Sounds simple, right? Not always the case, as I was reminded several times recently. The task was supposed to be simple: Coasters – 4 inches square. However, with this mold I have only tried a single sheet of iridescent glass and then another sheet of a color usually cutting them both the same size, and placing them on the mold with the iridescent side facing the mold. Someone challenged me by asking for coasters made using this mold, but with yellow and grey similar to a plate they had bought in my Etsy store.
I was a bit leery, and should have thought about it more, but laid the pieces up exactly as I had with a single sheet of color. I put an iridescent clear glass face down on the mold and then added the yellow and grey colors. I was sorely disappointed when I opened the kiln after firing as instead of nice straight lines as I had with the plate, the lines were wavy. Artistic, perhaps, but not what I wanted. Sorry for the bad picture below, but I didn’t think ahead and take a better one.
To solve the problem, I made the coasters without the mold, laying the colors on the kiln shelf and then adding the clear iridescent to the top. After the initial fire and maintaining the straight lines of the glass pieces, I turned it over and laid the iridescent side of the fused piece on the mold and refired.
My next coaster was just 5 stripes with a swizzle of dichroic glass on top. I knew I should have laid the stripes down first on the kiln shelf with the clear on top, but since the center piece of glass had an iridescent coating, I wanted it on top and so instead, I went against the whispers in my head and put the clear glass down first on the shelf with the stripes on top and then added the dichroic swizzle. Not only were my lines not quite straight especially at the edges, but where the dichroic glass melted into the colors, the extra glass actually caused the line to bulge disrupting my straight line. I should have listened to my whispers. If the clear glass had been on the top, the swizzle made of a dichroic layer on clear glass, would have melted into the clear glass on top but the stripes below would have been unaffected.
Why am I sharing this? If you really want to keep your lines straight, the stripes need to be against the kiln shelf as that first sheet of glass is less fluid and can therefore better maintain the lines you had purposefully created. If you really wanted that layer to be the top of your plate, you can always flip the plate after that initial fire and fire polish it.