I am working on a series of very small parts that need to be laser cut, then verifying dimensions with an image dimension measuring system (Keyence IM6000). The part has an inside radius dimension of 3.47 +/-0.1. My understanding of this tolerance is that as long as the surface in question lies within the cylindrical shell with interior radius 3.37 and exterior radius 3.57, it fits the tolerance. However, since this part is not a full circle, just an arc, that means that arcs with radii anywhere between 1.5444 and 7.1940 can fit in this region (they just wouldn't have the same center).
The Keyence system will recognize the edge and apply the best fit curve. So if I program it to find the arc that defines the edge and give me the radius, it could give me a radial dimension that is out of tolerance to a surface that is within tolerance.
Is my understanding of the tolerance on the drawing wrong or should it really be a roundness/circularity tolerance? The Keyence system has the ability to measure roundness as well, I just want to make sure that I am interpreting the tolerance correctly. I've attached the image below to illustrate what I'm talking about.