Sometimes, the bolt holes or bolt surfaces may be machined uneven. Bolt holes in locations 1 through 4 shown in Fig. 6.18 may be uneven. Such uneven surfaces in both holes and bolts could lead to loose bolting and misalignment. Sometimes, uneven holes could produce “ovality” or non-circular holes. If ovality was measured, recommendation is to clean up bolt holes to circular shape. Uneven bolt sizes lead to shearing of bolts and eventual misalignment