CAM Tools Automate Programming, Aid Five-Axis Machining and More
The right software tools can help a shop realize the full potential of its workforce so that it can better meet increasing customer expectations.
Mold manufacturers are under pressure. Shocking revelation, right? End customers demand or even expect to see increasing levels of quality, accuracy and consistency. They apply pressure to shorten delivery lead times and lower the fee that manufacturers charge for their services. As if these demands were not difficult to meet already, a shortage of employees with the necessary skills to become productive quickly complicates the situation. However, successful mold manufacturers are employing software tools and the most productive mold design and manufacturing methods to alleviate this pressure.
In speaking with some of the most successful mold manufacturers, the same challenges come up time and time again. Let’s look at key areas in manufacturing where these challenges exist that would benefit from combining emerging software technology with best practices.
It is not uncommon for mold manufacturers to have invested heavily in multiple software solutions over the years. Mastering and maintaining these systems creates many challenges like managing maintenance and training costs and deploying software updates across the manufacturing facility, for example. On a more practical note, the lack of interoperability between multiple CAM systems is a real problem. For example, there is often no easy way to transfer the state of unmachined stock from one CAM system to the next, which increases uncertainty and inefficiency in the overall process.
By consolidating to a single CAM provider, mold manufacturers can benefit from a host of instant productivity gains. Those ongoing training and maintenance costs are reduced. At the same time, the workforce becomes more flexible as it seamlessly moves from project to project by using the same CAM interface. Likewise, a single CAM solution allows multiple programmers to work on larger projects simultaneously and across multiple shifts.
In addition to the impact this has on the workforce, the most capable CAM software can offer features designed to save more time. Super-fast algorithms, high-efficiency roughing and high-speed finishing strategies all make use of 64-bit, multi-core processing so that NC code can be created quickly. As the capabilities of the CAM software improves, ever more powerful features become available. For example, powerful toolpath editing capabilities enable programmers to make localized edits to their milling paths without unnecessary toolpath re-calculations, saving hours of programming time.
Machining templates and smart macros are other keys to automating the CAM programming process. The most successful mold manufacturers have realized that they can analyze
how their engineers program their parts and that they can consolidate their best practices into a suite of macros that represent a company’s “special sauce,” or what makes its process and parts stand out in a crowd.
Instead of using a manual programming process, engineers simply select and run a macro and let their CAM software do the hard work. Macros can even interrogate the model being processed and make informed decisions about how best to program the part.
It is all well and good having the ability to create NC code quickly and to machine parts faster, but it is pointless if the part is of such low quality that it takes hours of manual polishing and benching time to finish it. Not only are these processes expensive and time consuming, they also suffer from varying levels of control and repeatability.
Let’s consider the manufacturing of large, complex molds. These are challenging to machine and often require the use of long cutting tools. As CNC machinists know, many factors impact surface finish. One factor is the length, and therefore rigidity, of the cutting tool assembly. As tool length increases, so does the likelihood of cutter push-off or vibration, which negatively impacts the accuracy and finish of the machined part.
Fortunately, five-axis machinery provides a solution. The rotary axes of the machine can be used to orientate the tool to the workpiece in a way that minimizes the length of the cutting tool. The challenge is finding the optimum configuration of the machine’s rotary axes, and having the ability to do so quickly and simply. This is where CAM software really comes into its own.
By defining a 3D model of the CNC machine tool, a digital twin of the real thing, it is possible to simulate the machining process before it goes anywhere near the actual machine. More powerful CAM software can go further still, providing tools that give programmers the option to use the virtual twin of the machine to optimize the milling paths.
Dynamic machine control tools, a product of Autodesk, are an example. Here, the programmer can load the digital version of the CNC machine tool and use drag handles to move it into different configurations. By dynamically re-orientating the rotary axes of the machine, the programmer can instantly visualize the impact it has, enabling him or her to quickly discover the optimal machine setup, while reducing tool length, avoiding collisions and keeping the machine within its travel limits. Once the CAM programmer determines the optimal configuration, he or she simply clicks a button and the software updates the toolpath to use the new orientation. With this method, there are no lengthy re-calculations or wasted time, just huge productivity gains in a matter of seconds.
