Mastering multi-axis machining

FGP Systems, a subsidiary of the FGP Group, explains how Mastercam’s CAD/CAM software simplifies its multi-axis machining of turbine blades.

FGP Systems’ operations and engineering director, Simon Griffiths-Hughes has been with the company for 24 years. From machine operator to off-line programmer, to director of engineering to his current role, he has witnessed the evolution of machining capabilities at FGP’s Dorset facility. That evolution has been driven in part by Mastercam CAD/CAM software.

“We took the plunge into full 5-axis machining 20 years ago,” begins Griffiths-Hughes. “We needed something to compliment the capability of our 5-axis machine. Mastercam was the right package to support our journey. We’ve not faltered from it or 5-axis machining since that point. We’ve been using the software for 20 years.”

FGP Systems uses Mastercam 2022 and stays current with new software releases. The company’s facility houses 18 5-axis machines and a total of 63 CNC machines, including 3-axis and 4-axis models.

Some years ago, a customer approached the FGP engineering team about machining turbines. The manufacturer agreed to take on the job, but initial part programming time was extensive. The company needed CAD/CAM software that could fully support turbine machining. After researching several options, FGP Systems chose Mastercam Blade Expert. The software interface provides a comprehensive solution for various blade configurations and follows the Mastercam standard used by all multi-axis toolpaths, ensuring a short learning curve and successful deployment. It turns multiblade machining challenges into routine solutions by facilitating the removal of material from between blades, and the finish of blades, splitters, floor and fillets.

“Blade Expert is so intuitive and easy to use that it was an overnight revelation for us,” says Griffiths-Hughes. “It made programming that much easier. It has evolved from that point of every iteration of Mastercam and Blade Expert, and it is customisable.”

Cutting a dash

FGP Systems manufactures a wide range of turbines, from numerous blade types to scroll turbines. Every scroll-type turbine the company produces contains a splitter or multi-splitters. Before adopting the CAD/CAM add-on feature, working around the splitters proved difficult. The software provided a much-needed solution.

“Within Blade Expert, you can literally pick as many splitter blades as you wish and it will work out to that point,” states Griffiths-Hughes. “The machine strategies within Blade Expert are easy to set. If we figure out a strategy for a titanium blade, then we can pass that down to our engineers. We tell them that this is the strategy we wish to use on all titanium blades to get the right surface finish, part quality, and return from our Blade Expert investment.” 

Several years ago, to accommodate the influx of new jobs, FGP recruited additional engineering department employees. CAD/CAM software was a key consideration during that recruitment. Not all new staff members used Mastercam in the past, so the software’s ease of use was beneficial. The uptake and learning seemed to be intuitive, said Griffiths-Hughes, so there was no downtime and minimal support was needed to train new employees.

In addition to ease of use, the software’s integrated CAD for CAM capabilities allowed the import of files from virtually any computer-aided design source. Mastercam includes a comprehensive selection of CAD model importers and the suite of tools in Model Prep allows for modification of solids.

“I wouldn’t necessarily take work on unless it came with a customer solid model,” says Griffiths-Hughes. “That’s been the case with every one of these turbines. Not that we couldn’t model it up, it’s just that using a solid model results in a quicker process. Lead-times for turbines tend to be 10-12 weeks. We are lucky enough to be customer CAD-model driven. Typically, we import CAD models into the Mastercam environment.”

According to Griffiths-Hughes, once one turbine is manufactured, the turbines that follow tend to be similar. After the first part is produced, the challenge lies in effectively machining the gap between the blades. The main blade, splitter blade, depth of cut, and machining strategy vary between the aluminiums and the titaniums, but Blade Expert provides the ability to bear those toolpath strategies to metal. It controls depth of cut, root radiuses, and stock removal.

At FGP, turbines are manufactured from billet forms. As the billet form is machined, a stereolithography (STL) file background is created and stock removal is closely monitored.

“It’s important to know what material has been machined away within the application software and the main plane with Mastercam,” notes Griffiths-Hughes. “It is crucial to see how much material you removed with that singular tool, how much material is left to be machined, and specific cuts.”

While onboarding new stock, a machinist has a detailed view of the current job and can compare the STL model to the finished part model and can see if the part is completely machined or has remaining stock.

A dream team

Additional benefits of FGP’s CAD/CAM investment include software support. The experts at Mastercam UK play a large role in the manufacturer’s success. “If we ever need help, they’re always there to support us,” says Griffiths-Hughes of the Mastercam UK team. “Our Reseller’s software training support is invaluable. From a post processor support point to answering day-to-day technical questions, the people at Mastercam UK are always there with very quick response.”

Reliable customer support came in handy over the past two decades, especially when FGP Systems first delved into multi-axis machining. Transitioning from 3-axis to multi-axis machining was a learning process that remained manageable.

“We were straight in the deep end with full 5-axis machining,” explains Griffiths-Hughes. “I don’t think that the learning curve for multi-axis machining was massive. You must embrace the fact that it’s not just about the CAM package itself - it’s the CAM package, the machine tool, and the post processor. If you get all three elements correctly, it can work for you. If you don’t invest the time and effort into getting the best out of the CAM package, and the best post processor which is supported through the software, then you could fail quite easily.”

Reaping the benefits

Embracing multi-axis machining allows FGP Systems to take on challenging parts and expand its customer base, he adds.

“If we didn’t have the full advantage of the 5-axis machining and the supporting CAD/CAM package, we wouldn’t have been successful. We would have been brave enough to take the part on, but we wouldn’t have succeeded. So, we’ve taken on parts that previously we wouldn’t have.”

FGP Systems continues to reap the benefits of multi-axis machining, including reduced set-up work, improved accuracy, better surface finishes, and the ability to machine new, complex parts. The versatility of multi-axis machining allows the machining of simple parts as well.

“I’m not saying that turbines are complex nowadays - with the use of Blade Expert, they’re not,” Griffiths-Hughes concludes. “Some of the housings that we’ve done over the last few years are incredibly complex, but Mastercam and 5-axis machines have allowed us to be competitive and be successful with those parts.”

Griffiths-Hughes would have no trouble presenting an engineer with a solid 3-axis background with an intense introduction to Mastercam and asking him to program 5-axis toolpaths in a fortnight. At FGP Systems, CAD/CAM software continues to make 5-axis machining of both complex and simple parts attainable and cost-effective.

www.mastercam.co.uk