Abstract: A method of achieving interchangeability of tool inserts in a quick release chuck mechanism mounted on a drive spindle, the chuck mechanism having a body member with an axial bore extending therethrough, and an end surface transverse to the bore, the tool inert having an end portion insertable in the axial bore, an axial opening in the insert for receiving the tool, and an adjusting screw in the axial opening for adjusting the tool relative to the insert, the tool insert further having an opposite end portion provided with a shoulder facing the end surface and engageable therewith; adjusting means on the end surface of the body member for axial movement for axially varying the position of the end surface relative to the shoulder for achieving a predetermined end surface position; and means for releasably holding the tool insert in the body member with the shoulder in engagement with the end surface adjusting means; the method comprising the steps of adjusting the adjusting means on the end surface of the body

Abstract: An improved quick release chuck mechanism is disclosed mountable on a spindle for releasably holding a tool or the like. The chuck mechanism comprises a body member having an end surface. A tool insert having a shoulder is supported by the body member. The end surface is provided with an adjustment for varying the position of the end surface for achieving a predetermined end surface position while mounted on the spindle. The tool insert is releasably held in the body member by an improved locking mechanism that positively forces the shoulder into engagement with the end surface. The improved chuck mechanisms, when mounted on multiple head spindles, provide a method for compensating for tolerance differences that exist between the spindles to achieve identical predetermined end surface positions for the spindles.