Smarter set-ups with new EDM

A precision machining subcontractor has invested in its first Sodick wire erosion machine, a VL600Q model supplied by Sodi-Tech EDM.

Berkshire-based Duckworth & Kent (Reading) is using the machine to advance its wire erosion capabilities, reduce the number of set-ups required, improve quality and repeatability, and introduce unmanned overnight operations.

With 52 years’ experience, Duckworth & Kent’s extensive skills enable the company to undertake everything from prototype projects and the development and manufacture of special purpose machinery, through to small batch and full production piece-part machining.

“Our speciality is low-volume, high-quality precision components, often manufactured from a variety of difficult materials and with complex shapes that few others want to attempt,” explains sales director Stuart Gleeson, son of original co-founder David, who retired in 2000. Stuart’s brother, Terry, is the current managing director.

The 15-employee business has relied on wire EDM for many years, particularly for the extremely high accuracy cutting of precision parts. However, when one of the company’s three wire EDMs recently required replacement, the company decided to evaluate a range of potential suppliers.

Reviewing three wire EDM machines, Mr Gleeson and his team quickly settled on the Sodick VL600Q, which seemed, “a natural fit with the type of work” undertaken at the company.

“Unlike certain other machines, the generator on the Sodick model features state-of-the-art technology,” Mr Gleeson he says. “In addition, we liked the rotary-axis, which knew would help with complex parts. We did some capability trials and promptly ordered the machine.”

The Sodick VL600Q offers travel in the X-, Y- and Z-axes of 600 x 400 x 270mm respectively, with 90 by 90mm U/V-axis travel. Installed in June 2019, Sodi-Tech EDM provided both onsite and offsite training.

“We’ve been putting the rotary axis to good use,” says Mr Gleeson. “For instance, it’s making light work of a lifting rod for the defence industry that is made from toughened steel. The rod features a series of diameters and squares that have to be concentric and straight to one another. There is also a thread and a yoke at the top for lifting.

“The rod is about 150mm long and we recently produced a batch of 58 in a single set-up. Previously, this part would have required two EDM operations, or one EDM operation followed by milling and/or grinding. Saving a set-up probably equates to a cycle time reduction of one hour per part – so that’s 58 hours saved on one job alone, plus the quality is better as we avoid picking up the component and resetting.”

Stuart Gleeson, who joined the business in 2001, knows a thing or two about the defence industry having been apprentice-trained with the MoD as a precision fitter.

Another defence-related job at Duckworth & Kent involves the wire eroding of discs from exotic plate materials such as vanadium, tantalum and molybdenum. Measuring 50mm in diameter and 2mm thick, the plates are used as test samples.

“Such is the versatility of the Sodick machine that we have also used it to cut through assemblies intended for special purpose machinery,” adds Mr Gleeson. “These assemblies comprise a hard steel part featuring a titanium nitride coating, magnets and conductive adhesive.

The Sodick cuts through the lot, wire finishing the entire face in one set-up. In fact, using the rotary axis allows us to hit more faces in one go, preventing inaccuracy through resetting. Prior to installing the Sodick machine, this work required several set-ups per assembly.”

Quality is clearly paramount at this forward-thinking engineering business, where tolerances are typically in the realm of 20-25µm. The company is accredited to AS9100 and ISO9001:2008, as well as the ISO14001:2004 environmental management standard. Other sectors served by the business include aerospace, motorsport, medical, personal care and food.

“We sell on quality,” states Mr Gleeson. “For us, investing in the Sodick machine was not about saving time, it was about making parts right first time, every time. However, not only have we further improved our quality, accuracy and repeatability, the rotary axis in particular means we now look at components in a different way.

“This has increased our capability and reduced set-ups. In addition, the machine has allowed us to introduce unmanned operations overnight, which is hugely beneficial. We will certainly look at Sodick again when our other two wire EDMs approach the end of their working life.”

Source: Pesmedia