Like any fledgling company, the winds of change can blow quickly through a business, and this was certainly the case for Shropshire Precision Engineering (SPE). Initially set up as a ‘part-time’ business, it wasn’t until technical director Robin Chisnall joined the Shrewsbury-based business in 2017 that the company set about upgrading its machine tool and cutting tool technology – with XYZ Machine Tools and Industrial Tooling Corporation (ITC) proving the partners of choice.
As an engineer who has been in the industry for almost 50 years, Chisnall sold his previous business for a life of happy retirement back in 2016, but when he got the call from fellow director and company founder Chris Mills only a year later, his love for the industry was too great a pull.
The company’s three-axis machining centre and teach lathes were quickly replaced by an XYZ TC65LTY turning centre with live tooling, a four-axis XYZ machining centre and an XYZ ProTurn 425. The arrival of these machines reduced set-ups and improved throughput, so the company followed up by investing more recently in an XYZ UMC 600 five-axis machining centre and a fourth-axis 1100HD machine. While this investment has improved productivity and throughput, it is the reliance upon cutting tools from ITC that is delivering production consistency, impeccable surface finishes, and reduced waste and costs while making a major contribution to productivity improvements.
When the ISO9001-certified business launched in 2014, the workload primarily centred around the automotive industry. As a subcontract manufacturer, SPE still produces components for automotive customers as well as those in a host of other sectors. However, nowadays 90% of the workload focuses on serving the rapidly growing and high-demand semiconductor industry.
The company provides a complete manufacturing, cleaning, assembly and packaging service, as well as testing and production control. Much of the growth in the semiconductor market is credit to John Bradley joining the company as general manager and directing the business toward this growth sector. Lead times, precision, component consistency and quality are essential in the semiconductor arena, which is why Chisnall turned to ITC.
“When I joined the company, it was primarily using cutting tools from distribution companies,” he explains. “The issue was a several-day lead time for certain standard tools with no guaranteed delivery date. We often had to take jobs off machines because we didn’t have the tools. Furthermore, a repeat order for an end mill would sometimes see us receive a different brand, coating or geometry, completely ruining our performance and efficiency.”
He adds: “I had worked with ITC in the past and knew that their service, support and delivery times were second to none. They are also a UK manufacturer that can produce special tools as well as standard products. I called the ITC representative and we set about standardising our tool library and consumption.”
A lot of components that SPE machines are small, delicate stainless steel and Inconel parts. To machine these, SPE implements ITCs 5021 series of long-length, centre-cutting five-flute end mills with harmonic fluting and the 5041 series of five-flute extended-reach end mills.
“Instead of changing between roughing and finishing tools, we trochoidal mill with ITC five-flute Cupro-coated tools at high speeds and feeds with a low depth of cut,” says Chisnall. “The surface finishes are incredible and the tool life is 50% better than any tools we have used before. In fact, we’ve recently started three new machinists and they are all struggling to comprehend the remarkable tool life we get from the ITC end mills and the reduction in tool changeovers.”
The tool life is a huge benefit to SPE, as are the improved surface finishes. Before the company started using ITC tools, surface finishes were inconsistent and there was a requirement to undertake significant hand polishing. This is no longer the case, saving SPE a lot of labour hours every week.
From a productivity perspective, the range of ITC trochoidal five-flute end mills and the 2152 series of two-flute ball nose end mills (used from 1 to 8 mm diameter for steel machining) improved throughput significantly.
“All of our jobs are small volumes, so we can’t always track cycle times,” says Chisnall. “However, when we first changed our cutting tool supplier there were several jobs with 20 or 30-minute cycles that reduced to less than 10 minutes with ITC tools. This is a credit to the quality, performance and rigidity of these tools, which enable us to run 30 to 40% faster than cutters from other suppliers.”
As well as using a complete array of ITC’s UK-manufactured cutting tools, which range from end mills and drills through to taps and reamers, the manufacturer has also invested in Big Kaiser tool holders from ITC.
“When we moved to ITC we could conduct trochoidal milling at much higher feeds and speeds,” explains Chisnall. “However, the increased cutting forces were pulling tools from our milling chucks. To retain and extend these productivity gains, we needed high-quality chucks. We spoke with the ITC engineer and we bought the Big Kaiser Hi-Power BBT milling chuck with dual face and taper contact. The slim-line design gave us the reach we needed, while the clamping forces eliminated tool ‘pull-out’. Additionally, the Big Kaiser chucks improved our rigidity and stability, allowing us to run ITC tools at even higher speed and feed rates.”
According to ITC, the dual face and taper contact system on the Big Kaiser milling chucks from ITC goes way beyond maximising performance and creating process security for high-speed and feed applications. Surface finishes and precision also see improvement.
“We have a lot of tight-tolerance work and one job requires a series of 6 mm diameter reamed holes at a 70 mm pitch,” says Chisnall. “We would have to do test runs on parts like this to avoid scrap. Such a deviation was not down to the machine or process reliability – but the tool holders.”
To eradicate the issue, ITC suggested SPE try the Big Kaiser Mega New Baby Chuck for drilling and reaming the holes. The company trialled a reamer with the Mega New Baby Chuck and it was reaming to a concentricity and precision level within 3 µm. The runout of the previous chucks would never have held such tight tolerances, reports SPE.
Concluding on the overall service from ITC, Chisnall says: “We have guaranteed next-day delivery on standard products, excellent technical support and an unfathomable diversity of special products. In fact, with every special tool, ITC will create a product code. This means we can order the specific code and get repeat orders of our special tools that are all manufactured in the UK. This consistency is of critical importance. Some of our parts have a value that exceeds £12,000. To scrap one of these parts because of tool ‘pull-out’ or the run-out on a precision feature is outside tolerance due to an inferior collet, is not acceptable for our business. That’s why we have chosen ITC as our cutting tool partner.”
For further information www.itc-ltd.co.uk