Facebook, you either love it or hate it or, like me, you ignore the rubbish, ignore the all controlling info grabbing works in the background and simply use it to communicate with long lost friends, get to know new ones and learn new things.
Once in a while an unassuming gem comes floating by in the newsfeed, like a post from Roberto Brazzi who showed some wonderful Raku pieces fired in a Hotpot "Raku-Ando".
A what? Exactly my thoughts! It appeared to be a microwave kiln for ceramics, cutely called Hotpot Raku-Ando.
I've been interested in ceramics for as long as I remember and having an option to make some in a microwave... now that got my juices flowing! I ordered the Hotpot from Roberto all the way in Sardegna (Italy), bought a dedicated microwave oven and Raku clay. I made a few pendants and 2 small pinchpots ready to be fired. They dried for well over a week.
It was FREEZING that morning but needs must, so hot coffee at hand, gloves on and out we went (Roberto advised doing the first firings outside due to the smell.... that was sound advice. It stank!) Althought you can apparently fire from bisque to a glazed piece of ceramic in 10 minutes in the microwave, you still need to sit through the bisque phase first - roughly an hour.
After carefully checking that the kiln had reached the required temperature or at least the right colour and glow, and after letting everything cool down completely it was kiln opening time. All the pieces came out intact and sounding right :) On to the next phase: Glazing. Obviously, toooooo keen to get a result and not knowing much about glazes at all, I applied the glazes as per instructions. They were low fire glazes recommended for this clay so I had at least that bit right. Or so I thought...
Looking dull and uninteresting and really exciting how these were going to come out of the kiln!
10 minutes in the Hotpot and I would know :)
NOT what I was expecting. 1 pendant exploded, the other 2 had an ugly colour.
- there is oxidation and reduction firing - I got the wrong glazes for this type of mini kiln
- the pieces probably contained some moisture after being glazed and 10 minutes in the microwave was heating up the pieces too fast without giving them the time to evaporate any moisture properly.. resulting in BANG! - above all, i learned, in ceramics, never get too attached to your piece... Things happen!
With all this in mind, I washed the glaze off the 2 other pots and applied a different type of low fire glaze to the little pouring pot.
After letting it dry for over a week, I dared to put it in the hotpot. I did not have to wait 10 minutes. Closed the door of the microwave, turned it on.. and BANG it went within seconds. Obviously something was terribly wrong. I opened the hotpot and found a thousand pieces of what had been that little pot. Again not really sure what caused the issue. I was too disgruntled to take a picture of that!
Roberto followed my experiments from nearly 2000 miles away and he assumed that maybe the clay had not thoroughly fired to bisque temperature. Hard to tell in a microwave environment. He suggested to run the last remaining pot through the bisque cycle again followed immediately by the glazing cycle. This was before: Purple glaze on the textured bottom of the pot - Sunburst yellow on the inside with orange on the rim and a few randomly places drops of the same.
This was after:
Not a success but also not a complete failure. The little dish was in one piece. Quite happy with that.
The outer glaze did not adhere well to the bottom and completely obliterated some of the texture, which may have been caused by getting interrupted while glazing and losing track of the amount of layers I had put on (you need 3 for good coverage and as you can see from the before pictures... hard to tell!) The sunburst glaze on the inside blistered, big time.., so probably I overdid it a bit with the firing this time. The orange glaze on the rim, and what were supposed to be decorative drips of the same glaze on the inside, were all blister free. So 1 thing right at least! I scraped some of the blisters off (carefully and with goggles on!) and painted the inside with a couple of layers of acrylic paint so I can use it without ripping the skin of my fingers. I also added some acrylic paint on the rim to mimic the purple, rubbing it back off to give it a worn look.
I'll keep my wee crater pot, the first pot on my ceramic journey :) It's not perfect but will be a good record of how I started. Onto the next experiment!