An air compressor is a device that – as the name suggests- is used to compress and pressurize air inhaled from the atmosphere and convert power into potential energy in the process. Air compressor technology has found its way into a wide variety of applications in our everyday lives. In fact, it won’t be an exaggeration to say that for a lot of us, It has even become a part of our daily lives. Air tools have started being widely used, and to run these pneumatic machines, we need compressors.

Air compressors have nowadays become an essential component of the working system, be it in a home garage or any factory environment. Whether you are a DIY enthusiast or a professional mechanic, there is a significant possibility that you will be using an air compressor to operate different air tools.

One such task is plasma cutting. Construction works, welding, auto mechanics, and many general household works that involve cutting of metals will involve plasma cutting. Plasma cutters need compressed air to operate.

Do all plasma cutters require an air compressor?

There are a few plasma cutter models that come with an inbuilt air compressor. These plasma cutter models provide you with portability and ease of use. But there’s a downside. These plasma cutters are able to cut only thin metals; they are not designed for heavy-duty operations.

In most cases, you’ll be required to connect the plasma cutter to an external air compressor for this purpose. So, before buying a separate air compressor for this purpose, you need to figure out how much air supply or air pressure you’ll need and purchase a unit accordingly. You can handle small cuts with any type of compressor, but if you want to work uninterrupted on your long cuts and do not want to compromise on the quality of works, you should decide carefully which compressor to buy for your workspace.

How much air does a plasma cutter require?

The airflow and air pressure requirements may vary depending on the models of your plasma cutter. But, if you want to work with a plasma cutter, the bigger you can go for, the better. So, what you can do is check the requirement of your plasma cutter and buy a compressing machine with a higher CFM rating than that. You should go for a device that has a 1.5 to 2 times higher CFM rating than what your plasma cutter requires. This will ensure that your machine keeps running when the air compressing unit takes time to refill.

For example, let’s assume that you’re using the Hypertherm Powermax30 XP. This particular unit requires 4 CFM at 80 PSI. So, you would want a compressing machine that has a rating of around 6-8 CFM to uninterruptedly operate your device and reduce the chances of facing any supply issue.

Your power supply depends on the amount and the level of works that you do. So, in the case of plasma cutting, how much cutting you’ll do will decide the air consumption and air pressure required from your compression unit.

For example, if you are using a small plasma cutter, you’ll most probably have air supply requirements of about 4-5 standard cubic feet per minute at 90 PSI. A 3/8-inch steel plate can be cut up using this kind of system. On the other hand, to cut a width of 3/8″-3/4″ plate, you’ll require a medium-sized unit that can supply about 6 SCFM at 90 PSI. But, if you need to cut up a steel plate with 3/4″-1½” width, you’ll need heavy-duty units that are capable of supplying about 7-9 CFM at 90 PSI.

You can do most of the DIY projects or home-based projects by getting a compression unit that has a CFM rating slightly higher than the plasma cutter. An air compression unit with a 20-gallon compressor tank will be sufficient for you if you’ll not be using the plasma cutter for an extended period of time.

However, it won’t be enough to fulfill the air requirements of making longer cuts. To maintain the air requirements of such large-scale operations, you’ll have to use an air compression unit that has a larger compressor tank, such as an air compressor with a 60-gallon, which should be capable of providing 1.5-2 times greater supply than the plasma system requirements.

What air pressure is required for plasma cutting?

Plasma cutters operate at a wide range of different PSI settings depending on their types and models. So, you will have to decide which unit and what PSI you require according to your plasma system requirement. You can find the information about the correct settings of your plasma systems in your plasma manufacturers manual that comes with your tool. It is evident that the larger tools will require a higher level of PSI, and the smaller tools will require a lower level PSI.

For instance, a Hypertherm Powermax30 XP 30 amp plasma cutter runs at 80 PSI and uses 4 SCFM (standard cubic feet per minute). On the other hand, a Hypertherm Powermax45 XP 45 amp plasma cutter runs at 90 PSI and uses 6.7 standard cubic feet of air per minute.

Does the quality of the compressed air affect cut quality?

The quality of compressed air used is a vital factor for plasma cutting. The presence of moisture or oil in compressed air can have an adverse effect on the cut quality. If you use unfiltered air, it will deteriorate the consumables (nozzle, electrode, shield, and retaining cap) quite fast, and your equipment won’t last much longer, increasing the additional cost of replacement.

So, you must make sure that the compressed air use is dry and as clean as possible. You should drain your compression unit as often as possible, use an air dryer, and also add an external filtration system (between your plasma cutter and air compressor) to help prevent the contaminants from sabotaging the operation. You should also ensure the maintenance of these additional accessories after regular intervals.

Keep in Mind

  • The CFM of air compressing units are typically rated at 90 PSI and the maximum PSI possible for the unit. Multiple brands maintain this standard.
  • Manufacturers, in most cases, present an increased (kind of best case scenario) CFM rating. So, if the machine you’re researching says that it is capable of producing 5 CFM, then you’ll most probably have 4 CFM during practical operations.

Final Words

Deciding for an appropriate air compression device for your plasma cutter is a crucial task. It will have a severe impact on the efficiency and quality of your work. If you buy a compressor that is too small for your need, then the air supply will be inadequate that will interrupt the work. Thus, it will waste time, and you’ll lose efficiency. Buying a larger compressor may be safe, but it’ll be a waste of money if you buy a too large machine and there’s no possibility of using that much power. Also, the quality of the compressed air has an impact on the quality of the cuts you make. If the quality is poor, it will have an adverse effect on your work and may even damage your equipment.

So, you should consider your usage plan and the air requirements according to the projects you are planning to do before deciding on a specific model.

We hope that this article has been of help to you in deciding on an appropriate air compressor setup for your plasma cutter. If you have any further queries, do not hesitate to contact us.

Good luck!

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Hi, and welcome to Toolented. My name is Michael D. Sanders. I am a Mechanical Engineer by degree, who is a blogger by passion, and this combination of knowledge and passion is what brought Toolented to life. On my blog website, you will find necessary information about your needed automotive tools, reviews of your potential choices, and comparisons between different types of tools. To learn more click here.

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