General Requirements
The quality of a laser machine can be seen in your results, and is affected by factors such as aesthetics, accuracy, repeatability, and adherence to specified standards or expectations. One quick way to check quality: laser engrave text using small fonts (3 point) on anodized aluminum at the laser machine's maximum stated speeds. The resulting text should be sharp and consistent throughout the entire field of the laser machine, and repeatable from part to part. Thorough examination of the results will provide you with a clear indication about the quality of a laser machine. Speed is a factor - Trotec's Speedy II, for instance, reaches up to 140 inches/second (355 cm/second) - the highest speed available in the industry - while still delivering top-quality results.
The laser source is another critical factor in ensuring total quality. Over time, inexpensive laser sources show considerable variations in laser power, resulting in a deterioration of the laser machine's performance. Another essential point is the laser beam quality. An optimum laser beam should be as parallel as possible, and should provide for a stable and symmetrical distribution of the laser energy. Some lasers have an elliptical distribution of laser energy rather than a round one, which can adversely affect the laser performance - especially when in vector mode. The laser source should also include a fast rate of pulsability. The faster a laser source can be switched on and off, the more accurately individual points can be produced and positioned. If the edges of a laser engraving output are frayed, this could indicate both inaccurate mechanics and/or poor pulsability of the laser source.
Check to make sure that your laser vendor meets your expectations for quality results. Ask for a demonstration of maximum engraving speeds using the smallest text possible. Closely review the edge finish on cutting jobs. Make sure the results are repeatable without recalibration or exhaustive set ups. Find out what mechanical components are being used in the motion system, making sure that they are the best available both for high performance, and long equipment life. Make sure any belts or cables used do not stretch (needing frequent adjustments) or have a tendency to break under heavy stress. Finally, check to see if precautions have been taken to protect vital components from dust, dirt, and debris, which are often unavoidable when it comes to laser processing.
The Trotec Promise
Trotec laser machines incorporate only the best components in their design to ensure top results. High levels of accuracy and repeatability are achieved through the use of the encoders in brushless servomotors to provide exacting positioning information, unlike stepper motor components often seen in laser machines of a lower quality.
The quality of your laser system is also critical in ensuring a long lifespan and high return on investment. Motion system components should be protected for reliable and longest lasting results. At Trotec, we use the InPack Technologyä to ensure that our motion systems are protected against environmental contaminants, like dust. We use high performance industrialized linear movers and steel toothed cables. Other cables, such as Kevlar, stretch over time and need to be monitored and replaced frequently, while glass fiber cables often break during heavy-duty cycles.