>> Jeff Heiss wrote:
>>
>> The top of the board is etched first. There
>> are four alignment crosses on the top and
>> holes are drilled through the center of the
>> cross. The bottom is aligned to the holes.
>> I have not done the BGA vias yet since the
>> drill bits are breaking but I will try to
>> solder wires thought the board to connect
>> the top and bottom. Then will I snip the
>> wires flush between the BGA ball pads and
>> solder the BGA.
Bottom holes dont have to clear pads/balls so
can be a lot bigger.
Use a high temp solder on the vias and 60/40
on the balls.
Use a solder mask of some kind.
Get used to frustration.
Possibly just make a CNC drill and some
through hole plating tanks. It might be
quicker in the end.