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Laser Cutters need two additional devices which move atmosphere: blower which removes air / extracts smoke from machine and air flow compressor as a source for compressed atmosphere for so called air flow assist.
Laser cuts by heat, very high warmth focused in tight beam. Side items of high temperature are smoke and fire, both are not welcomed addition, smoke disperses laser reducint it's efficienty and fire causes charring of materials / edges and may even escape control causing serious emergency.
Fire needs surroundings to burn but it will certainly also die if you blow too hard, think of a candle in the wind. This is essentialy what atmosphere Laser Cutting Air Compressor assist is usually for: compressed atmosphere is extruded directly at the laser mind in a very restricted stream and is fond of where laser touches material.
Pressure of air is key variable for air help efficienty, inside our shop we discovered that optimal value is between 2 and 3.5 bar (31-50psi).
To achieve required pressure compressor must push certain level of air through air flow assist opening, precise volume depends upon size of the opening and desired pressure. Top quality laser cutter heads have small and finely tuned openings while cheaper chinese cutters just blow in general direction via large holes.