I have a pipe of unknown inner diameter. The pipe is big so I cannot measure it's outer diameter (the outside jaws won't reach the midpoint). I want to measure inner diameter.
That should be easy, in theory, using the inside jaws. But how to ensure I am measuring diameter and not some other distance within the circle? I can try to forcefully expand the jaws, but that's not precise. I need to be very precise - I need to fit 3D print into the pipe exactly.