Dave Mucha wrote:
>>>This is not for the faint of heart nor a simple one shot project.
>>
>>This is very true. The electroplating, and application of your own
>>photoresists is the other major parts of the PTH process.
>>
>>In addition to etching, and photo imaging, you must;
>>
>>1) cleaning PCB surface to prepare for electroplating.
>>2) ability to apply your own dry film photoresist
>>3) give holes the ability to plate.
>>4) setup acid copper electroplating tank with proprietary additives.
>>
>>There are several methods of doing (3), such as with carbon
>
> dispersion,
>
>> electroless copper solutions, or with palladium colloid
>
> solutions. I
>
>>believe Markus's setup is using the palladium colloid solutions.
>
> All
>
>>three processes have their problems, and I would say the most
>
> critical
>
>>step in the process.
>>
>>Let me know if you have any questions.
>>
>>Adam
>
>
> I think we have all been looking for a simple way to plate thru-holes.
>
> I know that when I run into this problem, I try to use a resistor or
> some other thru hole part as the connection and then solder both
> sides.
>
> Since most of use use boards that are less than about 6" x 6" the
> size of a tank should not be terribly large.
>
> Any ideas on a a simple way to do plating
>
> Dave
If you want to start copper plating then I suggested go to your local
electroplating supplier and ask for the chemicals to do it.
There are three parts to the soltuion.
∗ Sulfuric acid
∗ copper sulfate
∗ proprietry organic additives.
The additives must be bought from the company. they might give you a
free sample if they are in a nice mood. You can plate copper with just
copper sulfate from the garden store and some sulfuric acid from old car
batteries, but the plating results will be poor. The additives give
uniform and smooth deposits. Any old electroplating book will have
infomation on acid sulfate copper electroplating.
For starters, a "conventional" bath could be made from 150g/L
CuS04.5H20, and 50g/L H2SO4 without organic additives.
Electroplating is only one stage of the PTH process.
Adam