Some say using a thin sheet of 0.2mm aluminium on top of the board - an entry board, can help. I get a piece of wet and dry sand paper and go over the board before i start the plating process.
Trev
----- Original message -----
> I'm looking for a method to deburr my ground vias to smooth the drill hole for
> copper plating. I do RF prototypes and the PCB has a lot of ground vias. In the
> past, I used 2 pass drill to drill the hole, the 2nd pass, one 1 mill smaller
> but it doesn't seem to help much. I can increase the diameter of the via hole up
> to 50 mils.
>
> Thanks
> Lanny
>
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