Manufacturing Engineering: The latest PowerMill 2019 update from Autodesk adds a new additive plug-in module. Can you describe this “high-rate” additive manufacturing system and how it works?
Clinton Perry: PowerMill 2019 provides a dedicated suite of tools to program high-rate additive processes—commonly known as directed energy deposition [DED]. The DED process utilizes a CNC machine tool or industrial robot that can focus a power source—typically laser, arc or electron-beam—at a point in space. At the same time, material [in either metal powder or wire form] is fed into the ‘hot spot.’ The power source causes the material to melt, forming a molten puddle. By maneuvering this puddle around it is possible to build 3D shapes—and do so in a highly controlled fashion.
Those familiar with powder-bed 3D printers know that they can produce incredibly intricate 3D forms. However, the underlying technology means that they are limited in terms of material deposition rates and the size of part that can be produced. These limitations have impacted the adoption of this form of additive manufacturing in certain industries and applications.
By comparison, the DED process uses higher power levels and material flow rates, resulting in substantially higher deposition rates, allowing parts to be built faster. In addition, the larger working envelope provided by CNC machines and robots means that DED can build significantly larger parts. These two key features make DED a cost-effective solution to produce large-scale components commonly seen in industries such as aerospace, power generation and so on.
Driving a DED process requires highly specialized toolpaths that control exactly how and where material is deposited, while avoiding any localized overbuild. PowerMill 2019 sees the provision of a dedicated suite of tools to create, control and simulate deposition strategies to help manufacturers to exploit the potential of DED.
ME: What are some of the advantages offered by hybrid type CNC/AM machines over pure CNCs or traditional additive systems?
Perry: Most mainstream CNC machine tool manufacturers have begun offering hybrid machines that can deliver both additive and subtractive technology. There are some obvious benefits; a single hybrid machine tool will occupy less floor space, help reduce part setup time, and minimize the risk of human error. However, the real benefits are much more fundamental.
With separate additive and subtractive workflows, a part will typically be fully deposited before transferring to a CNC machine for precision milling. While this is also achievable with hybrid machines, greater flexibility means the two processes can be combined in alternative ways.
For example, a part may be partially deposited before CNC milling critical features. The build and cut phases are then alternated until the part is finished. Combining the technologies in this way allows hybrid machines to produce parts that can’t be produced with separate machines.
A notable example of this was recently showcased at Autodesk’s UK Advanced Manufacturing facility, where a Hamuel Reichenbacher HSTM 150 HD hybrid machine was used to repair a damaged aerospace compressor disk. The process began by CNC milling away the damaged tips of the blades on the disk before using a laser and powder form of DED to deposit titanium to replace the material machined away. Finally, the machine used highly accurate probing to measure and CNC mill the excess material, leaving a near-perfect blend between old and new material.
ME: The new PowerMill Additive system targets both three and five-axis machining systems plus robots. How does it differ when used with CNCs or with robots?
Perry: As far as toolpath creation is concerned, there are no differences whatsoever. PowerMill’s additive toolpaths can be run on a CNC machine tool or robot. A range of additive strategies is supplied to serve the following applications:
- Creating 2D toolpaths to build complete, prismatic shapes.
- Producing three or five-axis strategies to add localized features to existing parts [e.g., add lugs onto the side of an aero-engine casing].
- Generating three or five-axis motion to add coatings to parts either fully or in localized regions [e.g., adding a wear-resistant coating to a part that experiences high levels of abrasion].
The additive strategies are created in the same interface as used to produce subtractive toolpaths. This means they can be optimized using PowerMill’s toolpath editing tools. In addition, PowerMill allows key process parameters, such as laser power, powder flow rate and gas flow, to be edited on a point-by-point basis.
Once toolpaths have been produced and optimized, they can be simulated using a virtual twin of the CNC machine tool/robot, allowing problematic machine motion, such as axis reversals and/or over-travel, to be identified and avoided.
Finally, PowerMill allows toolpaths to be exported to Autodesk Netfabb simulation for a more in-depth analysis of the entire build process, including thermal and stress-related review. This gives manufacturers increased confidence that the building process will produce good parts.
ME: What customers or what industries or applications are using the system?
Perry: AM offers substantial benefits to many industries, including aerospace, oil and gas, mold and die, power generation, motor-sport, and marine. The Port of Rotterdam is one of the busiest shipping hubs in the world and a focal point for large vessels that require maintenance. If a commercial cargo vessel is stranded in dock waiting for a replacement part, it can cost literally millions of dollars in lost business. The traditional approach would be to build warehouses at key locations around the world and fill with spare parts—just in case they’re needed.
The RAMLAB [Rotterdam Additive Manufacturing Lab] team recognized the potential to use DED and hybrid manufacturing to produce replacement parts on demand when and where needed.
Their first project saw the creation of a bronze-alloy propeller measuring more than 5′ [1.5 m] in diameter and requiring more than 400 kg of material to be deposited. The finished propeller was put through exhaustive tests before being certified by the governing authority as seaworthy—a world’s first for an additively manufactured propeller! By producing parts in this way, RAMLAB can reduce the time that a cargo vessel is out of service. As well as avoiding millions of dollars of delays, it also removes the need for a network of fully stocked warehouses.
ME: What other new features will machinists find in PowerMill 2019 for traditional machining?
