Profile: Par Manufacturing Inc. provides solutions for thread grinding needs. We specialize in internal and external thread grinding, tool room service as well as general machining. We provide external & internal threads of component parts for aircraft, defense and aerospace sectors. Our external thread grinding capabilities include up to 72" on centers, swing up to 22", 60" continuous lead and grind up to 12.375" OD. Our internal thread grinding capabilities include maximum bore ground 9.50", minimum bore ground .750", swing up to 12" and 44" maximum part length.