What exactly do you mean by cratering? 6012/a600 does not use that exact term, it uses cracks, plating separations and lifted lands. Thats why i ask. Also any acceptance criteria in 6012/a600 for pth's and annular rings after thermal stress are after 1x thermal stress, not 6x.

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> On May 1, 2017, at 3:58 PM, "[log in to unmask]" <[log in to unmask]> wrote:
> 
> Fellow TechNetters;
> 
>   Is PTH annular ring pad cratering permitted after Thermal Stress, 6x?   What is the allowance?  I don't have a copy of IPC-A-600 Rev F before me.
> 
> Victor,