Laser Cutting Equipment FAQ’s

Here are some answers to Frequently Asked Questions about laser cutting.
Q: What is laser cutting and how does it work?

A: Laser cutting systems use high-powered lasers to vaporize materials in their beam path. Because cut away areas are vaporized the hand labor or complicated extraction methods otherwise needed for small part scrap removal is eliminated. In screen printing applications the types of lasers that are commonly used are CO2 lasers. The powering on and off of the laser beam and the way in which the beam path is directed towards the substrate effects the specific cuts that the artwork requires.

There are two basic designs for laser cutting systems— gantry systems and galvo (galvanometer) systems. Gantry systems are very much like the XY plotters that many screen printers use for prototyping work. These gantry systems physically direct the laser beam around perpendicular to the material being cut. Gantry systems are inherently slow, just like other XY plotters, but are a good fit for some very wide format jobs that require laser cutting.

Galvo systems are generally a much better option for screen printing applications. Galvo systems make minute adjustments in mirror angles to reposition the laser beam in different directions, as the artwork requires. Unlike gantry systems, galvo systems are relatively quick (i.e. as fast as 100 fpm for simple straight cuts in many substrates) and are used beyond prototyping for full production work.

Q: Why is laser cutting called digital die cutting?

A: Laser cutting systems are tool-free. They take any vector-based digital image and import it into their operating software to set up a job. The best-in-class laser cutting systems can complete set up from these imported digital images in just a few minutes.

The ‘digital die cutter’ term that is used interchangeably with laser cutting speaks to this advantage that tool-free cutting systems provide, especially when used in combination with digital printers. The combination of an imported digital image into a digital printing press followed by a laser cutting system allows one to move from artwork to finished product in just a few hours, or even less for very short runs.

Q: Why should we switch from a tool-based cutting system to a tool-free (laser cutting) system?

A: It’s not a matter of switching to tool-free cutting. Rather, it’s advisable to add laser cutting to whatever tool-based cutting systems you already utilize in your finishing department.

Whether one is screen printing flexible circuits, or complex product faceplates such as those used on mini cell phones, or creating an intricate design label, there will come a point when you run up against the very real limitations of any die-based cutting system—whether it is a rotary die cutter, platen press, optically-registered gap press, etc. Sometimes this limitation presents itself when handling ultra-thin delicate substrates where there is a difficulty making precise cuts with a mechanical die. Even with more substantial materials tiny features such as micro-perforations and especially design features including many small sharp angles pose challenges to a tool-based cutting system. Male-female dies face inherent constraints in creating corners that are less than 30 degrees, even in best-in-class tool-based cutting systems. Then there are the problems of adhesives that quite literally gum up the works of tool-based cutting systems. Or, consider the costly wear and tear on dies that make it nearly impossible to cost-effectively cut abrasive substrates.

Laser cutting systems, because they are tool-free, do not have to contend with any of these challenges. Better yet, the costs and delays involved in tool fabrication are bypassed. For short runs especially the costs and time delays for tooling are especially significant. That is why laser cutting systems offer such a clear advantage for prototyping.

However, it would be a mistake to think that laser cutting will replace the tool-based cutting technology used by screen printers. If part geometries are not out-of-reach of a tool-based cutting system, and if easier to cut substrates are being cut, if hand labor would not be required for parts extraction, and especially if it involves a long run length, a male-female die or steel rule die based cutting system will many times provide a more cost-effective solution.

Q: How are today’s laser cutting systems different from earlier generation technology?

A: The capabilities of latest generation best-in-class laser cutting systems are dramatically more advanced than the technology that was first introduced five or so years ago. Basically, three areas of technological improvements contribute to these more far ranging capabilities – advances in lasers, software, and software integration.

Manufacturers of the lasers used in laser cutting technology have continued to improve them and to offer better lasers at lower cost. These newer lasers shape beams with greater precision. And, higher powered lasers now cost less, such that even basic laser cutting systems can use competitively priced 200 watt or 400 watt lasers today, compared to these only being available in the priciest systems several years ago. To a certain extent, higher-powered lasers facilitate faster cutting action. The better-shaped beams of today’s lasers are also more easily steered by galvo systems at greater speeds.

