Another batch of Bronze clay, into the kiln. Before and After. A few of the pieces had copper inlay, but otherwise it was all bronze.
It was interesting that the color changed depending on where the pieces were placed in the charcoal to be fired. The pieces with more purple/blue/green were in the first layer of activated charcoal. The pieces that are more yellow/gold were in the top layer of the charcoal. I don’t understand what causes one color or the other, but the golden color was consistent with the top layer, so it might have been exposed to a higher temperature.
I tried applying Butcher’s wax to one of the long “stone” pieces, to see what it would do. The color became a little muted and the piece kept picking up fuzz from my towel because the surface of the bead was rough.
I decided to brass brush the beads and go from there. But where had I put my brush? In looking in my usual spot, I couldn’t find it, but I pulled out a steel brush that I had never used. Worth a try. But then I HAD to find my brass brush to see if there was any difference in how the bronze looked depending on which brush was used. I located the brass brush, and here are the comparisons:
The steel brush was used on the pieces on the left, while the brass brush was used on the pieces on the right. I liked both of the finishes and was glad to see that there was a difference. I soldered posts on the square pieces at the bottom of the group and then used the buffer to get a brighter finish. I then used the Baldwin’s patina and I am really happy with how they turned out. ( The fluorescent light in my kitchen doesn’t give the photo quality I like, but it was night time and I had just finished the earrings below.)
…if things are ever going to dry out up here!
It’s starting to really get to everyone in the Northeast. But, it is certainly good weather for staying at work in the studio. I’ve been working on silver PMC pieces for a jury session at the Center for Maine Craft in Augusta next Tuesday. No studio photos lately, since I’m not trying anything new with copper or bronze clay this week, and I am about to fire the kiln load of PMC pieces. Here are 3 images from Islesford kids that I came across while looking for a photo to put on the blog:
A miniature construction site. (Work was finished for the day.) Whitaker Chaplin,age 5, was the job forman:
Sofie Dowling’s Haiku about horses, age 6:
A painting of the earth by Adele Palmer, age 5:
The copper beads (bottom) have oxidized quite a bit. The bronze beads on left have oxidized slightly more than the bronze beads on right. I applied Renaissance Wax to one side of the necklace, but it did not slow down the oxidation at all in this case. I don’t mind the look of oxidation on these beads. They also polished easily with a Sunshine™ cloth.
In selling jewelry with high polished copper clay components, I would let the customer know that the copper will oxidize more quickly than the silver or bronze. If they want to restore the bright copper finish, I would suggest using a polishing cloth, or include one with the sale of the piece.
After the disappointment of the Baldwin’s patina for these mixed bronze/copper clay rock beads, I used the buffer and fabulustre to bring them back to a neutral colored shine. (I do like the way these look, especially if I am planning to combine them with beach rocks and silver rock beads.)
Next I put the polished beads into a pan with activated charcoal, and put on the lid. Set kiln at full ramp to 800ºF, no hold. Took pan out of kiln at 400º and cooled to 100º before taking the beads out. They looked like this:
I photographed the beads above under a milk jug to diffuse some of the shine in the photo. The colors look sharper here than they do in actual light where the reflective surface minimizes the color. I decided to try more heat with a little more time to see if I could produce deeper, more contrasting colors. The beads went back into the charcoal, full ramp to 900º, hold for 20 minutes, then cool. This is not really what I am looking for. Colors are more muted, and once again less obvious in broad daylight than they are in the photo.
…from a great Maine site. I follow Kristen’s “Maine Maven” blog daily. I was surprised to find myself featured there on Tuesday! Here’s the site:
There is also a direct link in the column of favorite links on the right.
…to say she had 27 Lady Slippers in her yard. The most ever. Yay for wild orchids in Maine!
McGuinness boys: Bill takes some shots while Finn hangs out inside.
Some of these pieces are all bronze and some all copper. But a few were made of a “marbled” copper bronze blend. I love the colors just after firing. Holly, you were right. More color seems to show up after the charcoal has been used for several firings.
I don’t mind a matte finish for earring parts, but I want the beads I wear against my skin to feel smooth. I put this load in the tumbler with steel shot to see what would happen to the surface and the color. Result: More shine, less color.
The “rock” beads looked like actual rocks, right out of the kiln. After being tumbled for 15 minutes, they looked like rocks with jaundice. (Not quite the look I was hoping for!)
To test how much of the color on these beads was from the marbled effect of the mixed clays, I used the buffing wheel and Fabuluster compound to achieve a high polish on the bronze beads. Then I used Baldwin’s Patina to see how much of the copper would oxidize.
I’m not satisfied with how they came out. The last test on these beads will be to polish off the patina and bury them in the hot activated charcoal the next time I fire my kiln. Maybe I can recreate some of the color that came out of the kiln originally, while maintaining the smoother surface. I tried to do this with a torch, but the results were unremarkable.
I finally got some Baldwin’s Patina to try on my pieces of mixed bronze and copper clay. I learned about it from Hadar’s blog, and was happy to see that Rio Grande carried it. It makes quite a difference. The copper turns to a rich color that contrasts better with the bronze. I wish it did not color the bronze at all, but it does, slightly.
The piece on the left has been oxidized with Baldwin’s Patina.
To try another patina, I took the untreated piece on the right and suspended it in a sealable container over a shallow layer of ammonia with a little vinegar added. I then sprinkled the piece with salt. I left it covered for about 6 hours. Love the color! There seemed to be no difference in how it colored the bronze or copper. I will definitely try this again, in a more controlled way. (I wonder if there could be any kind of “resist” used to control where the blue color goes.) I also applied Renaissance Wax to this to see if it affected the color. It didn’t seem to change it much. Below is the piece, with the Renaissance Wax applied.
Next, I took another piece and tried a mixture of oatmeal, cranberry, and chocolate, and applied heat for about 10 minutes.
“Mama said there’d be days like this…”
It was just one of those frustrating days in the studio. Several of the pieces of copper clay I was finishing (sanding), before firing, broke when I was almost done…. AFTER I’d put the time into sanding down the inlayed copper or brass clay. It may have been a “dumb day” but I learned something from it. I am rolling the copper and bronze clay too thin. This happens the most with pieces I want to inlay.
After all the time spent with silver PMC+, I have learned to make pieces fairly thin to cut down on the cost of material. I’ve gotten pretty good at making beads that are 2 cards thick, still having enough thickness to prefinish the piece, with those spongy 3M sanding pads, before firing. This ends up being too thin, for me, with copper or bronze clay.
I’ve rolled out copper and bronze clay to 4 cards thick, then stamped or pressed stuff into it to make a depression for clay inlay. The depression ends up being only about 2 cards thick. It does not take the stress of my handling it, before it is fired. The pieces keep breaking before I get to fire them. This happens more with flat pieces than hollow forms.
After breakage, I fire the pieces anyway, so they can used as test pieces. I have so much to learn about this base metal clay!