Final answer:
The three ways to establish a datum axis for runout specification are Axis, Hole, and Surface. These references ensure parts are measured consistently, allowing for precise geometric control in engineering designs.
Step-by-step explanation:
The three ways to establish a datum axis for a runout specification are Axis, Hole, Surface. The datum axis is an important part of geometric dimensioning and tolerancing, which allows for the specification of the geometry and orientation of parts in engineering designs. The datum axis can be defined based on a physically existing feature or a theoretical exact dimension.
An Axis is often established by a shaft or cylindrical feature, around which the runout is to be measured. The hole serves as a reference point for the inside features of a part, like the bore of a cylindrical part. Lastly, a surface can act as a datum when it's a flat plane from which the runout is measured. These references ensure that parts are measured consistently in relation to fixed points or axes.