All Laser Cutters need two additional gadgets which move air flow: blower which removes atmosphere / extracts smoke from machine and atmosphere compressor as a source for compressed atmosphere for so called atmosphere assist.
Why and How
Laser cuts by heat, very high temperature focused in tight beam. Side products of high heat are smoke and fire, both are not welcomed addition, smoke disperses laser reducint it’s efficienty and fire causes charring of material / edges and will even get out of control leading to serious emergency.
Fire needs atmosphere to burn nonetheless it can also die if you blow too hard, think of a candle in the wind. This is essentialy what atmosphere assist is for: compressed air is extruded directly at the laser mind in a very tight stream and is directed at the place where laser touches material.
Pressure and level of air
Pressure of atmosphere is key variable for air assist efficienty, in our shop we found out that optimal value is between 2 and 3.5 bar (31-50psi).
To attain required pressure compressor must push certain volume of air through air assist opening, specific volume depends upon size of the opening and https://www.ever-power.net/?s=laser+cutting+air+compressor&post_type=product desired pressure. High quality laser beam cutter 
heads have small and finely tuned openings while cheaper chinese cutters simply blow generally direction via huge holes.
Proper compressor
When choosing compressor you have to consider if it will be able to constantly provide desired pressure and volume of air. Little airbrush compressors small compressors boast impressive pressure figures but actually poor flow rates sufficient only for airbrush pistols. Even if small compressor would be able to push enough air it’ll likely overheat in short while.