Machine crashes are a machinist’s biggest nightmare. Replacing a spindle can easily cost $40,000. In addition, there is the impact that crashes have on productivity, the ability to meet customer timelines and the risk to the health and safety of the workforce. Clearly, protecting a shop’s biggest capital investment, the CNC machines, is a big deal.
Whether a mold shop is small and has a single machine tool or is a multi-million-dollar operation, it needs to have the confidence to run the NC programs knowing that they are safe. This is key. The right CAM software will take safety seriously and provide multiple layers of protection. The software might detect collisions involving the tool assembly and CAD model, or it might go further and consider collisions involving the stock. The most capable CAM programs can even identify and automatically avoid collisions by using the five axes of the machine to tilt the tool away from the machine or the workpiece and prevent hazardous moves.
Many CAM programs offer interfaces with third-party verification tools as well. In addition to checking that the G-code is safe, the best of these products will connect to the actual CNC machine tool and provide real-time protection, even when the operator is manually jogging the machine. This means that it is virtually impossible to crash the machine into itself or the workpiece. The combined effect of these tools is that manufacturers have the confidence to run their machines when the lights are out and the machines are completely unsupervised, making it possible to keep machines running overnight and during weekends.
Finding qualified people is another tough challenge. The skills gap is nothing new, and the current workforce is getting older. One approach to on-boarding new employees is to make use of the aforementioned smart macros. When new programmers have access to a library of tried-and-tested macros, they can program their first parts quickly and safely, knowing that the NC code is safe to run on the machines. This also frees up more experienced workers to focus on more challenging projects.
Combining smart macros, machining templates, tool databases and a host of other shop-wide standardizations enables new recruits to add real value to the business as quickly as possible.
Combining smart macros, machining templates, tool databases and a host of other shop-wide standardizations enables new recruits to add real value to the business as quickly as possible, often in just a matter of weeks. At the same time, by consolidating everything into a single CAM solution and embracing standardized processes across the shop floor, engineering teams have higher levels of agility, meaning projects can be completed on time and on budget.
By consolidating everything into a single CAM solution and embracing standardized processes across the shop floor, engineering teams have higher levels of agility, meaning projects can be completed on time and on budget.
One of the biggest challenges mold manufacturers face is choosing a technology from a group of emerging technologies in which to invest—for example, additive manufacturing or 3D printing, generative design, conformal cooling, cloud computing or Industry 4.0. The first step is determining which ones are right for the company and determining if those options can provide a competitive advantage.
Take conformal cooling, for example. If implemented correctly, it can have a huge impact on the molding process. The super-efficient cooling circuits in conformal cooling systems can shorten molding cycle times, reduce part warpage and save money. While there are obvious benefits, manufacturers need to balance them with the cost of hardware and current limitations. 3D printing hardware is improving at a rapid rate, but still the platforms are only capable of producing small to medium-sized parts. Forward-thinking moldmakers are starting to use 3D printing to additively manufacture cores that include the conformal cooling channels. These cores are then assembled into the finished mold, enabling a molder to use the cooling where it will have the biggest impact.
Of course, the full value of a conformal cooling system can only be realized if used alongside computational fluid dynamics (CFD)-based analytical software tools that have the ability to simulate the mold design. These physics-based tools can make highly reliable recommendations that make it possible to optimize the mold design early, ensuring the molding process performs as the machinist expects.
Mold manufacturers are under pressure to meet customer expectations in terms of speed, quality and cost. Exploiting the latest technology from innovative suppliers can give moldmakers the ability to improve how they work today and grow their confidence to become even more successful in future.
About the Contributor
Clinton Perry is a product marketing manager for Autodesk. He has more than 23 years of engineering experience, having held numerous roles within the company. During his time as a principal consultant within Autodesk’s Advanced Consultancy Group, he specialized in developing manufacturing solutions that automate the CNC machining of extremely complex parts, serving industries such as aerospace, automotive, telecommunication and consumer goods. Clinton is based in the United Kingdom and is part of Autodesk’s Digital Manufacturing Group.
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