Common gearboxes typically have two sets of gears: enter and output. the enter & the output. The enter gears are preset over the countershaft, making them solitary units. It drives the individual gears on the main shaft, which rotate freely over the bearings. Spur and helical gears are Utilized https://gearbox19630.mdkblog.com/39621479/the-2-minute-rule-for-gearbox