Zero tolerance???? :wtf:
If you know anything about manufacturing, you would know that every process has a tolerance... It is impossible to manufacture parts to zero tolerance....
The head machining line that I worked on had a valve seat runout tolerance of .013 mm (13 microns) which is smaller than the diameter of a hair...
The frame tech guy could pull frames straight with his machine and was good at it... Like I said, if he couldn't pull it straight, it was too far damaged to be fixed... He's been in business for over 30 years and always has two weeks of work to do... He had the proper rack with frame pulling equipment to pull the frames and get them straight within tolerance...
Everything has a tolerance... The body section of an assembly plant builds to a tolerance of +/- 3 mm, it is literally impossible to build a body with zero tolerance... Assembly plants have dedicated fixtures and jigs specially made for each particular part to locate each body panel before welding them... Even with those fixtures it is impossible to have zero tolerance...
Zero tolerance is a term used to set the limits for behavior which applies to sexual harassment or discrimination, not manufacturing...
Your screen name is bodyperson, do you do body work??? Can you install a quarter panel or fender dead nuts every time??? Can you do it once right to the nominal spec??? Do you even have the ability to measure the panels that you install accurately or even at all??? Do you have a dedicated fixture/gauge to measure every panel that you install???
The answer to all of those questions is NO... Every process has a tolerance, some can be held tighter than others... Nobody can build to a tolerance of +/- 0.000