How to Use a Plasma Cutter

How to use a Plasma Cutter

 

Hand-held plasma cutters are among the most appreciated tools for constructions workers, auto repair services, home improvers, and other people who work with various kinds of metals. This type of cutting beats shears and saws since it offers precision, power, and doesn’t require any preheating.

When you read about plasma cutters, it seems as if there isn’t anything hard about operating a manual unit. It appears straightforward. In fact, it looks so simple, that you are tempted to drag it out the box and start using it immediately. However, there are a few things you might want to consider before you get into the process, otherwise, you might end up with some unfortunate consequences.


Read the Manual

Are you rolling your eyes now? Not all plasma cutters are created equal and unless you have vast experience in using many different plasma cutters, you need to spend at least 5 minutes reading the operating instructions. You’ll definitely find something you didn’t know before. Reading the manual can make a difference between a precise cut and a ruined material.

If this tip shocks you in any way, then perhaps you’re not ready!  you should head on back to our recent blog post on how Plasma cutters actually work!

Everyone else, read on!


Adjust the Settings

While there are automatic plasma cutters, sometimes you might be faced with one that requires you to adjust the settings manually. The air pressure should be set at about 60 psi. The most important setting is the voltage. Many people believe that using any tool on its highest setting will offer the best results. Such is not the case with plasma cutters. When you use the highest setting, you’ll get erratic and not precise cuts which might be a disaster for thin metals.

You need to check out the metal before making the setting. For example, steel needs more voltage than aluminum. The thicker the metal – the higher the setting. If you are dealing with rust, then you need to pump up the voltage in order to get through the rusty surfaces. If you are not sure what setting to use, go to step one. Most plasma cutters have a voltage to thickness chart in the manual. If you are planning to cut through very thick metals, you’ll need high voltage, so make sure that your outlet provides 220 volts.

Check the air supply and adjust the air flow and air pressure. You can find the air requirements in the owner’s manual. Don’t try to make any “average” settings. Each plasma cutter needs to be adjusted individually.


Check the Equipment

Even if you just purchased the plasma cutter, take 5 seconds to check if all is in order. Worn or incorrectly attached parts won’t just ruin your material, they can pose a danger to your health. Check the tip and the nozzle, as well as the electrodes. Worn electrodes can result in the arc blowing out of the side of the tip.

Pay attention to the power cord. Check if the power supply is sufficient for the work you are about to do. Some units are created to work with any power supply. Others need specific voltage.
Check the ground connection. Grounding is imperative to plasma cutters just as it is to the welding equipment.


Put the Safety Gear On

When using a plasma cutter, the safety can’t be over stressed. The protective outfit is similar to that of a welder. You need welding leathers, gloves, and goggles. Number 5 shade is the minimum requirement for eye protection when using the plasma cutter. But to be comfortable you should think about # 9 to 11. You might also want to consider getting a face shield or an auto darkening welding helmet. A helmet offers maximum protection while allowing you to see more clearly.

Don’t forget that plasma cutting is a rather loud process. If you are planning on a long cutting job, the attack on your ears will be uncomfortable. Consider earmuffs or earplugs.


Make a Sample Cut

Turn the machine on and make a sample cut. You should have a spare piece of metal you can practice on. A sample cut allows you to check your settings without ruining the metal you are planning to work on. If you’ve never used a cutter before, you should prepare a large piece to practice on. Stopping and continuing a long cut is never easy. Practice, practice, practice.

Go on to do your job. When you finish, turn the machine off, disconnect the ground clamp, and turn off the air supply.


Cutting Techniques

When learning how to use a plasma cutter, there are a few techniques you want to study.

