Why is the laser causing excessive charring, smoke, or repeated flame?

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Heavy smoke, charring or repeated flame usually traces to a short list of causes: an unwatched run, incorrect power settings, insufficient exhaust…

Heavy smoke, charring or repeated flame usually traces to a short list of causes: an unwatched run, incorrect power settings, insufficient exhaust, unsuitable material, dirty optics, or a machine that is not cleaned out regularly. Whatever the cause, any flame means stop: use the emergency stop or the switch you were trained to use, not just the software job. Do not keep adjusting settings to make it stop. Six usual causes of heavy smoke, charring or repeated flame, and the rule for any flame A fishbone diagram. Six bones lead to a head box that reads heavy smoke, charring, or repeated flame. Top bones: an unwatched run, incorrect power settings, insufficient exhaust. Bottom bones: unsuitable material, dirty optics, and a machine not cleaned out regularly. A red strip underneath says any flame means stop with the emergency stop or the switch you were trained to use, do not open the lid, move students away, and follow your school’s written fire procedure. Unwatched run Incorrect power settings Insufficient exhaust Unsuitable material Dirty optics Not cleaned out regularly Heavy smoke, charring, or repeated flame Any flame means stop: emergency stop or the switch you were trained to use Do not open the lid to look. Move students away. Follow the written fire procedure. Do not keep adjusting settings to make it stop. These six are the usual causes, and more than one can be in play at once. An authorized person stays with the machine for the whole run, able to see the job and stop it. Never cut material of unknown composition. For a flame, do not open the lid to look. Move students away, then follow your school’s written fire and evacuation procedure. MIT directs shutting off the cutter, air assist and filtration on a detected flare-up; your school’s written fire procedure may specify a different shutdown sequence. If the building alarm sounds, evacuate and never return to the machine. This page assumes an enclosed machine at Class 1 or Class 2 in the configuration you run. Open-frame, open-bed, pass-through or converted machines, machines at Class 3B or 4 in normal use, and machines of unknown class are not covered; with no lid to contain a flame, they need a laser safety officer and a written program first. MIT gives that same short list of fire contributors, and notes that even a properly maintained and exhausted machine can flare up, and an unobserved flare-up can grow. That is why an authorized person must stay with the machine, able to see the job and stop it, for the whole run. Never cut material of unknown composition. After any flame, do not run that job again until the material, file and setup are reviewed; anything involving the machine itself goes to the person responsible for the equipment. Whether the lid stays closed or opens during a fire inside the machine is for your school’s written procedure. Extinguisher type, placement, and whether the room has one are set by your institution’s fire safety plan and fire authority, not by this page or the instructor.

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