"Target arc height" is a relatively-new concept and is now embodied in SAE J443. Verification is to be carried out to confirm an arc height predicted by the saturation curve - rather than one of the measured points. For your data the target height at four passes would be 4.9, with SAE J443 specifying that a single-strip verification test must give a deflection within +/- 0.0015". Your customer has reduced this to +/- 0.001" to give a range of 3.9-5.9 for your example and added a further restriction that the minimum value should exceed the drawing minimum specification of 4. That leaves you with having a range of 4> to 5.9. Personally I believe that the allowed range should be reduced considerably but meanwhile we 'play by the rules' even though, as you correctly point out, the true intensity at verification would probably be below the drawing requirements. "Target arc heights" are very useful for multiple strip locations.
TSP articles (Fall 2015 and Summer 2016) cover this topic in detail.
Last edited by Socrates; 03/11/17 12:48 PM.
