depending upon the frequency of use for your equipment. For efficient plasma cutting, keep a replacement parts kit on hand at all times. This kit should have the sufficient consumable parts needed to replace a part that will break over time. Whether it is the nozzle, O-rings, electrode, or even silicone lubricant, having these replacement parts on hand will cut down on time wasted by leaving the job or project to purchase the replacement.

Plasma Cutting Guide

Hypertherm 027668 Plasma Circle Cutting Guide

OUR RATING: 

Plasma cutting guides vary for the purposes of the tasks at hand. Some guides are specifically for cutting circles while others are specifically designed for cutting straight lines. Some models of these accessories are designed for more of a free hand approach but may contain rollers to ensure that you keep a proper height above the surface of the materials while guiding across it. Some of these devices are specific to the torch manufacturer while others are more universal and can even be used for other tasks besides plasma cutting.

Manufacturers

From big to small jobs, there are many plasma cutter manufacturers to choose from that fit the bill. Some manufacturers have additional accessories to choose from to make a quick “one stop shop” when it comes to purchasing your plasma cutter.

Lotos

Lotos LTP5000D 50Amp Non-Touch Pilot Arc Plasma Cutter

OUR RATING: 

Whether you are welding, grinding or cutting, a Lotos plasma cutter will have the specifications you need for a successful project. Lotos offers a variety of plasma cutters from small voltage to large. Some Lotos plasma cutters also feature a welder plasma cutter combination, giving you the option to alternate between welding and cutting. Additionally, Lotos offers various warranty options to purchase. Manufacturer’s warranties are a sensible purchase to make, as you never know what issue may come up with your equipment.

In addition to a manufacturer’s warranty, Lotos also features a user’s manual on their website for each piece of equipment, giving you a quick reference point for the plasma cutter you have.

Miller Spectrum

Miller Spectrum 625 X-treme Plasma Cutter

OUR RATING: 

If versatility, portability and affordability are what you are looking for, then a Miller Spectrum plasma cutter will meet all your needs. Miller Spectrum plasma cutters are designed to successfully cut steel material up to 7/8 inch thick, and aluminum material up to 5/8 inch thick. 

Miller Spectrum also has an assortment of plasma cutting accessories to choose from. These available accessories make choosing your plasma cutter quick and easy.

In addition to the products offered by Miller Spectrum, there is also a wide variety of welding, grinding, and cutting resources available to assist in your project. These resources include safety precautions, frequently asked questions, training materials, and forums; all of which can help you produce a safe and effective cut.

Hypertherm

Hypertherm Powermax 65 Hand System - 25 ft Lead

OUR RATING: 

Most plasma cutters produced by Hypertherm are highly regarded due to their versatility. Many of these units have the ability to be hand-held but also easily converted to automated cutting through a vast array of accessories.

Another factor that makes the Hypertherm a great option is the assortment of consumable styles to include multiple different angles of torches. Hypertherm also has many distributors across the United States, Canada, and Mexico so purchasing consumables in those locations can be done at a local store as opposed to online shopping. Nearly all replacement parts and consumables can be purchased online if one of those distributor locations is not practical.

Hypertherm has been a major contributor to the cutting industry for 50 years through plasma, laser, and waterjet cutting. With the name and reputation on the line, Hypertherm provides a 3 year warranty on most of their plasma cutters and a 1 year warranty on many of their torches and leads. There are exceptions to this warranty but Hypertherm does build a product that they choose to stand by.

 When searching for a plasma cutter there are many factors to consider to include the types of materials to be cut, the location of use, the power and gas supply available, etc. Once you have purchased the correct machine for the task it should last years with proper care and maintenance. After the initial investment, purchasing the correct consumables can keep your maintenance cost down as it can prevent additional damage to the equipment.

Maintenance and Cleaning

No one wants to purchase a piece of equipment only to have to replace it after just a few uses. In order to extend the lifespan and longevity of your plasma cutter, proper maintenance and cleaning is essential. Not only shortening the lifespan of the equipment, neglecting a plasma cutter will also lead to poor cut quality. Each manufacturer recommends inspections and maintenance to equipment at predetermined intervals.

Most manufacturers recommend inspecting the torch tip, electrode, the shield cup, and air pressure before every use. Additionally, any time that the cutting speed has slowed down noticeably, the tip and electrode should be inspected as they are likely the culprit. For cleaning the torch, a simple cotton swab and hydrogen peroxide can clean off the part.

Maintenance and Cleaning

During inspection of the nozzle and electrode you should be inspecting for a perfectly round orifice in order to get the most optimal cut. If these consumable parts are not matching the manufacturer recommendations they should be replaced before more damage occurs. Neglecting to replace the nozzle could result in needing to replace the shield cup prematurely causing adding expenses to the maintenance of the equipment. Most manufacturers’ consumable parts kits cost between $15.00 and $30.00.

At 3 month intervals the regulator and hoses should also be inspected to ensure no cracks or leaks are present. At the same time you should also inspect the torch body and attached cabling. If any cracked hoses or cables are found then they should be replaced immediately to ensure proper tool operation.

All inspections should take place with the power disconnected and should take place more frequently in harsh conditions.

During the use of the equipment and after completing a cut, you may notice an abundance of slag on the tip of the torch or even inside the shield. This can cause the nozzles and other components to overheat and even wear out quickly. Cleaning out the slag periodically during use and before storing the equipment will ensure it is in proper order before continuing or before the next use of the equipment.

If using an air-compressor or “shop air” it is recommended to inspect that system regularly as well to include a water separator or air dryer in-line with the plasma cutter. While most plasma cutters have a built in separator, any water that gets in the air stream can cause the arc to not be reliable and less effective.

During the use of the equipment

If the plasma cutter is not functioning properly it is key to confirm that the torch has been reassembled correctly, that the gas flow is appropriate for the machine and that the tool was properly cleaned. Neglecting any one of these can directly impact the performance of the equipment.

While consumables can be purchased from aftermarket locations, it is important to ensure that the consumables you use are meeting the specifications of the original equipment manufacturer or the performance of the tool may be degraded. Most O.E.M. websites will provide local dealer information so that you can ensure you are purchasing the correct consumables for your product.

Conclusion

As both a hobbyist and a professional, those seeking to cut materials can find the plasma cutter as a quality tool to make that task easier. Many of those find the plasma cutter to be the fastest and most efficient way to cut their materials. With proper maintenance you can not only cut materials quickly but also precise enough to limit the amount of extra work to clean up your materials.

Over the last decade the prices of plasma cutters has dropped to a level where more hobbyist can enjoy the performance of a plasma cutter. Also during this time period the precision of these tools has improved with smaller nozzles and thus a thinner plasma arc. The thinner plasma arc is making the tools produce nearly laser precision which had previously only been achieved by other cutting methods.

After gaining experience and proper technique, a hand cut using a plasma cutter will be very efficient in cutting your materials. For most robust projects or where more precision is needed, add-ons or a CNC machine can be programmed using the near laser-like cutting tool to produce cuts that are reliable and accurate.

Leave a Comment: