René Raaijmakers
20 January 2017

The cost savings that Hittech’s smart machining approach achieves are often spectacular. ‘We’re good at peeling complex parts down to their cost price. We use continuous roadmaps to provide value engineering.’

In 2012 ASML asked Marco Verloop and Koen Mentink to come to Veldhoven and share their vision on 3D metal printing. The Hittech directors made an agreement beforehand: at a strategic moment during Verloop’s presentation, Mentink would place a 3D part on the table.

At Hittech, you see, they’d been thinking for a while about no longer machining a part known as the E-Box, but rather printing the part using additive manufacturing techniques. They’d already talked about it with ASML before. To Verloop and Mentink, 3D seemed to be the obvious way, given the numerous cooling channels that were hard to create through machining – but it had never quite gotten the go-ahead. Hittech decided to invest in a special pilot project to convince its customer.

When Mentink placed the part on the table, the metal print instantly became the centre of attention. All the more so when Verloop’s presentation demonstrated that the 3D-printed E-Box also met all the technical specs.

Detail of 3D-printed structures

Genes

There’s always hesitation with any new technology. ‘Customers view a new technology much more critically. But as soon as we have something tangible, we can instantly skip over a huge part of the conversation,’ says Verloop. That’s why Hittech regularly frees up time and money for a development project to test alternative manufacturing routes. At its own risk.

 advertorial 

Machine Learning Conference: limited number of visitors

The second edition of the conference brings together industrial and scientific specialists who are applying ML techniques in high tech domains, or are interested in doing so. Keynote by Nicolas Lehment (NXP). Other sessions by ASML, TUE, Quby, Ghent University, Grai Matter Labs, Edgise and Verhaert AI Lab. There are only 13 seats left, so register in time!

Hittech’s engineers are steeped in making these kinds of deliberations and searching for new ways to reduce costs. They continually review production methods. ‘We’re good at peeling complex parts down to their cost price. We have roadmaps for continuous cost reduction and we work proactively with our customers to bring down the price. We don’t wait until our customers say they’ve found a competitor who can do it better.’

Hittech calls this approach smart machining. Its engineering teams continuously work to optimize production processes and lower costs. Verloop claims that Hittech’s approach sometimes delivers savings of up to 30 per cent. ‘In the case of 3D-printed parts, we reduced turnaround from twenty-one weeks to just five or six.’

Sizeable reductions in cost also mean a drop in revenue and machine occupancy in Hittech’s plants. ‘In most cases, squeezing out costs works against us,’ Verloop admits. ‘Look at 3D. If we hand our British partner 3T RPD a titanium part to print, that reduces our machines’ occupancy and we’re outsourcing work.’

Yet it’s the right approach, he says. ‘Proactive efforts generate trust and enhance our relationship with customers. So we keep coming up with proposals that aren’t automatically good for us.’ Mentink adds: ‘Ultimately it’s better for our customers and thus for us, too. Customers know that if they want value engineering, we’re who they need. It’s automatic with us; it’s in our genes and they don’t have to micromanage it.’

Out of the box

Verloop gives another example: the production of the carrier handler Hittech is making for ASML’s wafer handler module. ASML had already contracted VDL ETG to manufacture the entire wafer handler, but in 2015 it also charged the company with full responsibility for developing this system component.

In theory, the Netherlands’ largest supplier could also have taken on the production of the carrier handler itself, but it decided not to after reviewing Hittech’s value engineering proposals to lower the cost. An important part of that was Hittech’s smart machining approach, which combines casting with milling.

That approach doesn’t mean there’s a one-sided focus on new technologies, Mentink notes. The teams examine manufacturing projects with an open mind and weigh all the options – including both traditional and new technologies. And the best choice frequently isn’t a new technology like 3D printing.

Mentink gives an example in which his people used smart design and mounting methods to create specific parts using three-axis machines instead of five-axis ones. That not only reduced costs thanks to the lower price tag for time on a three-axis machine, but also raised accuracy through the lower tolerances that were achieved.

Hittech constantly works with suppliers of tools and CAM programs to develop new cost-reduction strategies. ‘We’re constantly calculating maxima in which we weigh factors such as the machine’s cost and the tools used,’ says Mentink. ‘Sometimes a more expensive mill can lower your total machining costs.’

The engineers strive to approach the parts manufacturing strategy with as little bias as they can. Mentink gives an example in which Hittech reviewed the production of a very complex titanium milling component using this out-of-the-box approach. ‘If we tried to cover everything based on finite elements and risk assessments, we’d need twenty steps to make this part,’ he says. ‘That’s how it often goes. If you sit down with a group of specialists and analyze everything that can go wrong, the problems that crop up are myriad.’

At Hittech they decided to take a step back instead, Mentink says. ‘We asked ourselves: suppose we didn’t have those problems? Then we ended up with four manufacturing steps. In covering every possible risk we had twenty-one, but the likelihood that it would go wrong was in most cases small. By just taking the gamble and trying out a few quick manufacturing routes, we ultimately ended up with eight steps, without any of the risks we’d previously identified actually occurring. Eight isn’t bad; we know our competition needs many more.’

Constructing the carrier handler: casting moulds, castings, finished castings and the fully assembled product (from left to right)

3D&FPP

To stay at the forefront in applying new technologies, Hittech also needs to invest in researching their potential. To do that, the company seeks to collaborate with research institutes and customers. One good example is STW’s Mobius project, titled Additive Manufacturing of Complex Precision Flexure Mechanisms, in which the company is working with TU Delft, the University of Twente and ASML to investigate the possible use of 3D metal printing to create flexures. The objective is to be able to print integrated mechanisms in the future. In order to use these technologies, it’s important not only to know the ultimate application, but also to devote sufficient attention to the production process itself.

To that end, Hittech and Innovationquarter recently took the initiative in founding a European consortium for integrated post-processing of 3D metal prints. The project bears the name Integrating Metal 3D Printing and Flexible Post-Processing (3D&FPP) and has been granted a subsidy of two million euros by the Interreg 2 Seas 2014-2020 programme, cofunded by the European Regional Development Fund. Hittech is conducting the project with several companies and research institutes in England, Belgium, France and the Netherlands. ‘We’re making sure that a few years from now, we can use this technology to keep furthering our ideas,’ says Verloop.

The integrated post-processing that Hittech is developing in 3D&FPP can in theory be used for various manufacturing methods that start with a material-saving pre-form or near net shape, such as casting, welding and laser cladding. ‘These are parts that are close to being a final product, but they have the problem that they still need some work. You have to measure the parts accurately to determine how they deviate from the desired final result, write a machine program and make special fixtures. Only then can you begin post-processing. So you start with a very flexible process, but you lose flexibility because of the complex post-processing. We see that as one of the major problems of the future, and that’s why we started 3D&FPP.’

The consortium’s objective is to achieve flexible clamping for near net shapes on the finishing machine. The piece doesn’t have to be mounted with great accuracy; the idea is that the machine will first scan the intermediate product and compare it with the intended design. ‘If the machine knows exactly where the inaccuracies are, that information can be directly translated into a milling program. A five-axis machine can then determine the zero point itself and do the milling,’ says Verloop. ‘Through the Interreg project, we’re preparing for the next phase in smart machining.’