These improvements in lasers, while significant, are surpassed by the advantages conferred by the high quality software engineering in today’s better laser cutting systems. The best-in-class systems have improved software at every level— the building block algorithms of programs are more robust, the mathematical concepts that underlie the programming are more sophisticated, and the overall systems integration is more comprehensive. The end result is in software that works behind the scenes, so to speak, to control and maneuver laser beams within tolerances that were out of reach only a few years ago and to do so without any programming expertise required of the operator.

Users of newer best-in-class laser systems see these improvements in several ways. The telltale pinholes and burnthroughs that were made by earlier generation laser cutting systems have been eliminated. In turn this has made a wide array of special features that laser cutters can excel in— perforations, creases, score lines, kiss cuts, consecutive numbering, personalizations, etc.—all the more doable.

Q: Are laser cutting systems used for prototyping or full production?

A: Both. The advantages of laser cutting systems being tool-free will always make them a superior option for prototyping work because there is no delay or expense for tooling. Now, however, better lasers and better software engineering create a speed improvement in the newer laser cutting technology. The better shaped beams not only make steering the lasers faster but the best-in-class laser cutting systems take this a step further with software engineering that shaves milliseconds off of every operation cumulating in speed increases. These systems’ software takes it even further by optimizing cutting sequences for faster throughput. They also use smart control systems that monitor operating conditions such as registration, web control, and integrated laminating and slitting operations and allow programming of automatic shut-off at the completion of runs or when material or machine conditions require. The upshot is that today’s laser cutting technology is geared for full production too.

(Note: The speed of laser cutting systems is highly job dependent. A highly intricate cutting pattern involving a long linear cutting path will take longer than a straight crease line, for example.)

Q: What is involved in job setup and job changeover?

A: Setup is comparable to that required for a digital printing press. In the better laser cutting systems, software tools are built in to improve imported DXF or DWG files for best laser cutting results. These tools provide corrections for difficulties created by vector type files allowing shorter setup times and overall improvement of the laser cutting results. The best-in-class systems also will simulate the job production rate during set up telling operators precisely how long a job will take. And, the job set up specifications are saved so that they can be recalled at a later time, making a changeover to that repeat job a simple matter of a few keystrokes done in seconds.

Q: What level of operator training is required?

A: In the newer and better laser cutting systems, the skill levels of machine operators that are required is very similar to those that are needed to operate a cable television menu screen. Spartanics Finecut Laser Cutting System, for example, has an interactive help tools (Video Wizard) that makes it possible for workers who have never used a PC to fully operate the Finecut Laser Cutting System and all its features. This interactive Video Wizard also helps to bypass language barriers because lessons are taught by example rather than spoken or read.

Q: What are the limitations of laser cutting systems?

A: Laser cutting systems can make cuts as small as the laser beam diameter, i.e. 210 microns in the better systems. Material limitations are sometimes an issue. Although the precise definition of “thick” is changing and dependent on material grade, laser cutting on thick polycarbonate substrates continues to be beyond the current systems’ capabilities such that discolorations usually occur. If polycarbonates are too thick for laser cutting, the best technology fit is usually with the high precision optically-registered steel rule die or hard tool cutting systems that can deliver registration accuracy +/-0.1 mm.

For especially long runs with many hundreds of thousands of linear feet the expenses for tooling are insignificant contributors to overall job cost and the delays for making tooling are insignificant, tool-based cutting systems (rotary die cutters, optically registered gap presses, platen presses) will continue to be the cutting method of choice. For such large orders, if dies can be fashioned to reliably handle the required details of part geometries, there is usually little advantage to laser cutting systems because even the highest wattage modern systems are still a bit slower.

Q: What does a laser cutting system cost?

A: A high-end fully featured laser cutting system costs US$250,000+, comparable to the cost of a high precision optically registered gap press. There are no additional costs for tooling however, which makes laser cutting systems comparably lower-priced over its lifetime.

Q: How do the various brands and models of laser cutting systems one finds in the marketplace differ and what are the suggested practices to find best fit technology?

A: Buyers Beware!—there is a wide range of capabilities in the laser cutting systems one runs into, largely determined by the sophistication of the software engineering employed. This means that you need to test various options thoroughly before you purchase a system.

One way to do that is by providing materials to get samples cut to your specifications and to look at the range of samples provided by manufacturers and the cutting precision they demonstrate. Better yet, it is highly recommended to enlist the contract manufacturing services that are provided by reputable laser cutting system manufacturers. These will not only demonstrate ability to generate the features your applications require but will give you details on expected operating efficiencies and throughput for your applications.