For resinoid bonded abrasive discs, the hex nut and washer system has proved to be superior to the weld nut and wire mesh system. The washer is a stronger mounting unit in that it distributes the pressures over a greater area and is located deeper into the back of the abrasive disc. Anchor adds strength to the system by embedding the insert in an extremely strong backing material.
The nut and washer system allows the abrasive to have fuller contact with the steel mounting plate and therefore allows less movement of the abrasive body under grinding pressures. With a more positive contact with the mounting plate there is a more aggressive abrasive action. Also with fuller contact between the abrasive body and the steel disc wheel, greater accuracy and reproducibility are maintained.
The weld nut and wire mesh system, however, does have an excellent place in one type of abrasive disc. It is used in the mounting system of Oxychloride Bonded Discs which are very brittle and need this added reinforcement of wire mesh.