A mainstay in most machine shops, the belt grinder assists in greatly increasing the speed at which parts can be ground down in a safer, more controlled manner compared to an angle grinder. As an effort to build a tool like this one for the first time, Julien Alexandre chose to use the Arduino Opta as its controller while designing it from the ground up.

Belt grinders, as the name implies, use a rapidly moving, abrasive belt that has been wound around a set of pulleys and gets driven by a large motor. The main drive pulley was mounted at the rear of the machine and securely connected to a three-phase AC motor. Above it is a height-adjustable point for controlling the belt’s tension, which also aids in swapping belts when needed. The last two pulleys are situated across from the motor and can be tilted vertically to alter the grinding angle. Lastly, the entire assembly can pivot to lay flat on the table or raised at an angle to it.

Facilitating the belt grinder’s operation is an Arduino Opta micro PLC. It receives a signal from two digital inputs that, when either is active, cause the Opta to blink a blue LED indicating to the operator that an error occurred in the security relay that manages the safety chain.. The motor controller (a variable-frequency drive) receives its values from a switch and a potentiometer located on the control panel, with the former dictating if the system is active and the latter being used for adjusting the speed. To see more about Alexandre’s ongoing projects, you can visit his Instagram page here.