An electrospindle device includes at least one electrospindle extending about a vertical axis, the electrospindle including a motor, a shaft that rotates for transmitting motion, and an engagement portion for a toolholder in which a tool rotatably actuated by the shaft is mounted, the tool being actuated directly by the shaft; at least one toolholder support element including at least two toolholders; and at least one device for rotating the at least one toolholder support element, wherein operation of the at least one device for rotating the at least one toolholder support element brings a selected one of said at least two toolholders into vertical alignment with the engagement portion and extending in the vertical axis.

A fixturing device for attaching attached to a work piece and methods of attaching the fixturing device to the work piece. The device may include a body, a base, and an extension. The extension may extend outward from the body and is sized to initially be positioned within an opening in the work piece. The extension may be expandable in size to engage with a backside of the work piece at the opening to secure the device to the work piece. The device further includes an interface for receiving to a tool that performs an operation on the work piece.

A fixturing device for attaching attached to a work piece and methods of attaching the fixturing device to the work piece. The device may include a body, a base, and an extension. The extension may extend outward from the body and is sized to initially be positioned within an opening in the work piece. The extension may be expandable in size to engage with a backside of the work piece at the opening to secure the device to the work piece. The device further includes an interface for receiving to a tool that performs an operation on the work piece.

A milling apparatus has a housing, a drive shaft extending along and rotatable about an axis in the housing and an axially compressible and radially expansible washer stack on the front end of the drive shaft. A tool is held by the on the shaft. A bolt projects radially in a slot through the shaft and is limitedly axially displaceable in the shaft. An actuator element shiftable axially in the passage projects axially forward out of the drive shaft and is fixed in the bolt. A clamping assembly axially compresses and radially expands the stack so as to lock the tool to the drive shaft. A spring assembly is braced axially forward against the housing and axially rearward against the bolt. A piston axially displaceable on the drive shaft in the housing bears axially forward on the bolt.

A milling apparatus has a housing, a drive shaft extending along and rotatable about an axis in the housing and an axially compressible and radially expansible washer stack on the front end of the drive shaft. A tool is held by the on the shaft. A bolt projects radially in a slot through the shaft and is limitedly axially displaceable in the shaft. An actuator element shiftable axially in the passage projects axially forward out of the drive shaft and is fixed in the bolt. A clamping assembly axially compresses and radially expands the stack so as to lock the tool to the drive shaft. A spring assembly is braced axially forward against the housing and axially rearward against the bolt. A piston axially displaceable on the drive shaft in the housing bears axially forward on the bolt.

A fixturing device for attaching attached to a work piece and methods of attaching the fixturing device to the work piece. The device may include a body, a base, and an extension. The extension may extend outward from the body and is sized to initially be positioned within an opening in the work piece. The extension may be expandable in size to engage with a backside of the work piece at the opening to secure the device to the work piece. The device further includes an interface for receiving to a tool that performs an operation on the work piece.

A fixturing device for attaching attached to a work piece and methods of attaching the fixturing device to the work piece. The device may include a body, a base, and an extension. The extension may extend outward from the body and is sized to initially be positioned within an opening in the work piece. The extension may be expandable in size to engage with a backside of the work piece at the opening to secure the device to the work piece. The device further includes an interface for receiving to a tool that performs an operation on the work piece.