Copper Flower Question - Residue from Annealing

[Dustin Quade]

Last year for christmas i made my girlfriend a copper rose and she loved it. In fact she loved it so much that she wants a new type of copper flower every year for christmas. So yea here i am this year making a copper tulip. My issue / question is this. Last year when making the copper rose i ran into a problem. I was told that when working copper you need to anneal it when its time to bend it all into shape otherwise it will be too difficult and wont work properly. I was told that to do this you heat the copper in the forge and then quench into water. But when i did it the copper became completely covered in a black finish which i had to very very carefully sand off without bending up the copper because it hardens back up as you bend it. I want to try to avoid that this year so does anyone had a way of annealing the copper that wont leave this residue? Quench in oil? Air cool? Use a toaster oven or regular oven? Any tips or tricks would be greatly appreciated.

Thanks,

[ThomasPowers]

It's called pickling to remove firescale and Sparex #2 in an old crock pot never to be used for food again will do it nicely.

(you can buy the active ingredient cheaper from a pool supplies company IIRC)

[Kozzy]

In a pinch, you can use a warm vinegar and salt pickle--1 teaspon salt to a cup of vinegar.  Hate the smell, personally--a LOT.

There are also recipes for citric acid pickle online which use standard grocery store "fruit fresh".  According to what I read, they tend to need a hotter temp to work well which increases the safety issue a bit.  I haven't used citric acid for anything but stainless pickling and that was cold with commercial solutions.

Thomas Powers has a pretty good idea if you intend to do more roses.  Crock pots are cheap (and the small ones are often incredibly cheap at Christmas as desperation gifts) and the Sparex #2 seems to be excellent stuff.  It'd likely be worth going this route for anything more than a one-off rush.

Be sure and read up on baking soda neutralization also.  You can probably get away with a simple thorough rinse for a one-off but neutralization is the right way to go (and cheap).

[SLAG]

There is another way to approach this problem, with a solution.

People who do copper enameling, coat areas of copper that are not covered with enameling solution with a product that prevents the coated copper from oxidizing  during heating  in the kiln.

The solution prevents oxidizing of the coated copper. After firing in the kiln, the resist coating flakes off leaving bare copper.This treatment prevents black copper oxide from forming, in the first place, so there is no longer a need to sand it off.

Try telephoning ceramic supply stores for the product. Or search the net.

SLAG.

[Dustin Quade]

Thanks for all the replies guys. I will try to invest in the croc pot and sparex next year but i dont have time to get it all in this year. I think i will try a pot with vinnegar and salt. Im used to the smell because thats how i used to etch my blades before i got my hands on some ferric chloride. I will be sure to let everyone know how it goes.