Dragging

Dragging is the most common way to use the plasma torch. However, you can’t allow the tip to touch the metal, it will simply fuse. Depending on the type of your plasma cutter, you either keep the unit ¼ inch above the metal when cutting, which means you’ll lose some speed and precision. Or you can use drag cups. Drag cups are usually sold separately. Make sure to buy a couple since they are easily ruined. If you are not using a drag cup, operate the cutter at about 45-degree angle. This way the excess material will get blown away instead of coming at you. Meanwhile, you’ll be able to see the arc better.

Gouging

If you need to remove the old welds then you can use a gouging tip. The gouging tip creates a hole which is about 3 times wider than a regular tip makes. The plasma arc created by such tip removes more material. The arc generated by a gouging tip can be 1 – 1.5 inches long. Plasma cutter gouging produces less smoke and noise than the carbon arc gouging while offering more control over the arc. When you are gouging, you need to maintain a 40- to 45-degree angle to the base material. Deep gouging on one pass is not recommended. Make a few passes if required.

Piercing

Piercing is rather simple. All you have to is place the cutter at about a 40-degree angle to the metal. Activate the trigger. As soon as the unit generates an arc, bring the tip to a 90-degree angle.


Plasma Cutting Tips

1) When learning how to use a plasma cutter, you might want to take advantage of a few tips to make the process faster, easier, and more enjoyable

2) Match the tip to the amperage settings. Lower-amp tip has a smaller opening and maintains a narrower stream at a lower setting. A 40-amp tip used with an 80-amp setting will result in the opening distortion and reduce the life expectancy of the equipment

3) The faster the travel speed, the cleaner the cut will be. When you are dealing with a thicker metal, use the full output and vary the travel speed. When you are working with a thinner metal, reduce the amperage and use a lower-amp tip to sustain a narrow cut

4) The arc should exit the metal at a 15- to 20-degree angle opposite to the travel direction. If the arc is going straight down, you are working too slowly. If it sprays back, you are working too fast

5) When you are marking the metal for cuts, use a black marker or a piece of white chalk. These colors make it easier to distinguish the markings when cutting

6) If you are a beginner, always use a drag cup for the dragging technique

By following the above advice, you can learn how to use a plasma cutter in a matter of minutes. Don’t forget to read the manual and remember that the safety comes first. Good luck!


How to use a Plasma Cutter Video


You’re now well on your way to becoming a Plasma Cutting Guru. Click here to pick out a suitable machine that will get the job done. In our review process, we tried to make a selection that takes every different budget into account.

How Does A Plasma Cutter Work?

Most of the time we don’t think about how the construction tools work. They do their job and it seems more than enough. However, knowing the operation principle of various equipment can help you learn how to get the job done quicker and pay more attention to the safety.

Plasma cutters might seem like something from a sci-fi movie where futuristic tools are doing something close to magic. However, this equipment is actually rather old…some might even say, middle aged.


what does plasma cutter plasma look like

What is Plasma?

In order to get a better understand of how a plasma cutter works; let’s take a look at what plasma is.

There are four states of matte: solid, liquid, gas, and plasma. Plasma is the closest to gas than all other states. How do you change one state of the matter into the next? You heat it up. By heating up the solid matter, you turn it into liquid. Heating the liquid will turn it into gas. Heating up the gas will eventually turn it into plasma.

Plasma is a complicated state of matter. Heating forces the electrons to separate from the nucleus. Once they are released from the atom, electrons start moving very quickly. Since they are negatively charged, the electrons leave positively charged ions behind them. The collision of the fast electrons and ions leads to the release of great amounts of energy. This energy is what allows the plasma to cut through the metal.

Interesting note #1: Plasma is the most common state of matter in our universe.
Interesting note #2: The biggest piece of plasma we know is the sun.


How Does a Plasma Cutter Work?

Now that you know what plasma is, it’s easy to understand how plasma cutters work.

The goal of the plasma cutter is to turn gas into plasma in order to use it for cutting.

