How can one speedup the oxidation process of copper which gives it's patina?

Answer 1

Put it in an oven, or thermal chamber, and heat it up to 150 - 200 F for a couple of days. That'll oxidize it pretty quick.

If "it" is too big for an oven, try covering it with heavy clear plastic and setting it in the warm sun (i.e. make a crude oven outside).

Answer 2

A solution of salt and vinegar. Brush, dip or spay on clean copper. Clean with soap and water when color is achieved. May need to clean with salt dippred in lemon. Don't touch with your bare skin becasue the oils from your hands will make the patina not stick. By the next day there should be a good patina on your surface.
Yould also try this product: http://www.modernoptions.com/

Answer 3

tlbs is right, and another way to increase the rate of reaction is to increase the concentration of oxygen. Running pure O2 would help, or if you can't do that then set up some sort of fan to constantly replenish your air. Be careful using pure oxygen in a furnace environment though, if you have exposed leads your O2 can ignite.

Answer 4

Spray it with bleach or put it in a very hummed location. Bleach will make it tarnish over night. The copper needs to be oil and wax free.

Answer 5

I'm not sure what its called, but there is solution you can buy that does this. Check at places that have supplies for foundry work. This is a common practice for people that are casting bronze scupltures.