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Executive Report: Height of performance Phil Mist puts to the test an innovative laser-welded diamond blade that has just been launched by the specialist supplier, DTAS. In the early days of diamond blades, users had to choose between either a sintered or a laser welded product, and then selected a version depending on the application. This could be somewhat arbitrary with, for instance, some blades that were designated as suitable for cutting concrete being identical to general-purpose ones. Today, however, there is far greater choice, which can be rather bewildering. Finding the best value for money for a given application often boils down to trial and error. Recently some manufacturers have introduced blades with novel features such as incorporating holes in the actual metal blade core. The height of usable segment has gradually increased from 5mm to 15mm on some blades, with most laser welded products having an area of freeback (a diamond-free zone) for welding into position. Manufacturers have competed by announcing larger and larger segments with more and more usable diamond. Usually, the highest or largest segments are manufactured to be especially free-cutting, but also may wear more quickly. DTAS has just launched a blade with 20mm-high segments. The technology incorporated in the Duro Ultra Shoxx is said to have taken six years to develop, with origins in the automotive industry. The segments are manufactured using a thermo-electric process, rather than the more traditional sintering, before being laser welded to a low-carbon steel core. DTAS claims this gives a higher density segment that cuts virtually all common construction materials, hard or soft, with 20-30% longer life. Currently available in 230mm, 300mm and 350mm sizes, Shoxx blades have a distinctive logo stamped into one of the segments. I tested a 300mm-diameter version, which I fitted to a Makita 300mm disc cutter for use on many standard construction materials, including several types of red bricks, various cement blocks, block paviors, a concrete paving slab, a concrete lintel, hard solid blue bricks, and a very hard padstone. Extremely thin segments The segments appeared somewhat softer than some others and provided a very aggressive cut when used on both hard and soft materials. DTAS claims a 20% improvement in the speed of cut, and I would not argue too much against this. The rate of cut was achieved despite the sample blade being marked as suitable for use at an edge speed of 100m/s, whilst the disc cutter rotated at only 80m/s, resulting in a loss of 20% of edge speed. In theory, this should slow the rate of cut, but the Shoxx blade still performed impressively. Some of its speed is achieved because the segments are extremely thin, being nominally marked 1/8in thick, which should be 3.2mm, but my measurements recorded 2.8mm. In the past, some users have been concerned that thinness could lead to greater segmental loss and excessive wear. DTAS claims that, in side loading tests, the Shoxx blade achieved a rating of 1000N/m2, comparing favourably with the 600N/m2 typical of many other products. Side loading is a critical factor for all diamond blades, but especially if very high diamond segments are used, since it is easier to twist a blade and snap off segments. The Shoxx blade is said to meet all European safety standards. It is free cutting and, despite sustained, heavy pressure being applied on all materials, there appeared to be no overheating and no increase in vibration emissions (tests at OPERC gave a figure of 3.9m/s2 with the Shoxx fitted to a Stihl TS400.) Particularly satisfying was the fact that the segments did not lose their cutting efficiency and I never had to open them up by running the blade over an abrasive cement block. In addition, the blade coped well cutting softer, more abrasive materials. Overall, performance was very smooth, and the Shoxx blade is a high-specification product that is fast cutting, gives low vibration, looks good and generally performs well, even under extreme duress. • T
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552470 Executive Hire News › Archives › September 2007 › Executive Report › Height of performance
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