Versatile Nakamura extends scope for EDM

The purchase of a new Nakamura-Tome AS200 turning and milling centre by a leading wire and spark electro discharge machining specialist has added value for its customers, brought work previously subcontracted back in-house and opened up new market opportunities.

The machine has been supplied by the Engineering Technology Group who are the sole UK distributor of Nakumura-Tome machines in the UK.

Silverstone based EDM Precision Technologies has always concentrated on its core EDM skills with a focus on high precision, high quality and fast turnaround high-value parts – often in exotic and expensive materials.

But, as managing director Paul Waldron explains, the investment in the Nakamura turning centre brings a new, complementary capability to the company.

“For a number of years, customers have been asking me why we didn’t do 5-axis machining, but I could see that if we went down that route we could easily start to become a 5-axis machining shop, which isn’t really what I wanted to do. I like the fact that we are an EDM company. But I realised what we were doing was putting out a lot of turning work to subcontractors.

“It seems to be the case that a lot of components that need EDM work need turning too. In many cases a turned blank was being finished on an EDM machine and we often had to get someone else to turn the blanks for us.

“So about a 9 months ago we thought why don’t we invest in a turning machine?

“Rather than investing in a simple lathe, we wanted a turning centre that would enable us to mill features onto turned parts and produce more complex components in one hit prior to them being finished on one of our fifteen CNC wire or spark erosion machines.

“This added capability would enable us to ensure high quality, fast delivery and good value on a wider variety of complex parts,” he adds.

The Nakamura-Tome AS200 is a very fast and ultra-compact Y-axis machine with a lot of milling capability on a footprint of just 1,650mm by 1,600mm. It has a 65mm bar capacity and 8” chuck capacity, a 15-driven-tool turret, 5.5kW driven-tool power, 82mm Y-axis and a maximum turning length of 300mm.

Paul Waldron says: “Some of the parts that are coming off the AS200 now are really, really good. The parts are as precise as we have had made by the top motorsport turning subcontractors. Even without the years of experience they have, the new machine has made us comparable on quality.”

He says that the machine has also allowed the company to go after more Formula One work.

“Formula One represents about 20% of our business and there were components that we were turning away as we would have been relying on outside subcontractors turning pre-EDM blanks. This was a problem.  If you subcontract out a component for a race team you are putting yourself at risk, so we were turning that work away because we didn’t do turning in-house – now we can.”

For example, on one component, EDM used a subcontractor to produce a rough blank which then required a lot of wire eroding and some spark eroding to get to the finished part. Now, rather than wire eroding the bore and outside diameter, these can be turned to the required accuracy on the AS200.

“Now we can turn the bore and the outside diameter as accurately as the drawing requires rather than wire erode them. We only spark the bits that really need sparking, which will reduce our unit cost dramatically,” says Paul Waldron.

EDM engineering manager Roy Marks took the decision to purchase the AS200 followed a fact-finding visit to MACH 2014.

“I thought it looked a really nice machine, but all the machines I had seen that could do for us what the AS200 could do were in the region of £150,000. I explained this to ETG and was brought up short when I was told that I would probably get change out of £80,000.”

Paul Waldron adds that that a decisive factor was the capability the machine could offer coupled with a very compact footprint.

“The machine has a small footprint which is very attractive for us and I’m quite surprised how much we are already putting through it – and this is all work that we were sending out.”

He adds that the fact the Nakamura is of a Japanese manufacturer was also important.

“We made a conscious decision many years ago at EDM to go with Japanese wire and spark erosion machines and we have had excellent experiences with the manufacturers.  We also liked the fact that Nakamura only makes turning machines.

“They have really focused on their core capability. All their effort and investment is in making a really good turning centre. When we told people we were buying a Nakamura their reaction was that we were buying a machine as good as you are going to get.”

Founded in 1992, EDM Precision Engineering has been based at Silverstone since 1995. Clients include six Formula One teams as well as customers in industries as diverse as medical technology, defence, aerospace and nuclear engineering.