Powder deposition by laser is setting new standards in knife blade technology at Stanley, where sharper for longer is the new mantra.
Running unmanned and continuously for three days, the application at Stanley Black & Decker is now the longest, uninterrupted, single-run laser deposition process in the world. But as amazing as this may seem, it’s little more than a first step for this progressive manufacturing company. The Stanley brand is synonymous with workplace utility knives. Professional plasterers, carpet fitters and decorators at construction sites around the world have used Stanley knives throughout their careers. Add to this multiple applications in markets such as packaging and handicraft, and few will have escaped exposure to this iconic product. The blade itself is remarkably simple, selling in two major formats: trapezoid blades preferred by UK and US customers; and snap-off segmental blades for European markets. Both are housed in Stanley’s instantly recognisable yellow and black retractable-blade handles. In fact, so distinguished is the brand that evolution and new development is no mean feat, but this is the challenge being met head-on by R & D staff at Stanley Black & Decker, as the company is today known following a merger in 2010.
An edge of dust
“Carbide” is the next generation of Stanley knife blade. The fusion of product innovation, process technology, and marketing skill is about to take utility knife operations to a whole new level. And at its core is a high-performance TRUMPF laser solution depositing a carbide powder to the blade edge. The first sales and marketing giveaways of Carbide have already taken place following a series of recent “soft launches” around the world. “The soft launches are deliberate to test the market: too much, too quickly will leave us unable to meet demand at this stage,” says R & D Manager, Peter Culf. This revolutionary technology was developed and installed at the Stanley Black & Decker UK facility near Sheffield, and adds to existing “conventional” knife blade manufacturing capacity.
At present, Carbide blades are manufactured using six inline, purpose-built application centers. Essentially these house TRUMPF laser deposition head and camera systems with coiled strips of blades fed automatically below the nozzle. TRUMPF TruDisk technology provides the laser source, while TRUMPF TruMark laser marking stations are integrated into each center. The blades are subsequently ground in a separate operation to produce the required edge angles. Stanley Black & Decker’s application centers deposit a carbide powder on the cutting edge of each blade. The result is knife blade technology redefined. “Our alliance with TRUMPF came about because they are clearly the market leader at the premium end of the laser market,” says Culf. “If we didn’t have TRUMPF on board, our precision deposition process wouldn’t have got off the ground.” This is a process that boosts hardness from 800 Vickers Hardness for a standard blade, to 1200 Vickers Hardness. “Using an industry standard CATRA testing machine, Carbide blades show up as virtually indestructible,” says Culf.
Surprisingly, this caused something of a dilemma for the marketing department. “Our market research showed that claims of any blade offering 10 or 12 times the life of our standard blades would not be believed,” he states. “However, because of Stanley’s reputation, five times greater life was deemed conceivable. As a result, this is what our marketing materials reflect despite the reality that life expectancy is far, far greater.” Working hand-in-hand with marketing has been a prevalent theme throughout the project. The Stanley Black & Decker marketing team was insistent on a product that “looked different” in the marketplace. The special look of the black edge created by the laser deposition process was just what marketing needed, and even though it could be removed by introducing more argon shielding gas, it was decided to retain this “black and hard as the devil” look, and even enhance it by laser marking the Carbide brand in stylish black lettering along the side of each blade.
The project demonstrates that laser deposition technology is not the sole reserve of high value parts produced in low volume, such as jet engine turbine blades for example, but can be applied to simple products manufactured for mass markets. “We are no different than any manufacturing company. Each expenditure has to be meticulously justified, but our driving motivation was that we wanted a superior blade,” explains Culf. “Advanced technology of this type obviously carries a cost, but we believe that our customers will readily appreciate the performance benefits that result. According to our market research, life is the leading customer requirement, followed by first-cut sharpness, price, brand and safety. Ultimately Carbide is a prestige item that will become our ‘hero’ brand.” As demand ramps up, Culf says that installing more TRUMPF based application centers is very feasible. This move will of course help boost the company’s global capacity, but there is still ground to cover. With this in mind, don’t be surprised if Stanley Black & Decker make the process even sharper in the very near future.