To provide more flexible and reliable CNC machines, Central CNC Machinery Ltd had to reassess machine design and its existing component suppliers. The key facilitating factor was THK’s Caged Ball™ technology and LM guides.

Central CNC Machinery Ltd not only manufactures its own computer numerically controlled (CNC) machines, it also uses them to produce component parts and to provide a contract CNC machining service. The company’s director, Stuart Merewood, says the contract service means that Central CNC Machinery Ltd is an end user of its own machines. “Because we provide an in-house CNC service, and use the machines to make parts, we demand the same standards as our customers. In fact, because it’s our machines and the service we offer can lead to new sales, we need to be sure that the end result is of the highest quality.”

Stuart explains that the Yorkshire-based firm supplies its CNC machines to a variety of users including exhibition contractors, shop fitters, sign makers, woodworking firms and furniture manufactures. He says this is made possible due to the machines’ flexibility. “The CNC1400D range is extremely versatile and is used from one end of the scale to the other – from the guy who has a machine in his garage to multinational companies.” This flexibility, he says, is derived from the unique design of the CNC1400D range, which incorporates an usually large machining area.

The machines’ solid construction also makes them ideal for heavy-duty production applications. “Our customers,” Stuart explains, “use a variety of materials including non-ferrous metals, plastics and woods, consequently the machines have to contend with fairly extreme environments. That’s where THK’s Caged Ball™ technology comes in.”

Stuart explains that since the launch of its first CNC machine in 1999, Central CNC Machinery Ltd has used THK’s patented Caged Ball technology to provide virtually maintenance-free, smooth and silent linear movement. Manufacturing around 30 machines a year, Stuart says the company’s use of THK’s LM guides has been a huge success, resulting in improved machine reliability.

“The LM Guides are vital to our machines. If they fail, the resulting downtime could be very costly,” Stuart explains. “So when we were deciding on our guide supplier, we realised that we had to get the best, and THK had the best product on the market.”

“Our machines are usually installed in dusty, harsh environments that can be extremely abrasive. We have found that THK’s LM guides tend to stay cleaner for longer, making our machines more reliable.”

Stuart goes on to say that THK’s LM guides also provide an extremely smooth movement which means Central CNC Machinery Ltd’s machines produce a higher-quality finish, which is especially important in plastics. “A smooth movement is extremely important because without it you wouldn’t be able get a good finish. This is especially true with the machining of acrylics or plastics where machine movement can be very evident.”

Moreover, since Central CNC Machinery Ltd uses its own machines to provide both a CNC machining and component manufacturing facilities, accuracy is crucial. “Without high accuracy levels, we can’t build the machines to the high standards demanded by our customers. Therefore, the accuracy of the CNC1400D range is not just a selling point to us, it’s also a production issue.”

Stuart says that after nearly five years of commercial success, Central CNC Machinery Ltd – a subsidiary of Central Woodworking Machinery Ltd - is ready to introduce new features including a fully-automatic tool-changing facility and three-spindle machine. Stuart admits that the developments will place greater pressures on the CNC machines but is confident the component parts, including THK’s LM guides, will be up to the job.

“The Caged ball technology has provided us with improved finishing and greater machine reliability. I see no reason to suspect that it will be unable to cope with stresses and strains presented by these new initiatives.”

THE THK LM guides used by CNC Machinery Ltd are SHS25C2SSC1+400L, 1950L and 3000L.