There are many different tooling processes that digital manufacturing utilizes. However, every digital manufacturing process involves the use of computerized numerical controlled machines (
CNC). This technology is crucial in digital manufacturing as it not only enables mass production and flexibility, but it also provides a link between a CAD model and production. The two primary categories of CNC tooling are additive and subtractive. Major strides in additive manufacturing have come about recently and are at the forefront of digital manufacturing. These processes allow machines to address every element of a part no matter the complexity of its shape. • Ink-Jet Processing
- Although the most widely used ink-jet process is used for printing on paper, there are many that are applied in engineering. This process involves a printhead depositing layers of liquid material onto a filler powder in the shape of the desired object. After the powder is saturated, a fresh new layer of powder is added continually until the object is built. Another less known material drop deposition process use a build and support material to produce a 3D model. The build material is Thermoplastic and the support material is wax. The wax is melted away after the layered model is printed. Another similar technique uses (DBM) Droplet based manufacturing to build Thermoplastic models without support with 5 axis drop positioning • Laser
sintering and fusion
- This process utilizes heat produced by infrared lasers to bond a powdered material together to form a solid shape. •
Solid ground curing - A layer of liquid photopolymer is spread over a platform. An optical mask is generated and laid over the polymer. A UV lamp cures the resin that is not blocked by the mask. Any remaining liquid is removed and the voids are filled with wax. Liquid resin is spread over the layer that was just produced and the process is repeated. When the part is finished, the wax can be melted out of the voids. •
Laminated-Object Manufacturing - A sheet material is laid on a platform and a laser cuts the desired contour. The platform is lowered by one sheet thickness and a new sheet is laid with a layer of thermal adhesive between the two sheets. A heated roller presses the sheets together and activates the adhesive. The laser cuts the contours of this layer and the process is repeated. When the part is finished, the leftover sheet material around the perimeter of the part must be removed. The final part is coated with sealant. •
Fused filament fabrication- FFF is the most commonly used form of 3-D printing. Thermoplastic material is heated just beyond solidification and extruded onto a platform in the desired shape. The platform is lowered, and the next layer is extruded onto the previous layer. The process is repeated until the part is complete.
Examples of subtractive tooling and processes •
Water Jet Cutting - A water jet cutter is a CNC tool that uses a high pressure stream of water, often mixed with an abrasive material, to cut shapes or patterns out of many types of materials. •
Milling - A CNC mill uses a rotational cutting tool to remove material from a piece of stock. Milling can be performed on most metals, many plastics, and all types of wood. •
Lathe - A CNC lathe removes material by rotating the work-piece while a stationary cutting tool is brought into contact with the material. •
Laser cutting - A Laser cutter is a CNC tool that uses a focused laser beam to cut and engrave sheet material. Cutting can be done on plastics, woods and on higher power machines, metal. Recently, affordable laser cutters have become popular with hobbyists. == Benefits ==