Even though lasers are around for a while now the array of applications and new ideas invented with and around laser systems seem to be an endless string of creativity matched with (of course) commercial interests. However, at the end of the day there is only a limited type of materials that can be processed. So, approach the typical laser applications is easier from the material side of things. The following paragraphs are meant to give a basic overview over just a few typical and some maybe some not so obvious materials that are laser processed to add value to the final product. Excluded for the purpose of this article are processes such as metal cutting and welding that require higher powered lasers.
Timber – Processing options: engraving, cutting. laser type: CO2 laser.
Timbers of all sorts are perfectly suited for laser processing. They engrave nicely and can usually be cut pretty easily. However, very often cutting leaves some sort of blackened finished. So, usually the product is either sanded or otherwise cleaned up after the cut depending on the purpose of the item. MDF and most types of plywood are also suitable. Plywood is worth testing up-front, though, since the used glue used can have a significant impact on the quality of the cut as well as lifetime of the filter system.
Plastics – Processing options: engraving, cutting, colour changing. laser types: CO2, YAG/Fibre Lasers
Acrylics and ABS plastics seem to be amongst the most popular plastics for CO2 laser processing. However, Acetal (mostly medical industry), Linoleum, most rubbers, Polyester, Polystyrene and certain Polyethylene and Polypropylene mixtures work quite well too. At the end of the day, Polycarbonates tend to discolour and regular Vinyl usually leaves yellowish edges, though there are laserable versions available that do the job. Stay away from PVC. Lasering it releases hydrochloric acids that are harmful for people and destroy the machinery. In general, when working with different sorts of plastics it is almost always worth giving it a go and get samples done to see the actual outcome. This is especially true when a colour change process with a YAG or fibre laser is needed. Also, since the smoke of many plastics is highly flammable it is worth talking to the chosen laser suppliers about what their systems offer to reduce the risk (gas kits, temperature sensors, filter systems, etc).
Paper and Cardboard – Processing options: engraving, cutting; Laser type: CO2
Besides being used for the obvious engraving and cutting in the promotional and other industries lasers are quite commonly used for kiss-cutting of paper, plastic or even foam based labels, shapes, etc. - kiss-cutting being the process of cutting without touching the underlying liner. This is a clean and flexible procedure that can also be fully integrated in an automated production line if necessary.
Textiles – Processing options: cutting, some engraving: Laser type: CO2
Even though most of the lasers are used for cutting industrial textiles there are some creative minds out there that engrave blue jeans or cut shapes into kitchen towels. The shoe industry uses lasers for engraving and cutting leather.
Bare metals – Processing options: engraving, colour changing; Laser type: Fibre laser (YAG)
The main benefit of laser processing bare metal compared to let’s say mechanical engraving is that it is much less labour intensive, easier and way more flexible. A fibre laser (YAG) marks the metal directly without any pre or post processing. It is even possible to laser the metal without ablating any material, however, leaving a nice and dark mark. As a result, fibre lasers more and more replace or complement existing engraving, paint filling and printing processes. Since not all metals react exactly the same way to lasering it is again wise to get some samples done up-front.
How to go about finding the right laser solution
Due to the variety of options that are out there in the market it is worth having a close look at the very differences between the solutions. Engineering and design of the equipment are just as important as ease of use and the level of service that can be expected after the purchase. A comprehensive approach might also include comparing samples. However, to be perfectly honest, standard, exhibition-like samples are almost interchangeable between suppliers, since they are mostly created in perfect conditions. To get a real comparison it is probably worth the trouble sending your specific material and file to all suppliers in question. Response time and quality of the product are usually good indicators, not only for the quality of the equipment but for the kind of service level you can expect after the purchase.