Plasma cutters send pressurized gas (it can be nitrogen, argon, oxygen, etc.) through a small channel. In the middle of the channel, there is a negatively charged electrode. Once the plasma cutter is plugged in, it sends the power to the electrode. Then the plasma cutter touches the metal and this connection results in a circuit. A spark is generated. Meanwhile, the gas passes through the channel and meets the spark, which heats it up until the gas turns into plasma. Voila!

How a Plasma Cutter works


Two Types Of Plasma Cutters

In the modern world, there are two types of plasma cutters. The choice of a plasma cutter depends on the volume of work that needs to be performed and the skills of an operator.

Manual Plasma Cutters

Manual plasma cutters are the most popular cutters for individual use. Hand-held plasma torches are portable, maneuverable and versatile. These cutters use shop air as a gas and can work with several incoming voltages. They are good for using on thin metal, so they are popular at metal service centers and can be used for construction work, vehicle repair, and artwork. Their main use is trimming the excess material from various metal parts.

When choosing a manual plasma cutter, you have to consider the thickness of the material you are planning to cut and the cutting speed you can handle. Fast cutting speed = low precision. Manual devices often can be configured to suit the operator’s skill level. However, most plasma cutters have a high learning curve. The risk of an electric shock when using a manual cutter is rather high. That’s why safety precautions are vital.

Automatic (CNC) Plasma Cutters

CNC (computer numerically controlled) plasma cutters are easier to use since the computer controls the way a head moves. This allows the cutter to make precise cuts and eliminates the human error during the cutting process. An automatic cutter increases the output and decreases the time required to get the job done. Automatic cutters are large machines that require a substantial amount of space. They are usually used in large service shops or factories.

While there is no need to teach operators to wield the cutter, you need to teach them how to work with the software. Most of the time, the learning curve of a CNC plasma cutter is much smaller than of a manual cutter. Automatic cutters are more expensive and require an extra power supply, which is not always available. Meanwhile, they offer you a chance to improve the cutting quality and quantity as well as the complexity of the work.

While there isn’t anything complicated about a plasma cutter, it’s still one of the most interesting tools developed in the 20th century. By taking what they nature gave us, we managed to create a powerful machine that didn’t just simplify the U.S. aircraft manufacturing business, it perfected the approach to construction all over the world.

You can check out both types in our full Plasma Cutter reviews page


A little history

The first plasma cutters appeared in the middle of the 20th century during World War II, when the U.S. engineers needed a more sophisticated way to join aircraft spare parts. They used inert gasses fed through an electric arc to completely replace the standard welding process.

After WWII was over scientists continued to research the innovative welding way and found out that they could improve the process. They restricted the inert gas flow opening to the nozzle, which altered the electric gas arc particles. This substantially boosted the speed and the temperature of the gas. It turned out that the plasma technology didn’t just help join the metal together, it could cut it up with ease.

Further research was done with the type of gas, gas flow rate, size of nozzle, voltage current and etc. Many tests were run to improve the plasma torch or plasma cutter of the 20th century. However, there were downsides of plasma cutting, such as loud noise, toxic gas, certain levels of UV radiation, and short nozzle life.

In the 1970’s European scientists came up with an underwater plasma cutting. This eliminated many side effects, such as toxic smoke, UV radiation, and noise, but significantly affected the precision since the operators couldn’t precisely see and control what they were doing.

In the 1980’s low amp plasma cutter appeared on the market. This breakthrough technology used pure oxygen as a plasma gas. After an underwater muffler and various oxygen injection technologies were developed, the popularity of underwater plasma cutting went through the roof.

In the 1990’s, plasma cutters faced a worthy competitor. When a laser appeared on the market, it immediately became extremely popular due to the precision it offered. Plasma cutter manufacturers quickly came up with a few innovations in order not to lose their position on the market.

Over the past 20 years many new technologies have been developed to maintain the popularity of a plasma cutte. Since these cutters are not as expensive as the lasers, they are still widely used. Computer-controlled cutters and portable devices became a choice of many companies and homeowners.


How does plasma cutter work video