Abstract: A system is provided for drilling through contiguous first and second plate members so as to avoid the formation of burrs at their interface. Using a jig, the plate members are held together at distant locations while assuming a desired mutual orientation in a longitudinally extending upright plane. Loosely suspended from a frame manually movable along the length of the jig, a horseshoe shaped yoke is positioned in a laterally extending upright plane and has a pair of depending legs straddling and adjacent to their associated plate members to be drilled. A hole finding pin on a first leg is manually inserted into a pilot bore provided in the first plate member. Thereupon, opposed clamps on the depending legs firmly engage the plate members in the region of the pilot bore. From the side of the second plate member, enlarged sized bores are drilled through the plate members axially aligned with the pilot bore.

Abstract: A system is provided for drilling through contiguous first and second plate members so as to avoid the formation of burrs at their interface. Using a jig, the plate members are held together at distant locations while assuming a desired mutual orientation in a longitudinally extending upright plane. Loosely suspended from a frame manually movable along the length of the jig, a horseshoe shaped yoke is positioned in a laterally extending upright plane and has a pair of depending legs straddling and adjacent to their associated plate members to be drilled. A hole finding pin on a first leg is manually inserted into a pilot bore provided in the first plate member. Thereupon, opposed clamps on the depending legs firmly engage the plate members in the region of the pilot bore. From the side of the second plate member, enlarged sized bores are drilled through the plate members axially aligned with the pilot bore.