CAM Software Answers Need for Speed in Challenging Mold Manufacturing
P and C Tool | Meadville, PA, USA
When a custom mold builder put a new 5-Axis milling machine into production, there was excitement about what that the technology could bring to the table. Increased efficiency and accuracy, reduced setups, and better access to part features are some of well-known benefits of 5-Axis milling. However, you also need good CAM software that can support it.
Founded 23 years ago, P and C Tool has fifteen employees in its 10,000 sq.ft. Meadville, PA facility. The company focuses on the design and manufacture of custom plastic injection and diecast mold tooling. Also, P and C does general contract machining including emergency repairs, spare cores and cavities, jigs, fixtures, secondary operations and intricate aerospace parts. Its machining capabilities are also quite diverse and range from 3- and 5-Axis CNC milling, wire EDM, CNC Ram EDM, CNC turning, surface and cylindrical grinding and laser welding.
“P and C Tool was founded on the belief that there is a better way to build mold tooling – a way that provides quality tools with extremely short lead times, combines high-tech CNC processes with skilled toolmaking, and minimizes errors while maximizing machine time. With this in mind, we continue to invest in the technology that will get us there.”
Ed Leech, Director of Engineering, P and C Tool.
In 2019, P and C Tool procured a Roeders 5-Axis Milling Machine. Since P and C Tool specializes in custom designed molds, most parts are uniquely engineered to close tolerances with seal surfaces as fine as .0001". “We get into a lot of single cavity mold tools. As a result, most of the components are one-of-a kind and custom engineered - making profitability a challenge. We get one shot to make them right and it’s always in a hurry,” said Leech. In order to be profitable, Leech said they needed to keep the spindle running to minimize any idle time, as well as meet tight delivery schedules.
A problem keeping up with the capabilities of the 5-Axis mill was encountered early on due to the lack of throughput from the CAM software package that had been in use at P and C Tool for over 20 years. “We had way too much spindle downtime while parts were being programmed, and we were unable to keep pace with production requirements,” Leech said. “Again, because most everything we build is a one-off, each part needs a new program.”
So, reluctantly, because there was a comfort level in using a software package for so many years, Leech concluded that he needed to investigate new software. Watching YouTube videos is one way Leech stays abreast of the latest manufacturing technology content, and that is where he first saw a variety of hyperMILL® CAM software videos from OPEN MIND Technologies (with U.S. headquarters near Boston, MA) and became interested in learning more about the CAM system.
CAM Answers Speed Requirements and More
Leech evaluated many different CAM packages before finally pulling the trigger and acquiring hyperMILL®. He said, “hyperMILL® was clearly so much faster than everything else I tried, it made the decision an obvious one.” In addition, OPEN MIND’s demonstration team was the only CAM provider who was able to handle every off-script programming situation with ease, on the fly.” After an initial but quick ramp up period, the results have exceeded the expectations of P and C Tool not only due to hyperMILL®’s capabilities, but because of the support from OPEN MIND in making the transition as seamless as possible.
OPEN MIND Technologies' hyperMILL® software is a modular and flexible CAM solution for 2D, 3D and 5-Axis milling, mill turning and high-performance machining strategies with everything integrated in a single interface. This complete integration enables fast, easy 5-Axis programming using the latest operating concepts, reduced machining times and tool wear, improved process reliability and accurate, high quality surface finishes.
Intelligent algorithms ensure automatic tool collision detection and avoidance with hyperMILL® and challenging features such as high and steep walls, free-form surfaces and deep cavities are automatically calculated and machined with ease. Depending on the geometry and machine kinematics, a user can choose between 5-Axis machining with a fixed tool angle, automatic indexing or true simultaneous machining.
One of the greatest aspects of the transition to hyperMILL® was initially something that Leech was quite apprehensive about. Leech had previously written all of his own post processors for P and C’s machines. However, the post processor from OPEN MIND’s hyperMILL® is fully kinematically constrained and works to perfection he said. “Every time I need a tweak, I just call support at OPEN MIND and they send me a new post that I drop right in. It has saved us weeks in post processor development,” Leech continued.
