Monday, April 1, 2013

Painting Practice Pieces

I made a quick practice piece to check my firing schedules and the paints:

For some reason (other than being an SCA herald?) I like to use an Ancient Crown for my practice pieces. I mixed a small batch of Reusche 1059 tracing black, and a matting color of about 50/50 Reusche 1220 A gray green and 1110 bistre brown #7. I did the matte, waited, very roughly traced the ancient crown, waited. I removed the matte from about 2/3 of the crown and did a thin highlight around the entire border. Fired it, applied the silver stain, tried a new blender, and fired. This shot shows some of the matting coming off:

 I'm using Reusche 1384 silver stain, Yellow #3. I had a previously mixed batch. I took a small bit, diluted with lavendar oil, and diluted it too much. Then I kept putzing about with it, and it was too dry when I went to hit it with the blender. Eh, I thought, it's a test piece. Fired it again:

 I am not unhappy with it. The matting is too light, the lines irregular and poorly traced (but it was a test piece), and the silver stain uneven. The only actual problem I've noticed is metalling where my silver stain is thicker. It happened once before, as well:


I checked my firing schedule (I'm using schedules from Williams & Byrne), and I noticed that my current schedule only goes to 1040°. Metallizing, as I understand it, normally happens when you fire too hot. RP 1384/Silver Stain, Yellow #3 has a listed firing range of 1050-1080. I'm going to do two more tests this week, firing to 1020° (20° below my current schedule) and 1060° (20° above) to see what the effects are. Viewed directly on the stain is pretty, this may be something I end up having to live with, because I can't image 30 degrees below the listed range is going to make it better, and going higher should make it worse if this is actually metallizing.

(Update, 4/17/13)

I ended up with interesting results. The test piece fired to 1060°, just inside of the manufacturer's listed range, turned out horrifically bad. I went ahead and fired it on a chip with a blue enamel I have plans for, and this was my result:

Horrible metalizing, "yellow mother-of-pearl" as I expected from Williams & Byrne's books, their description of overfired silver stain. It looks horrible in both reflected and transmitted light.

The chip fired to 1020° was relatively the same as 1040°:

Looking straight through it, its functional, but there are some off spots and in reflected light you can see its still not right. Thirty degrees beneath the listed range, and it's still not right? I started to suspect I was firing for too long, then, because surely it couldn't be too hot...

Checked Elskus, seeing what he had to say on the matter. Silver stain, according to him, has a functional range of 950° to 1050°! I'm still on the high end, according to him. Ok, one more chip, at 1000° then.

This picture doesn't do it justice. Beautiful and quite even. I stared at the chip for several minutes, held it up to various lights, placed it on my lightbox. I put it by my computer and picked it up ever few minutes for an hour, staring. 1000° it is, then, and that temperature has been working great for me. As the masters wrote and write, experiment and experiment some more...

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