You “fellow machinists” might know a bit more about this. I had some shrinkage trouble with some blanks from a manfuacturer a while back, now I’m wondering if they were too thick to start with resulting in the blanks being cut too thin even with standard measurements. Some blank manufacturers make their blanks thicker for machining anyway, so I’m wondering if these blanks are doomed to shrink to begin with?
Blanks don't shrink. Heads shrink. You got shitty blanks.
PU blanks are poured into a mold. The mold needs enough material to compress and pack the cell walls tight. IF the blank manufacture is holding back his materials to increase yield you will result in a blank with a weakened cell wall therefore the cell will collapse or shrink as we see it.
I have seen perfectly shaped blanks shrink before my eyes. Scary to the pocket book! The beginning of the end for a Blank Producer.