Kerf Gets Subcontractor into Top Gear

Ten years ago, Hopwood Gear Ltd invested in an Oxy-Propane gas cutting machine from Kerf Developments. Owning a machine that run like a dream with exemplary service support for over a decade was two of the key reasons why the Oldham based subcontractor went back to Kerf for its latest machine, a twin-head waterjet machine.

Founded in 1974, Hopwood Gear immediately set its stall out as a subcontract manufacturer with a niche for producing gears, gear sets and all associated components. Now with 40 years of gear manufacturing under its belt, Hopwood Gear is a true specialist, manufacturing gears from 4mm diameter up to 3m - and everything in between. The 33 employee company serves the defence, aerospace, automotive, white goods and consumer markets with bespoke gears for anything from a tank or submarine through to the everyday watch or washing machine.

To manufacture its gears and meet the demands of its wider subcontract business, Hopwood has a machine shop stacked with CNC EDM, turning and machining centres from Agie, Haas, DMG and Mazak as well as a multitude of specialised gear production machines. However, the issue for Hopwood was the upstream issue of profiling its gears and the consequent subcontract costs and lead-times. Discussing the issue, Hopwood Gear Managing Director, Mr Cory Hopwood says: "Ten years ago we were either buying steel plates for £500, or to save time we were paying upward of £1000 for the plates to be pre-cut into blanks. We invested in a twin-head Kerf Scorpion gas cutting machine to cut the cost and gain control over the process."

The 4m by 2m machine immediately cut costs by 50% when processing steel plates up to 150mm thick. Additionally, the Scorpion cutting head allowed the Manchester company to 'semi-finish' large gears with its impressive precision levels. Still in operation after a decade, the Scorpion is still well used today. Nowadays, the company has a need for a more flexible machine for processing a wider range of materials at even greater precision levels - enter the Kerf Optima 420 waterjet machine.

Kerf Cuts Through Customer Issues With New Waterjet.

The evolving face of gear manufacture now sees Hopwood Gear producing more gears up to 50mm thick from materials such as aluminium, titanium, plastic, stainless and mild steels. For profiling these gears, Hopwood was using a subcontract profiling company at a cost of up to £5000 each month. Commenting on this, Mr Hopwood continues: "We were spending a lot of money getting gear profiles cut prior to entering our machine shop for secondary processing.

However, the quality of gears was indifferent.

The supply was regularly outside our tolerance band and the gears were often tapered where the waterjet wasn't cutting at 90 degrees. As soon as we heard Kerf had a waterjet machine, we spoke to Dan at Kerf and gave him some of our externally processed gear profiles. Dan was confident the cut quality and precision of the Kerf Optima would solve all our issues. We trust Kerf implicitly, so we bought the Optima 420 waterjet machine. We haven't looked back since."

Kerf Unlocks Productivity for Hopwood Gear.

By installing the Kerf Optima 420, Hopwood Gear immediately improved the precision of its profiles, attaining a precision level of +/-0.05mm as opposed to +/-0.3mm on subcontract supplied profiles. This precision is credit to the highly acclaimed BFT high pressure pump on the Optima 420. The enhanced precision reduced returns and it also cut the internal re-working of gears. These factors reduced lead-times, improved precision and edge finishes and also prevented labour and machine time from being unnecessarily absorbed in the machine shop.

From an economic standpoint, Hopwood Gear estimates that £2000 of the £5000 monthly cost of profile cutting was actually material cost. So, by purchasing the Kerf Optima and acquiring the material direct from the stockholder, Hopwood Gear has reduced its subcontract costs by £3000 each month. The flexibility of the waterjet means that Hopwood has also eliminated an additional £500 per month in subcontract costs for laser cutting of thin plates and discs. With the easy-to-use IGEMS CAD/CAM system on the Optima machine, Hopwood's staff were comprehensively trained on the machine in one-day. The unparalleled ease-of-use and the automated running of the machine allows one operator to simultaneously run a number of machines, avoiding the cost of additional staff. Furthermore, the twin-head configuration permits fast dual-cutting production. This is ideal for a company producing anything from one-off and batch work in the region 50 through to production runs up to 200,000 off.

Far Reaching Benefits of Kerf Waterjet.

Whilst the Kerf Optima 420 waterjet machine has cut costs, improved quality and precision for the subcontractor, the benefits reach much further. As Mr Hopwood concludes: "The lead-time for external waterjet profiles was 4-6 weeks, now we can get the material next day and often turn work around in less than a week. By eliminating the 4-6 week supply chain, we can get gears into the machine shop for secondary machining a lot faster. This gives us more production capacity, better scheduling and it means our machine shop is always busy, as nobody is waiting on a third-party to deliver profiles to the machine shop."

"Furthermore, the profiles are more precise and this means fewer set-ups and operations in the machine shop. With fewer down-stream operations, there is more machine and labour capacity and even our cutting tool consumption has been reduced. To put it simply, our entire production facility would struggle to keep up with demand if we didn't have the Kerf Optima on the shop-floor."

Optima 4020 - April 2020

About Kerf

Founded in 2001, Kerf Developments have grown over the years to become the leading supplier of profile cutting machines in the UK and Ireland.

The company was originally formed to provide a repair and support service for customers operating a range of profile cutting machines. These machines were varied in size and capabilities. From small magic-eye gas cutting machines through to automated plasma and high pressure waterjet cutting solutions.

As the company’s reputation for repairing and in some cases upgrading older machinery spread – predominantly through word of mouth, additional engineers were employed to provide additional cover for the UK and Ireland. 

It was a chance request from a customer who stated that his older machine had reached the end of its life and needed replacing that journeyed the Kerf team towards machine development. The customer asked Kerf and it’s engineers to design and build a new machine using their considerable experience of what were the “best” products available.

The first machine was built using a rail based design which helped to isolate delicate electronic systems from shock loading, particularly when loading and unloading large steel plates from the machine. The control system selected was from Burny which has proven itself to be very reliable in challenging industrial applications across the world.

Heavy duty downdraft cutting tables were selected and the plasma unit was a high definition system supplied by Hypertherm.

After the installation, news of the productivity and reliability that the new machine provided along with the quality and accuracy of the parts being cut spread, and further orders for similar machines came flooding in.

The simplistic design and choice of best in class products are still in use today with new machines utilising the current Burny control systems, INOVA electronic torch height controls, and with the latest best in class UltraSharp plasma systems supplied by Lincoln Electric.

The success of the company has been based on providing quality products at competitive prices and backing the equipment up with effective customer service and support be it for oxy-fuel, plasma or waterjet cutting technology.

Kerf Logo Image