All posts filed under: Additive Fabrication

The Complexity of Rapid Prototyping

The complexity of the geometry required for rapid prototyping is fuzzy. The only things indisputable are limited cases. The choices for inexpensive CNC equipment are large. These machines use improved software and address the recent market for rapid prototyping. This equipment does require a basic knowledge of machining. When the end result has compound surfaces and complex curves additive technology is the obvious choice. This method may not work for the final material but will avoid complex set ups, calculations and numerous daunting tasks. If the part with an accurate reflection of the desired geometry is obtained, they are many different ways to change it into another material. Additive technologies are an excellent choice due to the complex shapes in the world. The majority of consumer products from shampoo bottles to automobile parts would be very hard to make without machine subtractive. Many items are hard to describe externally, internally and mathematically. A lot of parts have an odd shape making them difficult to machine. This is just as true for items such as jewelry, …

Patent Applications for Additive in the United States

There are 6,000 patent documents in the United States regarding additive fabrication. This means the straightforward approach is over and it is almost impossible to prevent one worker from interfering with another. Cross licensing and licensing have become common and now requires a strategy for intellectual property regarding technology and business plans. Most of these patents are to gather competitive intelligence for a defensive and offensive strategy. When benefits are ignored they go to the competitors. Competitors can shut each other down and restrict freedom. The use of intellectual property must be understood to avoid trouble and compete effectively. Most companies do not pay attention to competitors. This can result in an erosion of the company’s place in the technological market. Competitive intelligence is gathering and analyzing information gained from public sources. It is easy to find a competitors brochures, new releases, trade press articles, white papers and SEC filings. The top of the list should be patents. The Importance of the Patent Patents provide information not found anywhere else and the material they contain …

Accuracy and Precision

Accuracy is the difference between the intended and actual finished dimension. There are accuracy specifications for linear dimensions, flatness and whole sizes. This issue is critical and additive technologies have improved the standards. The process is complex because additive methods are all different, the cutting tool is used as a point of reference, there are multiple operations, a complex chemistry and energy exchanges to consider. Subtractive technology is incorporated using additive technologies. This becomes an important part of the process and increases the absolute accuracy. This is because any compounded errors due to the additive process can be corrected using subtractive technology. This is the reason the method based on an inkjet has a distinctive edge. The parts produced are equal to or near CNC accuracy. The versatility of the materials and the speed are the tradeoffs for other RP methods. The majority of the other methods are within approximately a few millimeters. A qualitative idea can be established by beginning with stereolithography because the results are accurate. Powder and LOM methods have less accuracy. …

Additive Technologies in Injection Molds

Injection molds can be produced faster and at lower costs using additive technologies rather than subtractive technology. In addition, additively produced tools can be used to indicate the performance of a final hardened tool. The use of additively-fabricated molds can create plastic components by the dozens, and in some cases, the millions, to be used for prototypes or testing. Subtractive CNC or spark erosion drawbacks: Methods are slow and expensive. Skilled workers for these methods are in short supply. Product complexity is high, product cycles are short. More precise tools are needed from declining supply of toolmakers. Benefits of Additive Technology The benefits of the process of additive technology in injection molds include saving time and labor. In addition, additive technologies can provide the option of improving mold performance that supersedes subtractive technologies. It provides the ability to build conformal cooling channels which assist with increased thermal performance. It also allows for the use of multiple or gradient materials which optimizes the performance of molds. These benefits decrease cost and may be a revolutionary development …

Metal Castings – Investment Castings

Additive technologies involve the use of injection molds which can produce components faster and at lower costs than the traditional use of subtractive technology. Additive technologies can be utilized as investment casting patterns. Casting methods are one of the first industrial processes developed by humans and have been utilized for thousands of years. The results can yield detailed and intricate results. One of the first materials used for the casting process was bees wax. This process is so adaptable that the forms of the bees have been used as patterns for producing detailed and stunning gold jewelry. One of the modern applications for additive casting patterns is creating environmentally friendly and socially conscious jewelry. On the other end of the spectrum, applications for casting patterns have produced products that contain a variety of metals and can weigh several hundred pounds. Additive casting patterns involve a thick coating or investing, which is a pattern that melts or burns out quickly as opposed to a material like ceramic, which doesn’t. A gate can be built into the …

Direct Additive Fabrication of Metal Parts and Injection Molds

There are many ways to apply direct additive fabrication of metal parts and injection molds which are as follows: Laser Sintering – used frequently to create today’s tools and metal parts. A supplier that exclusively focuses on this process makes systems that are mainly dedicated to metal or plastic materials. It provides a range of metal material that include titanium, nickel alloys, cobalt chrome, aluminum, and stainless and hardened steels. Selective Laser Melting(SLM) – is similar to laser sintering; however, ceramic powders or fully melts metal directly form fully dense parts. No steps of post processing, such as infiltration or burnout, are needed as with the production of porous parts by laser sintering even though it’s still necessary for some finish machining. Electron Beam Melting(EBM) – originally developed at the Chalmers University, this process is powder based in which has much in common with laser sintering. However, the laser is replaced with a scanned 4KW electron beam that makes fully dense parts. Available material includes pure titanium, titanium alloy (Ti-6A1-4V), Arcam Low Alloy Steel, and …

Functional Parts and Tools by Additive Fabrication – Direct Fabrication and Indirect or Secondary Processes

Additive fabrication is a class of manufacturing procedures where a part is built by adding material layers upon one another. This process has been evolutionary in different manufacturing applications. And as a result, it is now an accepted solution in fabricating customized, geometrically complex, or low volume parts, and it’s recognizable in producing tools and parts that are not possible to combine and form into various materials. Though many applications are hidden from the public and are still in development, their ranges are potentially vast. Even some of the technology’s liabilities are transformed into advantages. Also, additive technology is utilized by directly fabricating items, such as molds and parts, or it is utilized through secondary or indirect purposes. Direct Fabrication Plastic and metal parts are often directly fabricated. With plastic parts, stereolithography, thermoplastic extrusion methods, and laser sintering (LS) are currently the most important forms used in direct fabrication. Stereolithography is a process in creating objects that are three dimensional with using a laser beam controlled by a computer that builds the required structure from …