Thursday 25 February 2016

More Bisque-Fired Organic Pieces

More pieces are coming out of the kiln now - a couple more bisque-fired pieces on the underwater/organic theme.

I've been making and building these pieces without much planning - for each one, taking a hump-moulded base and then working with its size and shape to create the final forms. It's been successful so far.

The first piece is based on anemone-type forms, the base had a flattened top which lent itself to having a different surface and texture to the sides. I used balls of clay on the top, flattened and then poked with a crochet needle. I'd seen surface forms like this on some corals. The end result is part sunflower, part anemone.

Anemone-1 at the drying stage
Anemone-1 at the drying stage

Anemone-1 bisque-fired
Anemone-1 bisque-fired
This piece has a hole so it can be wall-hung. It's about 20cm across and 12 cm high.

The second piece was much more of a surprise. I started off with a basic egg-shape formed from two moulded halves. I knew I wanted to create a form that had many fingers or tentacles all over it. What I didn't realise was that as I applied the tentacles to the form, it would change its shape as it was only part-dried. I think this made the final shape more interesting. The effect is part pine-cone, part pangolin, part coral.

Egg-coral at the drying stage
Egg-coral at the drying stage
Egg-coral - bisque-fired
Egg-coral - bisque-fired
I'm not sure on glazes yet. I am thinking of a plainer white glaze with oxide stain highlights for the anemone, and a plain blue or pink for the egg-coral.

Sunday 21 February 2016

New home, new studio and a fresh start

I knew it had been some time since I last wrote about the pieces I had been working on, but when I came face-to-face with my last blog post I was surprised to see that it was almost two years ago I last blogged here!

A lot has happened in those two years, we've moved home, I had to set up my studio from scratch, dealt with my studio space consistently flooding (we've had an especially wet year and our property is very exposed to the elements; wind, rain, sleet, salt air...

After a struggle to set myself back up again and to get going, some new work is finally coming out of the kiln.

My favourite finished piece is another inspired by scuba diving and has influences from the coral, anemones, sponges and sea-urchins I've photographed.
   It's a stoneware piece; hand-built, glazed simply with an opaque matt stoneware glaze, highlighted with copper oxide stain and antique pink glass. It's about 30cm (12 inches) across and I've purposely used stoneware so that this piece can be wall hung outside.

Greenware coral-inspired piece Greenware coral-inspired piece on my new whirler!
Greenware coral-inspired piece on my new whirler!
Greenware coral-inspired piece seen from above
Greenware coral-inspired piece seen from above
The basic shape for this piece is a dome, shaped using a negative plaster mould, the extra bits are.. ah well that's my secret! I rolled the clay slabs between pieces of sandpaper to attempt to give a grainy 'cellular' look to the tentacles, but the thick glaze made it impossible to see that in the final piece.

Bisque-fired coral-inspired piece with copper oxide stain accents
Bisque-fired coral-inspired piece with copper oxide stain accents
The tentacles retained their grainy texture during the biscuit firing. Here you can see the touches of copper oxide stain I've applied and its ready for the glaze to be poured over.

The glazed piece positioned in the kiln
The glazed piece positioned in the kiln
Once glazed, I used glass nippers to break fragments of antique pink glass and then put the shard of glass inside the tentacles, where they would melt into glass pools. The glaze I used was a ready-made powder from Potterycrafts - P2227, the test tile for which (with copper oxide stain) can be seen here.

I was pleased with the final piece. The thinner rolled slabs for the added tentacles, the new shapes and the subtle colouring of the glass contrasting with the stain gives it a more sophisticated look.

The finished piece - wall-hanging
The finished piece - wall-hanging
The finished piece - detail of melted glass
The finished piece - detail of melted glass
The finished piece
The finished piece

Tuesday 6 May 2014

Floral (dahlia) inspired stoneware garden pieces

And here are the finished fired pieces that I was glazing at the weekend. Unfortunately they are not good enough to be able to sell, some cracks and bits fallen off (which are disguised in the photos!) But they are good enough as prototypes now I have worked out the best way to build them so they hold up during the firing processes.