Multiple CAM Benefits
P and C Tool has received a range of benefits since the switch to hyperMILL®, all which meet their speed and quality requirements while keeping the 5-Axis machine humming. Toolpath calculation and post processing time is two to three times as fast as their previous software. Leech noted, “And besides simply being faster, this allows for greater experimentation and trial of different creative methods because there is not a long wait for a complex toolpath to calculate.” P and C can try new things and alternative solutions without bogging down the programming process. Additionally, toolpaths are not just calculated fast – they also run fast on the machine. Leech said there is virtually no "air cutting" or tool breakage, even when stepping down from one end mill to smaller end mills in hardened steel. hyperMILL® keeps track of the stock and keeps the tool in the cut.
2+2 die cast family tool. An example of an extremely detailed parting line with inside corners milled to .0078”. With a texture requirement on the molding surfaces, it is often harder to keep a toolpath off of those surfaces than it is to machine them. The ease of adding extension surfaces and stop surfaces with programmable offsets in hyperMILL® let us finish the shutoffs right up to the molding.
Multiple toolpaths can now be worked on simultaneously, allowing the programmer to quickly jump from one to the next while toolpaths are calculating in the background. “We can even have many different parts open and work on them concurrently with one hyperMILL® seat.”
The post processor that OPEN MIND built for P and C Tool is so safe and secure, Leech can run parts without worrying about crashes. He continuously puts new parts and programs into the machine and leaves the milling operation unattended for up to ten hours so that there is time for other projects, including programming the next part. Leech said, “hyperMILL® has tamed the complexity of 5-Axis machining so that even one-of-a-kind parts feel more like production work.”
Versatility is another aspect of hyperMILL® that P and C Tool appreciates. Because the software is not tied to a strict, level-based stock progression they can mix and match stocks, geometries, parts, cover surfaces and guiding surfaces within a single program.
Taking advantage of hyperMILL®'s trochoidal (high performance roughing) toolpaths has been impressive to say the least. Leech said, “With a single click of the high-performance tab, this toolpath strategy keeps the tool buried deep in steel without breaking the end mill.”
The tool library in hyperMILL® is integral to functionality, and is fast and easy to use. It is located up front for adding new tools, reusing old tools, creating different toolholders, modifying tool lengths, and setting up limitless amounts of materials, cutting parameters, and machines. Leech said, “But the best part is keeping an exact representation of every tool in every machine for quick and easy retrieval and use.”
Tremendous Toolpath Strategies
“The 5-Axis rest machining toolpath alone is worth the price of admission,” Leech continued. It performs 5 -Axis "pencil milling" where the previous tool size and the surfaces to be machined are selected, and then hyperMILL® generates a 5-Axis toolpath that flows around all corners – in comparison, the previous software’s toolpath was quirky, inefficient and generated spotty results. “hyperMILL®’s 5-axis rest machining is super-fast and smooth, and I very rarely have to manually input any 5-axis control over it. There is even a ‘smooth overlap’ option that feathers the cut of a smaller tool into the larger tool so there isn't a mismatch,” said Leech. He points out that a .0001" mismatch between end mills can visually look much bigger than it really is, and the hyperMILL® smooth overlap strategy helps to eliminate that problem.
4+4 Family Tool. In other software Ed Leech seen a lot of air-cutting when stepping down from one end mill to the next, especially on small detailed areas and deep grooves. The deep grooves in these cavities were roughed with a .039” toric end mill and there was virtually no air-cutting and zero tool breakage,s even though the previous tool was a .118 ball end mill.
“hyperMILL® has cut our 5-Axis programing time in half or more – we can keep up with the Roeders machine now,” said Leech. “And it has also improved our toolpaths, so the cut time is faster.” Since it is a two-fold increase in speed, P and C has increased the type of milling work they can do and increased profitability, even allowing them the opportunity to take on higher cavitation work while still keeping up with their single cavity jobs. The quality of the work has also been improved, minimizing the need for additional EDM and grinding operations.
Single cavity, custom tools can be challenging to say the least. New CAM programs are required for each component and hyperMILL® has helped to ease the bottleneck in programming for P and C Tool. Leech reports they have easily seen a 50% increase in throughput on 5- axis work since using hyperMILL®.
Thermoset over-mold cavities milled complete. hyperMILL® really generates a beautiful surface finish with little effort. The lead-in and lead-outs (hyperMILL calls them macros) on the toolpaths are extremely smooth. I also utilized the “smooth overlap” function so there is no noticeable line when switching between Z level and contouring cuts.