For me, it is duifficult to tell where the crack is from the photo.
Can you tell us the material? I am assuming it is something that does not take well to fast cooling cycles that cause built in stress. Of course it could be a tool design problem where there is insufficient clearance to remove a brittle part, which is why the warmer tool doesn't cause a crack.
Did the part ever run well?
It is hardly too strong to say that the Constitution was made to guard the people against the dangers of good intentions. There are men in all ages who mean to govern well, but they mean to govern. They promise to be good masters, but they mean to be masters.”
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