Mitsubishi EDM is a necessity for aero manufacturer

As an end-to-end precision engineering, design and manufacturing business, Raysun Innovative Design is a company that provides services right the way from initial concept design, through prototyping and project management, on to manufacture and testing. The Rugby-based company was founded to do two main things, one side of the business is a tool room with its own design and manufacturing facility that specialises in jigs fixtures and tooling for the aerospace industry, the other division is a ‘fast make’ service that rapidly produces development parts in small quantities for gas turbines.

Like any company working in this challenging field, high-quality EDM machines are a necessity. Raysun Innovative Design is no different. It recently purchased its second Mitsubishi EDM machine, MV1200s which sits together with their already installed MV2400S with a simultaneous 6th axis rotary indexing unit from the Engineering Technology Group (ETG). Commenting upon this, Mr Charles Ray, Director at Raysun Innovative Design Ltd, says: “We purchased our second Mitsubishi machine because we had a good experience with the first machine, the larger MV2400S. This first machine was a bit of a chance for a small business like ours, buying a ‘top-end’ machine-tool. However, after we had invested, we found that we were using the machine for all kinds of applications that at first didn’t appear obvious. It rapidly became a machine that was used all of the time. The MV2400S soon became the go-to machine in the ‘fast make’ department of our business, as we realised there were a lot of applications that we could use the machine for; especially concerning gas turbine parts.”

“With some of the prestigious contracts we had secured, it seemed like the obvious and right thing to do, to purchase a machine that was dedicated to the ‘fast make’ side of the business.”

Commenting upon the relationship with HK Technologies, and subsequently the Engineering Technology Group (ETG), Mr Ray continues: “The relationship started for me many years ago. During previous employment at a company called Winbro Group Technologies, I came across the machines that required die to sink EDM equipment. Following a lengthy procurement process, the company selected the Mitsubishi EDM machine from HK Technologies. I watched that machine run very reliably for several years, so when it came to considering wire EDM, Mitsubishi was right at the top of the list as names to consider.”

“In addition to EDM, we have been involved in 3D printing for our work holding, clamping and fixturing. We’ve had various 3D printing systems as the technology has developed, and recently we bought a system from ETG that utilises either Kevlar or Carbon Fibre. For example, we have made fixtures where we can put a turbine route blade form into the printed fixture and use the fixture for laser marking. We have printed another fixture where we have applied a small chuck detail to the fixture’s underside that also has a turbine blade root form. This fixture is used as a soft fixture for CMM inspection.”

Quality Guaranteed

“The quality of the Mitsubishi machines really is the core of our business. We rely on them perhaps more heavily than we should, but if we are measuring a part on the CMM and we get a questionable result – we look at the CMM first rather than the EDM machine. This demonstrates our reliance and faith placed in this particular platform.”

When asked how the solutions have helped the company achieve NADCAP and other certification platforms, Mr Ray states: “Working with aerospace and producing parts that fly, there has been an increase in demand from our customers for us to work at the NADCAP level. The two Mitsubishi machines have made it much easier for us to work at that level than perhaps other equipment we have. The new D-Cube control system is very well set up, there is a maintenance schedule that can be contained, and we can add to it. The machine is also self-diagnosing, self-controlling and the diagnostics on board are at such a level, that the work we have to do as a user is limited to achieve a NADCAP level of work.”

Educating the team

“As an engineering group, we’ve had very limited previous knowledge of EDM. The toolmakers we employ, principally have a background in milling, turning and grinding. I wouldn’t say that EDM has been something of a black art, but it’s definitely something where there has been very little previous experience. So, when we are talking about complex manufacturing processes, which EDM is, we have one or two ways of dealing with things. We either send the guys on comprehensive training courses to understand the technology or, what has happened in our case is that we have relied heavily upon the built-in technology of the CNC units on the Mitsubishi MV1200S and MV2400S machines. The CNC control unit allows us to fill in a very limited number of fields, such as type of material, type of profile and number of cuts, the machine selects the technology that will work for us.”

Regarding the new CNC configuration on the Mitsubishi MV1200S machine, Mr Ray says: “I am not a programmer myself, but my colleagues tell me the control is considerably upgraded from the previous version on the MV2400S that was installed some years back. It is much more accessible for maintenance routines from a quality viewpoint, and we can add our own maintenance requirements into the control. The guys tell me it’s quite a similar platform, so they didn’t have to ‘go back to school’ to learn how to reuse it, but there are a lot of new features and new facilities on board. Furthermore, the visual display gives more feedback.”

Referring to the Mitsubishi EDM machines, Mr Ray continues: “The first Mitsubishi machine has almost worked non-stop for nearly five years. The machine has 6-axis capability, and this has helped because we had parts that needed to be held in a number of different configurations. The rotary axis means we can hold the part once, but then rotate it to several different positions. So, we are not using it as an active axis, but more as a positional axis. This has made us more flexible with the new work that is coming our way, and we can produce our parts with fewer setups and much faster cycle times at a lower cost.”

“If we were in the market for another wire EDM machine, which we may be in the future, there is little doubt that Mitsubishi and ETG would have to be top of the list for consideration,” concludes Mr Ray.