A shared cost if you gain added benefits would be a reasonable compromise. Since this is a tool-safe error anyway, it really is a reasonable consideration to tweak the mold along with whatever other changes may be beneficial. My opinion, the vendor should have confirmed and should fix the part. In the end, none of us will end up in court having to defend the right way to interpret ASME Y14.5 or ASME Y14.41. If this is a one off and you really don't expect future business with this supplier, you can push it harder, again, through the purchasing department. If you value this supplier, you have purchasing strike a deal and chalk it up to experience. In the end, I find that these kind of arguments fall under the heading of 'partnership agreements'. Not knowing the design intent, it is difficult to know what the 'right' way to define this really is. Variation of that angled face will vary significantly if the radius tolerance is even 20% of 0.5mm. In design, this is very poor control of the angled surface if its position on the diameter is indeed a design element where the overall OD is not as significant. The vendor is right in that rounds are typically calculated later and are not a critical element. In this case, I too would have put a clarifying view on the drawing or a reference dimension of the smaller diameter. The part was made using an assumption that was not factual or supported by the submitted drawing.ДЄll 'proper' interpretations are already covered.

Asme y14.5 dimension not to scale