Letter 2662

Heat coloring Copper

- I have tried all forms of heat ( oxy/acetylene, electric oven and home stove top gas) to produce the effect seen on this butterfly refrigerator ornament, but cannot duplicate the vivid colors. Since I have 2 of these I assume it can be duplicated. Is another ingredient ( oil?) added or is it a matter of a consistent temperature? Mel Owen - Texas - I think chemicals were required to achieve this. I've said it a lot on this site, but borrow or buy a copy of "The Coloring, Bronzing and Patination of Metals". Ted Mooney, P.E.  finishing.com Brick, NJ . The coloring produced on the butterfly can be done with heat. You don't have to slather your work in harmful chemicals to get some great coloring. You have to experiment like never before and work with the heat from any torch and "paint" the copper with the flame. You can try working with oils as well. I once was annealing some brass in a kiln and I took it out too soon for annealing but the oil from the factory must have still been on it because it produced some amazing colors and patterns.(The pieces of metal were framed and hung in 'Out of Hand Gallery' in Lunenburgh, Nova Scotia!) Grease may be easier to work with than oil. You have to play a lot with the torch because it is easy to heat the metal too much and the colour will go to a yucky brown. Also try working with folding the piece and annealing it. When you open the work you get some interesting colour patterns due to the amount of oxygen that gets to the metal in the folds. The trick is to play! Have fun and ALWAYS WEAR PROPER SAFETY GEAR! PROTECT YOURSELF AND YOUR ENVIRONMENT!!! M.Jardine The Copper Meadow - farmington, nova Scotia, Canada

I HAVE NO PROBLEM GETTING THE COPPER TO CHANGE TO ALMOST ANY COLOR. This is the copper after heating it.

My problem is losing all the blue,red, and purple colors, When I apply any product to keep the copper from tarnishing. The other photo is after the product is applied.

I have applied a large variety of products and none have worked to my satisfaction. I will be very pleased for any advice you can offer.

SONNY GRAHAM
- OZONA, FLORIDA, USA

Yes, I have the same situation as Sonny. I have tried spraying the heat-colored copper with clear Krylon or lacquer, but it seems to oxidize beneath the surface of the clear sealer (about 6 months later). How can I preserve the heat-produced colors without having oxidation? I also often have a roughened, sanded surface, so I'm not sure if wax would be an option.

John Waters
- Phoenix, Arizona, USA

I unfortunately don't have good news for you, Sonny or John. Some portion of the nice coloration is from diffraction patterns rather than pigmenting -- like the rainbow sheen of a drop of oil on water. The oil isn't really rainbow tinted, it's the way the very thin layer prisms the light. As soon as you put any clear coat of any type on your piece, it's like trying to lay a sheet of glass over that oil rainbow to preserve it. The colors that are "really there" will be retained, but the diffraction colors will disappear.

Ted Mooney, P.E. 
finishing.com
Brick, NJ

Try using OIL-based polyurethane instead of lacquer. Or another oil-based product.
The problem with water based products and many of the lacquers which are acidic is their reach with the copper creating another patina, not necessarily he one you want.
I have not tried this with colors like yours, but I've used it on both bare brushed copper and sulfurated potash patina copper ( mostly dark colors) and it preserves most of the color.

I have a copper dining set I made about 7 years ago and it's still pretty much same color (that picture is when it's about 4 years old).

I just experimented with several brands and price does not seem to make a difference. Cheapest worked same. Polyurethane also has the advantage of being flexible, unlike lacquer, which will have hairline cracks after a while for temperature expansion and shrinking of the copper and will lose it's protection.

I've tested it by bending a coated piece back and forth and them leaving it in salt water for a month with no visible tarnish while the lacquer piece turned black.

Alik Perakh
- San Diego, CA

I am a hobbyist working on a table top project looking for a way to treat copper. I am looking for a dark rainbow swirl effect and nobody has been able to help. I also would like to know what to use to seal it after this affect is achieved.

Jeri Bond
hobbyist - Syracuse, New York, USA

Please tell me where I can find help. I want to heat 110 copper sheet .032 gauge .. I want to bring out areas of orange, yellow, red, etc. What common tool can I use and how hot should it be? Is there a website, article or book that you can suggest? THANKS BUNCHES

Dottie Cesario
hobbyist - Tampa, FL, USA

I've managed to produce a wide range of hues on copper with an ordinary propane torch. The trick seems to be in heating the copper to a high temperature and then using the torch as you would a paint brush. Heat one portion of the piece until color starts to appear and then experiment. A long time under the torch close to the heart of the flame produces pale greens, silver, and gold. A quick stroke with the edge of the flame produces blues. A longer time at the edge of the flame produces reds and pinks.

Joe Nicholas
- Kansas City, MO, USA

I am a hobbyist making copper wind chimes. I am burning the copper chimes with a propane torch to bring out the different colors in the tubing. When I put a finish on the pipe, the colors fade and and some colors, like purple, disappear completely turning to orange. I've used lacquer, Rustoleum products, shellac and a variety of water based (acrylics) clear finishes used for hobbies and purchased at hobby stores all with the same results. Does anyone know of any kind of finish either brush on or spray that will not change the oxidation of the pipe.

Tony Wright
hobbyist - Huntington Beach, CA, United States

We are trying to create a tropical sunset scene in sheet copper and would like to embellish the work primarily in blue and red hues. A metal worker mentioned applying bromide salts to the metal prior to heating with a propane torch. Has anyone had any success with this method? Any other recommendations?

