There are three ways of cutting with an angle grinder: straight, pendular, shuttle.
Each way has its application, advantages and disadvantages.
cutting is done in one pass with full blade penetration in the work piece. Suitable for cutting through, cutting sheet materials and short dead-end cuts. Provides better flatness and less roughness of the processed edge. The least efficient method, able to quickly deform the core of the blade.
cutting is done by alternately penetrating and withdrawing the blade form the work material, changing the “angle of attack”. Suitable for roughing cuts, for large volumes of work, as well as with the use of low-power machines. Especially, effective for cutting highly-reinforced concrete when passing steel bars. The most productive method because the efforts of the cutter can be added to the blade load. Provides intense cooling of the core. High roughness of the processed edge.
cutting is done by many sharp passes at a low penetration. Suitable for finishing cuts on difficult low-abrasive materials (granite). Productive method provides better linear cut. Gentle conditions for the core of the blade. Effective when using low-power machines. Strong self-grinding effect, reducing overall lifetime of the blade.