An employee and a coworker were assembling a manure agitator frame. They were using a rough-terrain forklift and nylon sling to support the weight of the right-side stabilizer wheel bracket while manually aligning and pinning alignment holes between the wheel bracket and mounting flanges on the frame. While walking around the stabilizer wheel bracket, the coworker bumped into the edge of the stabilizer wheel bracket. At that time, the bracket position shifted while the employee was using one of his left-hand fingers to feel the mounting hole alignment between the mounting flange and stabilizer wheel bracket. His fingertip was pinched in the shear point between the wheel bracket and mounting flange, resulting in surgical amputation at the first knuckle.