Volumes of production

Suited to batch production.

Unit price vs. capital investment

Low capital investment as there is no tooling because the cuts are determined by a CAD file.

Speed

As with all methods of cutting, the speed of this process is dependent on the type of material used and its thickness. As a rough estimate, titanium alloys between 1/50 and 3/8 inch thick can be cut at a rate of 8 to 40 feet per minute.

Surface

The process will leave burn marks on wood, but on metal can give a clean edge with no need for post finishing. However, metal surfaces should be left unpolished before cutting, as highly polished surfaces act as reflectors and decrease the effectiveness of the process.

Types/complexity of shape

Depending on the machinery, the laser can be mounted horizontally or on a multi-axis head, allowing for highly complex shapes to be cut in three dimensions, a method that is sometimes called laser-beam machining.

Scale

Limited to standard sheet sizes.

Tolerances

Tolerances are extremely high, with holes of as little as 1/1000 inch in diameter being possible.

Relevant materials

Often used on hard steels such as stainless and carbon steel. Copper, aluminum, gold, and silver are more difficult due to their ability to conduct the heat. Nonmetallics can also be laser cut, including woods, paper, plastics, and ceramics. Materials such as glass and ceramics are especially suited to laser cutting, since it would be difficult to cut the materials in intricate patterns using any other techniques.

Typical products

Model components, surgical instruments, wooden toys, metal meshes and filters. Laser-cut ceramics can be used as industrial insulators and furniture can be produced using laser-cut glass or metal.

Similar methods

Water-jet cutting (p.42), die cutting (p.40), electron-beam machining (EBM) (p.24), and plasma-arc cutting (p.33).

Sustainability issues

Laser cutting is very energy intensive in order to sustain the beam intensity, and the speed is considerably slower when working with thick or large pieces. However, as no contact is made between the tool and the substrate, maintenance is low and this reduces material consumption through replacement parts. As with all sheet cutting techniques, material wastage is often high. The nature of the material determines whether waste can be reheated and recycled.

Further information

www.miwl.org.uk

www.ailu.org.uk

www.precisionmicro.com

Oxyacetylene Cutting

AKA Oxygen Cutting, Gas Welding, or Gas Cutting

This is a process for cutting metal plate in which oxygen and acetylene are combined at the end of a nozzle and ignited, producing a high-temperature flame. The metal is preheated with this mixture of gases, and then a stream of high-purity oxygen is injected into the center of the flame, which rapidly oxidizes the work piece. Because thermal cutting methods are based on a chemical reaction between the oxygen and iron (or titanium), thin or narrow materials are not suited to the process because the heat can cause them to distort.

This sort of cutting can be undertaken either manually or as an automated process. In the manual operation, the familiar worker in coveralls, with full-face protection, provides the traditional image that sums up this process. In this scenario, the worker may often be welding, rather than cutting, materials.

–  Suited to thick metal plate.

–  Adaptable to hand or automated use.

–  Restricted to a narrow range of materials.