Perry: The software includes several enhancements for subtractive manufacturing. PowerMill has offered five-axis collision avoidance for many years, meaning toolpaths can be created that avoid collisions or near-misses involving the cutting tool assembly. In previous releases, the user could choose from a range of different avoidance options. The choice made depended on the shape of part being machined and strategy being used. PowerMill 2019 includes a new ‘automatic’ tool-axis tilting option that works on all toolpath types and all model shapes. This makes it simpler for programmers to create safe five-axis NC code, and is particularly suited to users that may be new to five-axis machining.
PowerMill’s Vortex high-efficiency roughing strategy has been enhanced to offer a new ‘from stock’ option. Based on Autodesk’s adaptive clearing functionality, this creates toolpaths with offsets based on the shape of stock being machined and typically results in reduced cycle times. In tests, a P20 core insert was machined using the new ‘from stock’ option and the previous ‘from model’ toolpath type. The ‘from stock’ option had a cycle time that was 33% faster.
ViewMill is PowerMill’s stock simulation tool. It displays a realistic representation of the stock at any point in the machining process. With the release of PowerMill 2019, ViewMill includes a new thickness shading mode that makes it easier for programmers to visualize the distribution of unmachined stock on their parts. A series of dynamic slider bars allows the color of the simulation to be changed to instantly identify surfaces that have been finished, as well as showing regions where remaining material needs to be removed or localized areas where gouges may have occurred. The improvement gives programmers greater confidence that parts will be fully machined when removed from the machine tool.
PowerMill 2019 also includes the ability to export critical manufacturing data to Autodesk Fusion Production, a cloud-based tool that allows manufacturers to schedule work, track jobs and monitor CNC machine utilization. Fusion Production allows key project stakeholders to access key information about the status of a manufacturing facility, allowing bottlenecks to be identified, processes to be reviewed and improved, and overall equipment efficiency to be maximized. Being a cloud-based system, Fusion Production allows data to be accessed anytime, anywhere and on practically any mobile or desktop device.
Metrology developer Hexagon Manufacturing Intelligence (North Kingstown, RI) has launched its PC-DMIS 2018 R1 update of the company’s measurement software, which includes the first of two PC-DMIS releases scheduled for 2018.
PC-DMIS 2018 R1 allows users to convert AutoFeatures to points or use the measured hits for new constructions and dimensions, available for plane, circle, and cylinder AutoFeatures, the company said. By converting each hit to a vector point, the optimize path feature can be used to enhance the order of point measurement, reducing the number of probe tip changes and overall measurement time. New support for Q-DAS Traces enables easier analysis of PC-DMIS data. The new QuickSet control allows users to use both QuickFeature and GD&T Selection and still have the ability to modify measurement strategies.
“With PC-DMIS 2018 R1, we fulfill our commitment to add the most highly requested items from the user ‘Idea Center,’” said Ken Woodbine, product line manager for Metrology Software at Hexagon Manufacturing Intelligence. “These include the graphical point manipulation feature and the ‘push-to-points’ AutoFeature functionality. We also introduce integration with the industry-standard Q-DAS software so key process parameters affecting quality can be identified and tracked.”
Enhanced speed of QuickFeature measurement enables users to create multiple circles and cylinders with one click, optimized for bolt hole patterns or whenever surfaces contain multiple features of the same size and shape, according to the company. The system also introduces improved Flush and Gap AutoFeature workflow for point cloud inspection.
An iOS version of CorelCAD Mobile from Corel Corp. (Ottawa, ON) is now available for the iPhone and iPad, providing technical designers with CAD capabilities to boost productivity on the go. The new CorelCAD Mobile for iOS now gives users options for both Apple devices and Android mobile systems, offering in-the-field users access to 2D design and annotation tools for tablets and smartphones.
CorelCAD Mobile is a standalone CAD designed to complement the CorelCAD 2018 desktop application for Windows and Mac. CorelCAD Mobile subscribers receive a set of 2D drawing, editing, and 3D viewing tools, full annotation capabilities, and more. For users looking for a lighter feature set, a free version is also available with simplified capabilities, including 2D and 3D.DWG viewing and basic annotation.
CorelCAD Mobile offers users the ability to sketch ideas on the go, share designs between desktop and mobile, make meetings more efficient, annotate drawings on-site, and make modifications to drawings as needed. The software is now available for iPhone and iPad on the Apple App Store and for Android on the Google Play Store. Subscriptions are priced at $99.99 or $9.99 per month. Free simple mode versions are also available.
The latest WorkNC 2018 R1 CAM software update from Vero Software (Gloucester, UK, and Tuscaloosa, AL) includes not only its new WorkNC Designer “CAD for CAM” direct modeling CAD system but also a new Robot Module. As robots are becoming more commonplace on the shop floor, there is an increasing need to provide offline programming for them, according to WorkNC Brand Manager Miguel Johann.
“New simulation and singularity resolution tools in WorkNC 2018 R1 mean users can take full advantage of the enormous benefits robots bring to the manufacturing process,” Johann said. “For example, they free toolpaths from the limitations of milling, as the tool at the end of the robot’s arm can also be a grinder, a laser head, a welding nozzle, or any other tool that engineering creativity can think of.”
Robots also allow for the tool to be fixed and the part to be moved around it, instead of the traditional method of a fixed component and moving tool, Johann said. “But robots are only as good as the software programming them, and this latest development in WorkNC 2018 R1 ensures that manufacturers can be at the cutting edge of robot technology.”
WorkNC also has new features incorporated into Waveform Roughing that improve efficiency and performance, including support for new tools in trochoidal machining strategies.
Software Update is edited by Senior Editor Patrick Waurzyniak.