Quote Originally Posted by Rob T View Post
I am curious, as we have no "before" and "after", what would we expect the tolerance to be on a fabricated frame like this? What is our likely measurement error, even with the laser technique? This is a great technical challenge for a home shop and I am trying to learn....
The design document of an assembly like the frame has datum points like the centerline for reference.
Every data point is referenced to the datum and has a priority. Some are considered "critical" like suspension mounts. With cost and quality in mind, some tolerances like body mounts, are loose. Critical data points are identified on the document for "quality control" to pay particular attention too. If that happens..... I would consider plus or minus 0.020 for the mounts in question here but only FFR knows.
jim