Simulated Copper Finishes for Exterior Wood

Here's a handful of ideas for putting a copper look on a wood post. September 5, 2010

My customer requested a wooden (or other material) sign post to be painted to simulate metal copper (finish). I would like to spray a material on the post, but am unfamiliar with requirements to do this. Would automotive finish or a baked-on finish work? Iím not sure this is even possible, but if anyone should have a suggestions as to how to do this (and have the finish last), it would be greatly appreciated.

Forum Responses
(Finishing Forum)
From contributor O:
I imagine you will get painting suggestions, however the easiest way to get copper that comes to mind is to lay down a couple of coats of gold size and then apply copper leaf. Most any hobby or craft shop will have imitation gold leafing supplies and something in the way of a copper leaf. They will also have a metallic wax and metal product called "Rub and Buff" which comes in copper also and might do. Although exterior use of that wax product is an unknown to me.

From contributor S:
What kind of copper look is he looking for - penny bright, antiqued, patinated green? Rustoleum makes a copper hammercoat finish for heavy machinery in a rattle can. It's a fairly good faux copper, it works just fine on wood and you do not have to let it hammercoat. Just spray it with lighter coats than a full wet coat and it won't hammer react. They also make a verdegris green that misted over the copper here and there is fairly convincing as well as a couple of different bronzes that do a nice antique misted on. I'm pretty sure it is rated for exterior but you'd have to verify that if the sign is for outdoors.

From contributor D:
I just used a product called Plate All and is made by mixing ground metal powder, resin, and catalyst. You then spray it on your piece. I have more of this product left with copper one of the metals I have.

From contributor C:
Why not find a metal worker with a brake and have him wrap and solder the post? Why copy when you can use the real thing?

From contributor W:
We do copper finishes on various substrates from scratch. To obtain the actual luminescence of copper is very difficult however Luminore does make a product which is 95% copper powder mixed with a hard epoxy and buffed out. Itís expensive and requires some expertise. Other options: Mica powder in copper hues mixed with high gloss clears gives a good result however requires good skills with the gun and generally should be antiqued with oil based artists paints made into a glaze to trick the eye.

Real copper powder requires a special formula by the manufacturer so as not to fade in direct sunlight and is available but I have found that the mica powder is much more forgiving. Such copper powder is mixed with solvent based urethane or waterborne urethane and lightly sprayed from spray bottle with antiquing solution to impart an actual verdi gris. Leafing is very good but the durability comes into question. The item must be leafed many times and coated with gloss solvent based clear.