Any of you who have been following me for a while might know that I am a contemporary slipware potter… I use coloured slips (liquid clay with added pigment) to decorate my pieces rather than glazes. To date my work has been inspired by the breathtaking turquoise blue that I see each summer on North Uist’s shell beaches. However the sea can be a multitude of colours from blue, to grey, to green and for some time I’ve wanted to expand my colour range to allow for these.
Until now I have been using ready-made slips but I’m finding this both limiting and expensive. To make my own there are two alternatives: to buy manufactured stains, or to blend my own combinations of oxides. One day I hope to do the latter but for the meantime I’m going down the stain route. I’ve been prevaricating about this for ages… Why is it that the things you think are going to be tricky end up being pretty straight forward? Maybe it is as a result of thinking about it for so long that I’d worked out most of what I needed to do in my head before starting.
First I made a series of test tiles out of clay slabs – each one with seven impressed areas to apply the different combinations of colour. Then I made endless pots of slip using measured amounts of dried waste clay, water and stain. These were left to slake overnight and then passed through a fine sieve to ensure a smooth consistency and proper mixing of the pigment. With each colour I did three tests –
Dilute: where incremental amounts of water were added to the slip to thin the colour
Lighten: where additional quantities of white slip were added to fade the original colour
Blend: fading one colour into another to create other colours
126 combinations in all.
There are some results that I really like, and some that need a little finer testing before I achieve what I’m after… but all-in-all not a bad first attempt.
Last week’s bisque firing went well… now I just have to get everything glazed and back into the kiln. I’ll post some images once they’re finished.
It’s been another busy few days trying to get work ready for Potfest in the Pens, and this week I’ve been making large breakfast cups. I’m still getting used to the process of making larger quantities and trying to get some kind of uniformity. I enjoy the repetitive nature of the relatively straight forward elements, like pulling handles (see above). However I’m finding trying to throw twenty cups the same more of a challenge. I don’t want them to be identical as they would no longer be unique, but I do want them to sit well together in groups. This means that they not only have to be the same height and diameter but have the same thickness of lip; height of turned foot; and shape of handle.
The one thing I am learning is that I need to trust my instincts. For example: I felt that the clay I was using on Monday was too soft but I just kept on going regardless. As a result had a terrible morning of collapsed and wobbly pots and finished feeling totally demoralised. Later in the day I tried a different bag of clay with much better results. It’s times like these I have to remind myself that I’ve only been doing this for just over a year (with five months of no throwing) and that I can’t run before I can walk.
Hasn’t put me off yet though…
It’s been a while since my last post. Things have been pretty hectic here with the building work, and it is taking up all of my time. The good news is that construction is going well, a few small hiccups, but nothing major. The groundworks are pretty much complete so now the actual ‘building’ can commence. Also there is now an enormous hole in the garden ready for a retaining wall to be built. Once this has been completed the pad can be laid for my new studio.
I’ve been so busy that I’ve barely had any time for anything clay related. I’ve not thrown a pot for over five weeks and I’m really missing it. However I managed some sketching last week, and a bit of photography here and there. Even on a messy building site there’s inspiration…
Yesterday, with a certain amount of trepidation, I tried throwing with porcelain. I’ve read a lot about it being tricky to use, and it is. I don’t throw with a lot of water, but a number of times the pot I was throwing collapsed, because the walls had become too soft and I’d gone to thin for this particular clay. I’m going to persevere though as I’m sure I’ll get used to its idiosyncrasies. What I did love today was turning the surviving pots, burnishing them, and adding handles. In it’s leather hard state porcelain is amazing. It’s so fine and you can get it incredibly smooth. We’ll just have to see what happens when they’re fired.
I’ve been trying the porcelain because I want to find the right clays to commit to. Living where we do delivery costs are expensive so it makes sense to order large quantities. For the domestic ware I want something that fires white or very nearly white. I had high hopes of the extra white stoneware I’ve been using to date, but it’s been firing to a creamer colour than I had anticipated. Plus I’m having problems with speckles, probably caused by an increased level of iron in this particular batch. I’ve tried a porcelain/stoneware mix before, with good results, but it costs more than the stoneware. The porcelain does too, but with that comes increased strength and the possibility of translucency too. Hmmm.
I’d also hoped to use the same clay for both my domestic ware and raku pieces, but again what I’d originally been using doesn’t seem to be cutting the mustard, even though it worked fine when I used it at Grays. I’m going to trial some alternatives here too.
I’ll let you know how I get along, and post results when I can.
Sea urchin; straight from reduction (smoke) chamber (l) and after cleaning (r)
I thought I wouldn’t make it into the studio until next week but I got itchy fingers yesterday and couldn’t resist. I didn’t have time to throw anything so I decided to do some raku glazing and firing instead. It looked like it would be a perfect clear cold night for my second firing using the homemade kiln. I mixed up a new version of the turquoise raku glaze that I have used before – this time with a little less copper oxide in the hope for a lighter colour. I glazed a number of small urchins that were biscuit fired before the holidays. After trying to learn from my previous mistakes the results were much better than last time: a much quicker firing; and a better glaze colour; but nearly everything cracked again. Now I’m sure I need to change to a clay with more grog in it.
What I do love about raku firing is that at first you pull out these black lumps from the reduction chamber and they look pretty grim, but then you get them under the tap and start to scrub away the soot and smoke to reveal the finished pot beneath.
Next time I must remember some marshmallows for toasting.
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The last couple of days have been spent glazing and fettling my latest breakfast cups, small jugs and large dishes ready for Bertha’s first glaze firing. I’ve been trying out a number of techniques after receiving some really helpful comments and tips. My favourite approach so far was suggested by David Melville…
Fill the inside of the pot with glaze then straight away turn upside down and empty. With the pot still upturned immediately glaze the rim a little way down the outside. Leave overnight to dry. The following day dip the outside, with the pot the right way up and your hand/s pressed against the inside. Slightly overlap the earlier glazed rim. For me this seems to be cleaner than using tongs, with the least amount of drips that need to be cleaned up. Also by dipping the lip whilst the pot is still wet from glazing the inside only a thin layer adheres to the outside. Hopefully this will stop the thick glazed rims that I’ve been having problems with in the past.
I’ve just switched on the kiln so I’ll find out late tomorrow, or Thursday morning, how things have fared. I’ll post some pictures of the results.
It’s been another great week… busy but really good. I can’t believe that Christmas is only twelve days away. My children are getting extremely excited at the prospect, and so am I to be honest. However, my biggest milestone has been that finally Bertha was installed after two months of waiting. It was a struggle to find an electrician prepared to do the work, but Norrie came and saved the day. She was installed on Tuesday and I did a test firing that night. It was lovely just to switch on, set a program and let the kiln get on with it. I’ve learnt so much from firing Ruby but it is a relief to not have to continually manually increase the temperature throughout the firing.
Last night was the first bisque firing and all was well this afternoon when I opened up. It’s wonderful to have so much room – she has more than five times the capacity that Ruby does. Now I just need to get everything glazed and fired again by the end of next week.
I know for some of you this is your busiest time of year, but I hope you all have a chance to step back and enjoy it too.