On Wed, 20 Aug 2008 11:54:46 -0500, dpb wrote:

RLM wrote:
...
Cut it with a box (utility) knife, broke off clean and sanded the edge.

This board is 45mm x 90mm before cutting. I cut it in half and the holes
align with the mounting holes inside the box.
...

I can't imagine why the OP thinks he needs such a tolerance anyway (even
if is a typo and meant 0.5 instead of 0.05 mm)...

Perhaps he will share what it is that he is building. My curiosity is up.