31. Next drill pilot holes , at least 10 inches apart, along the outer edge of the casing. 32. Drill pilot holes , and replace the screws. 33. Be sure to drill pilot holes first. 34. Finally drill a pilot hole { inch from each end directly through the top of the casing. 35. Glue the plug in place; allow time for the glue to set, then drill a pilot hole . 36. The massive cutters are pulled up as they grind through thick rock, boring along the pilot hole . 37. The appropriate pilot hole will prevent binding while providing sufficient friction to keep the screw from loosening. 38. If you use wood screws, drill pilot holes first, then counterbore larger holes to recess the screwheads. 39. The other hand positions the screw in the pilot hole until the screw bites into the work. 40. Fill the plug hole with a wooden dowel, drill a pilot hole and drive a new screw.
