Machining fixtures

A fixture attachable to the table of a machine for holding a workpiece in operative relationship with a tool of the machine, said fixture comprising:

• a base plate and means for locating said base plate in predetermined relation and in nonrotatable fashion on the table of said machine and for holding a surface of said base plate against an outer surface of said table,
• a plurality of locator blocks mounted on the opposite surface of said base plate and adjustable therealong toward and away from a center point on said base plate, each of said locator blocks having an abutment extending outwardly therefrom,
• means for holding said locator blocks in a selected adjusted position wherein the abutments of the same engage spaced parts of a peripheral surface of said workpiece to locate the latter and hold it against shifting laterally along said opposite surface of said base plate, and
• said holding means including apertures in said base plate opposite surface and arranged in sets, each set including a tapped and untapped aperture, and said holding means further including a dowel pin on each locator block seatable within an untapped aperture and a hole in each locator block to pass a machine screw which threads into a tapped aperture to hold the locator block to said base plate, and
• clamp means mounted on said base plate for adjustment to various positions thereon in accordance with the size of a particular workpiece located by said abutments, said clamp means engaging said workpiece and holding it against axial separation from said base plate.