Variable shaft sizing for measurement targets

An apparatus for measuring a hole in a part, the hole characterized by a central axis, the apparatus having a pressurized and a nonpressurized configuration, the apparatus comprising:

• a body, the body comprising a channel;
• an expandable shaft extending from the body, the expandable shaft expands along a centerline of the shaft, the expandable shaft comprising a vessel with a channel and a fluid located within the channel in the vessel;
• the vessel fitting within the hole of the part in the nonpressurized configuration and the vessel expanding to contact the hole in the pressurized configuration;
• a pressurization system that pressurizes the fluid within the channel so as to cause the vessel to expand to the pressurized configuration, the pressurization system further comprising;
• a screw extending into the channel;
• a plunger located in the channel;
• and
• a ball bearing located in the channel between the screw and the plunger, the screw, plunger, and ball bearing configured such that manipulation of the screw biases the plunger so as to place the fluid under pressure;
• and
• the vessel in the pressurized configuration is expanded such that the centerline of the vessel is substantially aligned with the central axis of the hole.