Rounding the corners of dice - how would you do this?

[taxque]

The edges of these dice were actually cut using a pantogragh overheard router and a 45 degree chamfer bit. The indexing pin was moved in a circular pattern and the dice were rotated on each face as the edges were shaped.

It seems that I should be able to mount the dice on a sled/carrier board and use a chamfer bit to move about the top edge and accomplish the same task. I would have to rotate the dice so that all 6 faces are machined but it seems like in should be doable. The key is to figure out what diameter of circle is needed to face the edge and what the cutting depth should be for a 4.5" cube.

Any one ever done anything like this or have any suggestions on how to do so?

Greg