The size of the correct air compressor and the amount of air pressure it can produce will depend on your plasma cutter’s size and exactly what applications you have in mind.
Each manufacturer of plasma will indicate the minimum airflow and minimum air pressure for their plasma cutter in the accompanying owner’s manual. Requirements will differ between brands and models
What size air compressor is appropriate for use with a plasma cutter? A basic middle-range plasma cutter may need about four to eight cubic feet per minute propelled at 90 to 120 PSI (pounds per square inch). However, note that each unit will have its own specific requirements. And the size of the air compressor must be correlated directly to the thickness of the metal that you want to cut.
Do Plasma Cutters Need Air Compressors?
Yes, plasma cutters do need air compressors unless you have a plasma cutter with an air compressor directly built into the cutter unit. Any plasma cutter will necessitate an adequate force of air pressure to function properly.
Therefore, it will require an air compressor whether it is external or internal to the plasma cutter unit.
Do All Plasma Cutters Need Air Compressors?
No. The only plasma cutters that do not require an external air compressor are those cutters that feature built-in air compressors.
Plasma Cutter Air Requirements
An important aspect to think about when considering airflow and pressure requirements for your plasma cutter is that the manufacturer will indicate the minimum requirements.
This means that if you only use your plasma cutter occasionally for DIY metal cutting projects or for cutting a piece of metal here and there, you can choose an air compressor that meets these requirements just above the minimum necessities indicated.
If, on the other hand, you cut metals regularly or you plan on cutting metals of a substantial thickness, you should choose an air compressor with a capacity that is at least one-and-a-half times more, if not twice as much as the minimums that are manufacturer-recommended.
Although airflow and pressure requirements are fundamental to quality performance from your plasma cutter, they are not the only things that figure into the equation.
The air that eventually enters your plasma cutter must be of the highest quality. Without consideration for the air quality, consumables will have shorter lifespans, and cutter results will be less than satisfactory.
An air compressor alone cannot guarantee the quality of the air used. It is equally crucial to concentrate on what happens to the air upon leaving the compressor.
This is a crucial consideration because as the air leaves the compressor, it can absorb moisture or condensation in the airline. Or if you power more tools than just your plasma cutter alone with the air hose, there may be contaminants in the airline. This all equates to air, that once it reaches your plasma cutter, may no longer be either dry or clean. A solution to this is to double filter your air before it gets to the plasma cutter.
Filter it once at the compressor and a second time at the inlet for gas. This may be a bit more expensive but can protect your power supply, your torch, and your consumables, meaning you’ll be saving money long term. And most importantly, with top-notch air quality, you’ll achieve better quality cuts as well.
After consulting the minimum airflow and minimum air pressure requirements indicated by the plasma cutter manufacturer, select an air compressor that offers flow and pressure above those minimums. And if you cut a great deal, or cut particularly thick metals, choose an air compressor that offers flow and pressure 1.5 to 2 times greater than the minimums indicated.