For Sydney-based T R Savage & Sons for instance, DDM offers an alternative to conventional metal-cutting manufacturing methods such as milling or turning with considerable time savings.
Savage Design Director Joel Savage explains that there are virtually no delays in moving from a robust digital design to the manufacturing process with the direct, uninterrupted progression from concept to part reducing the manufacturing time to as little as one day.
The general concept of additive manufacturing remains the same since its introduction 20 years ago, though its intended use has progressed from simply prototyping to production.
Direct digital manufacturing uses CAD, 3D scan data, DICOM data or any other to drive an additive manufacturing machine that makes usable parts such as components that go into sellable products, pieces of production machinery, replacement parts, or manufacturing tools such as jigs and fixtures.
DDM delivers several benefits to manufacturers including eliminating moulding and machining, introducing green manufacturing concepts and minimising waste, enabling application diversity and allowing low volume production among others.
DDM eliminates moulding, machining
Direct digital manufacturing eliminates moulding, machining, casting and forming processes. Other than a few minutes of pre-processing to prepare a production run and some light post-processing to clean up a part, DDM progresses directly from CAD data to final part.
Tasman Machinery Managing Director Dermid McKinley explains that DDM eliminates the upfront and back-end operations common to traditional methods, saving on time, cost and labour. In addition to increased efficiency, flexibility, responsiveness and affordability, DDM introduces excellent alternatives in product design, manufacturing methodology and business operations, ultimately helping local manufacturing businesses to become more competitive.
Key advantages of DDM over traditional manufacturing methods:
- Eliminates investment in tooling
- Eliminates lag time between design and production
- Eliminates design constraints
- Eliminates penalty for redesign
- Eliminates lot size minimums
Many additive manufacturing technologies are fairly ‘green’ processes as they create very little waste compared with milling processes. The manufacturer need not maintain unnecessary inventory because there is no benefit to building more than the requirement at any time.
Key environmental benefits come from not having to use harmful chemicals or vent harmful fumes into the atmosphere during the manufacturing process. The low energy consumption in producing parts via additive manufacturing is also another green benefit.
Mr McKinley points out that DDM essentially rewrites the rulebook for making manufacturing decisions, being a polar opposite to conventional production methods in many instances. This makes it a disruptive technology and more difficult to appreciate and comprehend.
DDM is either used in the manufacturing environment to manufacture finished goods or to make the components that aid in the manufacturing of the products. Mr McKinley explains that DDM is suited for low-volume manufacturing, not mass production.
The technology is still relevant for the mass producer because every manufacturer has low-volume needs in the production of manufacturing tools such as jigs, fixtures, gauges and hand tools.
Producing manufacturing tools presents the ideal opportunity to try DDM. These tools are deployed to make manufacturing and assembly fast, efficient, repeatable and cost effective. In this manufacturing context, DDM becomes a low-risk, high-return alternative to standard practices. Because the tools are used by the company, not the customer, and the time and cost to produce them is small, an unsuccessful attempt has little consequence.
But when successful, DDM has a major impact on productivity, quality and the cost of producing parts. Performing DDM of manufacturing tools is currently more popular than DDM for end-use parts.
Popular in many industries
Some of the greatest DDM successes are not in the manufacturing industry but in the medical and dental segments that have been early adopters of DDM to meet their need for custom fitting devices. Orthotics, prosthetics, hearing aids and dental bridges have all benefitted from DDM.
(Written by Scott Crump, CEO of Stratasys Inc. and Dermid McKinley, Managing Director of Tasman Machinery, Melbourne)