How to Use Diamond Blades Safely: Cutting Techniques, Blade Types & Best Practice
Circular blades containing diamond segments are widely available in standard sizes, ranging from 100mm to 300mm for use on landscaping and paving projects, mainly to cut paving slabs and blocks. Every type of material should be cut using a specific type of blade, although some are sold as ‘universal’. Essentially though, it is preferable to choose the right blade for the material to be cut, as using the wrong blade can result in poor cutting or risk damage to the disc, and possibly, the machine.
Usually constructed using manufactured or man-made synthetic ‘industrial’ diamonds, fused into a metal matrix that is commonly known as the ‘bond’, the diamonds are graded into sizes to suit the material to be sawn. The shape and hardness of the diamonds will be graded and their uses shown on the packaging.
Each blade will have a ‘use-by’ date stamped somewhere in the text, as the metal matrix may begin to decay after a period of time, and become weakened and its use may become dangerous, causing debonding or fracturing during use.
The ‘bond’ is constructed using a blend of metals including cobalt, nickel, and tungsten with diamonds introduced to suit the material to be sawn, with the ratios varying for each. As the diamond blade wears away, it constantly reveals more diamonds, to maintain a cutting edge.
Maintenance of the disc is of paramount importance for safety and to ensure accurate cutting. Dumping the machine and blade into the back of the van should be avoided, as they can easily become warped and damaged. Specially designed sharpening blocks are available to maintain the efficacy of the blade. The use of water when cutting will extend the life of the blade, as well as suppress dust, by keeping the blade cool during working operations. These cleaning blocks should not be over-used as they will wear away the blade.
Hard materials such as granite and porcelain require a softer bond, whilst softer materials such as asphalt and concrete will require a harder bond, which may sound perverse! As a general rule, softer bonds cut faster and have a shorter life span than when compared with harder bonds, as the cutter will likely be on full-trigger revolution mode.
Accessories such as hand-held polishing pads are an effective way of finished cuts, removing any micro-chips or flaws leaving a smooth finish on natural stone. These may take the form of polishing pads held into position with Velcro backing, with different grades of grit to polish cuts either wet or dry.
Specialist vacuum brazed diamond drill bits and core bits are available for pre-drilling difficult corners, both internal and external, to relieve tension before cutting. They are also available as core drill bits to allow circular cuts to be made accurately and seamlessly.
