Employee(a) worked on 11/10 from 0730-1630hrs, after working EE's scheduled shift employee(a) was called back to work at 1900, 2218, 0134 and 0230hrs. On 11/11 around 0430hrs employee was replacing a gearbox with employee(b). While employee(a) was aligning bolts for installation, the gearbox slipped out of employee(b) hands and crushed the pinky finger of employee(a) right hand.