Here's the one with aqua-blue glass detail...

Ceramic stoneware floral decorative piece with aqua blue glass
Ceramic stoneware floral decorative piece with aqua blue glass
Ceramic stoneware floral decorative piece with aqua blue glass - detail
Ceramic stoneware floral decorative piece with aqua blue glass - detail
And the 'antique' pink one...

Ceramic stoneware floral decorative piece with pink glass
Ceramic stoneware floral decorative piece with pink glass
Ceramic stoneware floral decorative piece with pink glass - detail
Ceramic stoneware floral decorative piece with pink glass - detail
And finally here's some detail of the glaze - taken with my squidcam macro lens. The glaze reacts well with this clay and shows some of the buff colour and reacts with the iron(?) in the grog to give a speckled effect. It also shows a delicate crackle when seen close up.

Semi-opaque off white glaze on grogged crank clay
Semi-opaque off white glaze (Potterycrafts P227) on grogged crank clay


Monday 5 May 2014

Glazing floral inspired stoneware garden pieces

We're going to be moving house soon, which has given me the impetus to finish some of the pieces I have been working on so they are less delicate and more easily transportable. This also means I can photograph them and get them on my Etsy shop too.

I've had two large floral stoneware pieces hanging around in the 'in progress' shelf for some time now - no excuse for them not being finished other than laziness. So today I had a day to myself and prepared these to and some test tiles for a stoneware firing.

I'd previous glazed a similar earthenware piece in a shiny white glaze, but wasn't really happy with the finish. I knew I'd be able to glaze these two in a more subtle glaze.

Here's the first one (an identical form to the earthenware one) being glazed - pouring the glaze over it over a large bowl.

Glazing a stoneware floral piece with P2227
Glazing a stoneware floral piece with P2227
The glaze I am using is P2227 from Potterycrafts. This has a nice subtle semi-opaque off-white quality that works well with the glass. I'd used this before on a prototype piece but was keen to try it was a different glass colour.

Once the glaze has dried there is a lot of touching up to do by hand as the pouring method doesn't cover every part of the piece. Luckily the glaze is quite forgiving and tends to even itself out where application is not even, and will show interesting variations in opacity rather than highlighting drips and edges. After that is complete I upturn the piece and wipe excess glaze from the base before returning it upright and adding the glass. I use glass nibblers to cut pieces of glass from a sheet and drop them into the petals. During the firing the glass melts and flows so its not necessary to be too neat.

The second piece with  'antique' pink glass. The piece is more sunflower or daisy-like.

Glazed stoneware floral piece with pink glass highlights
Glazed stoneware floral piece with pink glass highlights
I've finally worked out that the easiest and safest way to get these into the kiln is to add the glass with the piece on the kiln shelf, so I can just lower each shelf into the kiln rather than handling the piece itself. Much easier!

Glazed stoneware floral piece with aqua-blue glass highlights
Glazed stoneware floral piece with aqua-blue glass highlights
There are being fired to:

  1. Up to 600ºc at 150ºc per hour
  2. 600ºc to 1260ºc at full ramp
  3. No soak
  4. Cool down
The kiln is cooling down right now but they will be out in the morning! Watch this space.

Sunday 4 May 2014

Ceramic herb markers - an easy process to repeat

Being my most popular item on my Etsy shop (not exactly a lot of competition there though) I decided to start producing these markers on a larger scale, and attempt to fire a whole kiln full in one go. So I got to work creating as many markers as I could to fill the kiln.

Here's the first six sets drying on a plaster bat.

Stoneware herb markers at 'leather hard' stage
Stoneware herb markers at 'leather hard' stage
Here's how I create the markers (mostly written for me to refer to in the future). I roll out the slab to a depth of 6mm, using wooden beading to get the correct thickness. Each marker is based on a 13cm long strip, which is cut using the width of the wooden beading (approx. 3cm). The tip of each marker is then cut to a point with a wet blade. I've found that the wet (clean) blade makes a much smoother and easier cut that a dry blade. I use an old kitchen knife for this. Oh and the clay I'm using is crank (stoneware) which is grogged and gives the markers a nice grainy rustic appearance.

