Around 30% of Claro Precision Engineering Ltd’s production is based on five-axis machining that is carried out on four of the company’s 19 CNC machining centres at its premises in North Yorkshire.

A current contract requires Claro to machine a trial ankle bearing featuring detailed contours from medical-grade plastic. Other products include instruments made from 17-4 ph stainless steel (these are used by surgeons carrying out hip replacements, to remove bone prior to the implant going in).

Claro also manufactures a sleeve in Ertacetal H; this accommodates a pig’s heart valve that is implanted into heart patients, giving a ‘live tissue’ solution rather than using a mechanical valve. Sales director Mike Lewis says the sleeve has to be of the highest precision and burr-free, as it stays inside the patient for the rest of their life.

Holding the ISO 13485 medical accreditation, Claro is a second-tier manufacturer and makes around 150 different types of medical components (this equates to thousands of individual parts a year). The company also makes a number of full assemblies comprising a series of items.

“We’ll assemble and laser-mark, then bag and label them, so our customer simply supplies the hospital with what we’ve produced, complete,” says Mr Lewis, adding that Edgecam CNC software (www.edgecam.com) is key to Claro’s ability to provide a fast, reliable and versatile service. “We’re taking on ever-more challenging jobs, but they rarely pose a problem to our engineering team. I look at these medical components and wonder how we would make these without Edgecam?”

He says the CAM software’s five-axis capabilities have allowed Claro to achieve success, particularly at the “trickier” end of machining; he also highlights the fact that a program can easily be edited not only for a different machine but also for a different cutting technology — a point echoed by Claro CAD/CAM engineer Dominic Watson.

The company has a number of three-, four- and five-axis machining centres — plus horizontal machining centres — from Matsuura, Doosan and Hardinge Bridgeport. Sometimes, the re-scheduling of work means an order that has been programmed for a Matsuura MX 520 five-axis machine needs moving, so the ability to ‘re-post’ it quickly and reliably to another machine is vital — as is the ability to transform the program from one technology to another.

Mr Watson says that machine availability has, on occasion, meant that having created a five-axis program for one-hit machining, he has needed to revert to pallet-based machining with a series of operations.

“Essentially, they are two different technologies, but I simply edited what I’d created in Edgecam as a five-axis program and prepared it for another machine without having to re-program it.

"We have also gone from a three-axis program — or one for a horizontal machine — to five-axis working. Being able to edit in this way has saved us hours of work when we’ve needed to switch machines.”

He adds that before Claro installed Edgecam about three years ago, machining involved a number of separate operations and considerable work at the machines. “Now we can have multiple components programmed complete on a tombstone fixture; and while we also get involved in designing products for some customers, most of our work comes in as an existing 3-D model.

"We will open it in Edgecam, then use the new Workflow interface; this automates many aspects of the setting-up process, including vices and material stock — and the tool store for the machining side.

“All our tools are set off-line, so when a job gets to the machine, it is ready to run. Special tooling, materials, paper-work, programs and set-up sheets are at the machine, ready to prove out the program that Edgecam has produced.”

The software’s collision detection capability is another important aspect for Claro. “It gives us complete confidence that the program will run reliably and accurately when we start cutting metal or plastic. Edgecam is now key to our manufacturing process, as we no longer need to create several programs and stitch them together.

"We can program parts complete, with no errors, right across our range of machines types and makes. We still do some three-axis milling, but mostly it’s five-axis machining with one datum and Edgecam taking care of the programming.”