When to Apply Patina?

 Is patina able to be applied days later or does it need to be applied immediately?

The best method is to clean the solder with non-metallic mild abrasives. If the bare solder is left for a while, the solder needs to be cleaned again, as oxidisation begins immediately. Any oxidisation inhibits the patina reaction and provides an uneven finish.

Once the solder has been cleaned with non-metallic scrubbing, wash in cold water, dry at once, and immediately apply the patina.

Can you leave the solder silver with polish/wax until you decide which color and go back later? 

It may be possible, but it is not a complete protection against oxidisation. It will, of course, reduce the amount of oxidisation and make the clean up a little easier. But, any polish needs to be thoroughly cleaned off and the solder scrubbed clean, washed, and dried before applying patina. So it may be most simple to cover the soldered panel with plastic cling film (Saran wrap?), or in a sealed plastic bag until it is time to clean the solder and patina.

In both cases the important elements are to

• clean back to bare solder,

• clean with water,

• dry immediately and

• apply the patina acid right away.