Use part geometry as datums
One of my biggest pet peeves is that the way Creo handles GD&T datums is flat out wrong. A datum referenced on a production print must refer to a physical feature of the part, so that someone inpsecting the part knows how to locate the part to inspect it. But Creo only lets you use axes or planes to define datums. These are "theoretical" features that don't actualy exist within the physical part. A planar datum is more of a trivial matter, as you can define a plane to be coincident to any flat surface, and just have to deal with the superfluous 0.00±0.01 dimension from the plane to the surface. But with an axis, it is another matter entirely. An axis datum must be a cylindrical surface. And on a part with multiple cylindrical surfaces all revolved about the same axis, it is wrong to simply define the axis as your datum. One of the surfaces must be the datum, and the remaining surfaces are inspected in reference to the datum. But there is no way to define which surface is the datum, as the datum is just an axis. This makes it impossible to properly assign GD&T to any part.
So my product idea is to allow datums to be used in GD&T callouts to be defined as the GD&T standards mandate they be called out. As planar or cylindrical surfaces of the solid model, and not planes and axes. Then provide for a means of clearly depicting on a drawing to what features those datums refer.
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