Thank you!

Bob Yeamans
- Columbus, Ohio, USA

I would like to know what process I need to employ in order to discolor either copper or brass. I believe what I want to do is etch the metal, but I don't know what chemicals to use or possibly how to heat it to accomplish this. I'm working on a a logo which will be large and want to use discolored and/or distressed metal. Any help you can offer will be appreciated.

Thanks

Paul

Paul Le Pain
artist - Dunedin, Fl, USA

I have had great success keeping the blues, purples, and reds in my flame treated copper. I worked with my local powder coater and found that a clear finish baked at half the time usually required, does the trick. It allows the powder to melt to a clear glaze and give the copper a depth that spray on treatments don't allow, but by leaving it in half time,the copper doesn't heat up too much to change color.

Emily Lewis
- Burlington, NC, USA

I am interested in what you have discovered re: coloring of copper with varying temperatures. For a different reason, though. My apron front copper sink was damaged, and it had a "Fire and Ice" finish on it that was beautiful. It had to be polished off during the repair, and I would like to replicate all the colors that were represented. (I realize I can't replicate it exactly.) Thanks for any info!

Peggy Thomas
- Amarillo, TX

Hi

I am trying to preserve the color on HEAT patinated copper. I have tried water based Incralac, paste wax, spray lacquer, Krylon 1301 . The best results have been the Krylon. However it still changes the color. Do you think that a solvent based Incralac will work better at preserving the color??? Thanks for you input.

Bruce MacKimmie
- Moss Beach, CA, USA

I would like to know the best way to bring out color in brass using a blow torch. Should I use something in addition to heat. Also, what is the best way to keep the colors? Should I polyurethane it? I want to make art objects with copper and get the beautiful purples and golds from the heat.

Lynn Schmoock
hobbyist - Hillsborough

I have tried many things to ensure that my copper fountains remain nice and shiny waxes and acrylic finishes. But unfortunately of all of them the worst thing I have found is putting a lacquered finish on them. Whether it's the combination of outside elements or the water or both I don't know but it begins to discolour after a couple of months and the finish begins to really look drab.

I am experimenting with a company in the UK that works with clear powder coating, and I am trying to get something that is ok to use outdoors with water over a long period. It might be a while till I get a decent result but if it works I'll post the info later in the year.

Craig Humphreys
- London, UK

I create metal sculpture for patio and poolside with 18 gauge sheet metal. I'd like to add random color (blue and whatever other hue possible) to the sculpture using my oxy-acetylene torch. How is this achieved and what settings do I use on my regulators? Have looked for books on the subject, but can't find any.

Polly Fisk
metal artist - Dallas, Texas, USA

Getting red from copper with a torch. I am new to coppersmithing and have been trying to get the color in my leaves and butterflies when I cut them out with the torch. Does anyone know how to do this? Is it in the regulator settings or what? I have tried everything.

Jeremy Whitmire
coppersmith - Copper Country, MI

How do I use potash to color my copper project? I'd like to find out what the application is and how and what do I mix the potash with?

Ross D Laird
Primal Iron Originals - San Diego, CA

When I do small projects on copper, I usually get a nice fire-scale effect by "painting" the parts I want to color up with flux (flux for hard solder), letting it dry, then turning the piece over and heating it from the back.
I usually heat it pretty hot to get a nice red color, but keep the flame away or it'll burn the flux and turn a funky color. Use the flux lightly...

Jessica Schafer
- Santa Cruz, CA, USA

If you want to turn copper red heat it as hot as you can get it without melting it then dunk or spray it with water. When I make a rose from copper this will make a very bright red rose.

Lyle Wynn
blacksmith - Flowood, MS, USA

I understand the problems of losing colors after heat coloring. I do steel coloring. The best way is to use cold roll steel. After you obtain the effect you want, leave it set over night or longer and let it cool down. Then I use a spray called EnviroTex high gloss. Hold the can at least 18" from the piece working on and spray a light coat. Let this dry and then do the same thing again. Dothis several times but DON'T GET TOO CLOSE. You might lose just a little lighter blues but the deep blues and purples will stay. Also the clear powder coat will work at half the baking time. When the powder starts to glaze over I shut the heat off and pull the piece out of the oven There is a new low heat clear powder coat coming out. Don't have the info on it yet. I get the envirotex spray at Ace harware. It's on the internet also. just type in search engine Envirotex spray.

Mike LeMaster
welding - Delta Co.

I've been working with copper for about 13 years and have gotten some beautiful iridescent-like patinas with "liver of sulphur". It's a benign substance, available in crystal form from any chemical supply house or in liquid form from any garden centre -it's the orange liquid part of Dormant Oil Spray that's used to spray fruit trees in late spring and cheaper than the crystals. Liver of sulphur is the substance that smells like rotten eggs (remember stink bombs?), so take care where you use it.

It should be mixed with water and makes a very light brown to black patina, depending on the ratio of water to liver of sulphur. Less water = darker color. I get the nicest iridescent coloration when I apply with a brush. Experiment with different ratios on scrap until you get an effect you like. The effect is instant and if you don't like it, clean the copper and try again. The patina isn't stable so it has to be lacquered after the desired effect is achieved. Additionally, the water mixture loses viability fairly quickly, so only mix what you'll use in a few minutes -30 minutes, tops.

I hope someone finds this useful.

Cheers!

Kathleen Donaldson
- Kingston, Ontario, Canada

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