Template bushing and locking means

Claim 1

In combination, a thin plate member or jig and a lockable drill bushing means comprising: a thin plate member having upper and lower parallel surfaces with aperture means extending from said upper to said lower surfaces for retaining a removable bushing therebetween, said aperture means having upper and lower perimeters which are flush with the respective upper and lower plate surfaces; reuseable bushing means removably disposed within said aperture means including an elongated body of predetermined length, one end of said body being enlarged for preventing said end from passing from the lower surface of said plate member to the upper surface of said plate member, said body being formed with external left-hand threads adjacent the free end of said body for receiving locking means thereon and an inner bore for guiding a drill through said body and underlying plate member, said body projecting substantially outwardly from said upper surface relative to the overall length of said body, said reuseable bushing means having means provided on its external surface at the lower portion thereof for frictional engagement with said thin plate member; and reuseable locking means with internal threads cooperatively removably engageable with said left-hand external threads on said bushing body for securely positioning said bushing against said thin plate member, said locking means being tightened by the rotational movement of a drill as it is guided within said bushing means.