Archive for September 24th, 2008

I did a really stupid thing last week. I was cutting a 12″ disc using my new second-hand-from-eBay Silberschnitt circle cutter when a slight crack appeared running in from one edge. At the time I was pretty pleased with myself for getting the disc out neatly without it breaking across at the crack. I thought it would close up again in the kiln. Silly me. Probably that would have been the case if, a) I had been using two layers of 3mm glass rather than one, or b) I had thought to place part of the design over the crack, thus effectively providing the necessary double layer at that point.* As it was, with a firing to 1345° for 20 mintes, the crack opened up a couple of millimiters over a length of about two inches. Useless. And – by my standards – an outrageous waste of a square foot of glass. Not to mention that some of that glass was the ludicrously expensive sunset coral.

I have spent much of the last week mitigating this error. Otherwise known as throwing good time after bad.

First I thought about the possibilities of a) and b) above and decided to place another “leaf” over the troublespot where the crack had opened up. So the next night I did that. It didn’t work. The design could take the extra element, but the crack was still there, albeit smaller. A couple of days later I visited my friend and begged some coarse clear frit for repairs. According to Bullseye’s catalog, the coarser the grade of frit, the clearer it will come out of the kiln (I think they are talking about casting), so I figured I should give myself al the help I could get at this point, and the poor disc was already looking a bit sorry for itself and was risking devitrification with every additional journey into the heart of hotness…

Well, that sort of worked. At least there was no hole in it any more and there was some chance of turning it into a passable dish. Last night it went back in, in one of the new molds (the one they call the “round slumper”, which baffled me until I got the exact dimensions and then decided seems to mean “flattish dish”, but maybe they think that might look silly in a catalog).

OK. Not great. But OK. The mold is good, anyway. The dish is in the cellar, already.

*Put succinctly for the uninitiated, glass likes to be around 6mm thick. If you layer it thicker than that, it will tend to flow outwards at heat, if you use less thickness – i.e one layer of standard fusing glass – it will tend to contract as it tries to puddle into a 6mm-thick mass. Both these problems are minimized, if not eradicated, by a conservative firing schedule.


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New molds!

I finally went mad and bought some molds. Proper glass molds, from Bullseye, rather than the unglazed bisque from the ceramic cafe supplier I usually get.

I have mixed success with the bisque: firstly holes have to be drilled into it and I’m ashamed to admit I’m so pathetically terrified of the drill that I make my poor husband do it for me. Then it can be his fault when the mold breaks. Which happened the other day. To the expensive, interesting chip-and-dip mold I’d been most looking forward to using. Ah, well, never mind. I might be able to patch it up with plaster.

small round dish, small square slumper and two tiny unglazed bisque dip saucers from the ceramic cafe supplier

Kelvin loaded with new molds: small round dish, small square slumper and two tiny unglazed bisque dip saucers from the ceramic cafe supplier

I did actually have one Bullseye mold already, and it was an expensive one too, but I think I made a mistake with it. I wanted a large bowl, but I got one that turned out not to have a flat base (I think they call it a “ball curve”) which is OK, but somehow less useful to most people than the regular kind. I think it may be disconcerting to see it wobble when you already know it’s fragile. Possibly it needs a stand of some kind…?

So, anyway, I have a friend who just bought a kiln, and she has – unwittingly – been pushing me into spending habits. I think I had been too stupidly parsimonious, so I have prtty much no glass and no molds for a year and was pretty frustrated. She came along, with a bit of a budget, and immediately got herself kitted out properly, putting me to shame and making me realize that I was never going to get anywhere without a bit of investment. I bought enough nice glass so I can do more than mess about with float and the odd bits of float-compatible stuff I got with Kelvin (his trousseau? his layette?) which is mostly what I did.

Joy. Revelation. Renaissance.

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