Laser and Plasma Cutting
Interested in sheet material fabrication? Modern tools and methods make this easier than ever before
Cutting sheet materials to precise specifications can be tedious and time consuming when done by hand. Depending on how tight the specifications are, they may be borderline impossible to achieve without the aid of a computer-controlled machine.
Luckily, there are solutions available for these tasks. Let’s go through two of them: Plasma cutting and laser cutting.
Plasma Cutting
Plasma cutting is the process of cutting a material by heating it up to melting point and blowing the molten material away, leaving a gap in its place.
The interesting part is in how it achieves this heating. A compressed gas is forced through a nozzle, which is directed at the material to be cut. A high voltage is applied across an electrode near the nozzle, through the compressed gas, to the nozzle itself. This high potential causes the gas to ionize into a plasma. The plasma is then forced downwards to the material, which creates a conductive link between the electrode and the material. With current now able to flow into the material, it heats up intensely and becomes molten.
Plasma cutting works with any electrically conductive material, such as steel or aluminium, and can cut through sheets many millimetres thick.
While handheld plasma cutters exist, at CALT Dynamics, we use a large, computer-controlled plasma cutter, which reduces human error and increases precision and repeatability.
Laser Cutting
Laser cutting is the process of cutting a material by directing a high-power laser beam that vaporises the material and blows it away with compressed gas.
Laser cutting is another process by which materials can be cut. Here, a high-power laser (usually pulsed) is directed by mirrors into a cutting head, which houses a lens that focuses the laser beam onto the material to be cut. As the concentrated beam strikes the material, it vaporises and is blown away by compressed gas supplied to the head. The head is moved around in a specified pattern to produce the desired piece.
While laser cutting may be applied to many materials, including metals, at CALT Dynamics, our laser is more suited to cutting materials such as wood and plastics.
Laser Etching
While lasers can be used to cut clean through materials, by adjusting the power it can be used to etch into the material without cutting through.