What is laser cutting?

Lasers have been used in Industry for many years and are just becoming accessible to a wider audience and starting to be used in schools and colleges. We love the creative potential that a laser cutter brings.

The laser cuts or etches, with speed and precision, to the specifications of a CAD file. Images are sent to the laser cutter from a computer in much the same way as we send an image to a printer, but the material to be cut lies flat on the laser bed and the laser moves above it. This means the size of the laser bed is important and will determine the size of material you can work on. The two laser systems we utilise have bed sizes of 1225mm x 900mm and the other with a bed size of 900mm x 600mm meaning that the size of materials cut are constrained to that size in a single part.

The laser will cut or etch the image according to individual settings for the particular image and materials being worked with, so there is always a small amount of testing time required. Experience goes a long way with laser cutting as it can take a while to get to know the laser cutter / materials and understand how to get the best results from it.

Due to a laser cutters nature to reproduce consistent accuracy with speed time and time again, they are often used for batch production.

It is possible to input to the laser from any vector files, photographs and also hand drawings which can be converted using graphical design skills to cut or etch.

The science bit

One common misconception is that Lasers cut through the material by burning through it. What actually happens is that the laser emits photons which vaporise the material not cut.

When lasers cut something, they're only cutting in the sense that they're making atoms be not as attracted to one another as they once were. When you get down to the finer technical details, it is not really the same as mechanical cutting which we would associate with a saw or a pair of scissors.

Remember that lasers shoot photons, and when photons hit atoms, they excite electrons. If you excite these electrons enough, they'll have enough energy to disassociate from the atoms they previously "belonged" to. This makes individual atoms disassociate with whatever other atoms they were once bonded to, and in the mad scramble to go to a lower energy state, they very likely do not go into the same configuration they were before. Some atoms, like the ones directly hit by the laser beam, go to a vapour and float away. Others "choose" one side of the material to go to. Any bonds which the material originally had with itself are then dissolved, so it is effectively cut.

This is different to using saws, knifes or scissors to cut the material. The methods of these things cutting are purely mechanical, and you don't have to worry about smell and sometimes dangerous vapours and particulates as much as when cutting with a laser.