I then use hot metal type to imprint the lettering. For these I use 48pt perpetua lowercase. I imprint the whole word (or as much as possible with one of each letter) in one go -  this keeps it a bit neater and stops individual letters being 'squashed out' by the next letter. I find that leaving the markers to part-dry on the plaster bat gives a cleaner and neater imprint. If the clay is too wet it can stick to the lettering, or even come off in the enclosed bits of the characters (e.g. in the 'o', 'p', 'b' etc.)

Once the markers are completely dry they are bisque fired:

  1. Up to 600ºc at 150ºc per hour
  2. From 600c to 950ºc at full ramp
  3. Cool down

With just four shelves in the kiln I managed to get thirteen sets of five markers in the kiln.

The next stage is to apply the stain to the lettering. For this I use copper oxide powder mixed with water, just a tiny amount to get the powder into a suspension so I can pick it up with a watercolour brush. I apply this to the indented lettering allowing it to pool in the letters but not worrying too much if it gets on the surface of the marker.

Here's what they look like at this stage

Stoneware herb markers - bisque fired with copper oxide stain applied
Stoneware herb markers - bisque fired with copper oxide stain applied
The next step is the wipe the excess oxide off the surface. This is best done with a moist (clean) sponge. The bisque fired clay will try to absorb the oxide, so its best to wipe this off with one clean stroke, I've found that pushing the sponge onto the surface to release a small amount of water 'pushes' the oxide into the lettering and then the rest wipes away easily.

Finally the glaze is applied. I've switched to using P2227 from Potterycrafts. It's semi-opaque and works well with the stain and also gives the clay a speckled 'oatmeal' appearance. I dip the upper side of each marker into a shallow tray of glaze, wait for it to dry then wipe any excess from the underside so it doesn't stick to the kiln shelf. This glaze doesn't run so you don't need to worry about leaving too much of a gap between the glaze and the bottom.

I place these directly on a (batt-washed) kiln shelf and fire them:
  1. Up to 600ºc at 150ºc per hour
  2. From 600c to 1260ºc at full ramp
  3. No soak
  4. Cool down
Results and photos of the finished markers in a follow-on blog post.

Saturday 19 April 2014

Throwing with porcelain - nine rice bowls - bisque fired

The latest batch of thrown porcelain bowls made it out of the kiln this weekend. And the results were pretty good.

Here are the nine surviving bowls dried to the 'greenware' stage. At this point I havent finished off the rims of the bowls so they look pretty rough.

Nine thrown porcelain bowls - greenware
Nine thrown porcelain bowls - greenware
Having smoothed the rims with my trusty fabric board, the bowls look a lot neater but still retain the quirkiness they get from being hand-thrown and all slightly (and some not-so-slightly) different.

Nine thrown porcelain bowls - greenware - with trimmed rims
Nine thrown porcelain bowls - greenware - with trimmed rims
I fired these to low bisque:

  1. 0°c to 600°c @max 150°c per hour
  2. 600c to 950c at full ramp
  3. Cool down.
And here's the results - nine porcelain bowls ready to be glazed. In the background you can see the fabric board used to finish the bowl rims.

Nine thrown porcelain bowls - bisque fired.

Tuesday 8 April 2014

Throwing with porcelain again - what a difference a lunch break makes!

A new batch (well just one bag actually) of porcelain arrived last week. I'm trying not to over-order on materials as we could be moving in the next couple of months. I've been working on a project to create some rice bowls for a friend, and its been a path of experimentation into unchartered territory with porcelain and crystalline glazes, but I've learned loads along the way. Anyway I digress...

The glaze is sorted, all I need is some well-formed bowls to put it on! As shown in my previous post, throwing is still an unpredictable event for me, especially with porcelain, which I actually now love throwing with.

I started this morning by experimenting with different weights of clay to get the perfect bowl size. I tried 400g, 350g and 300g. 350g seems about right to be able to get a bowl that fits into your hand comfortably.  So far so good.

I managed 9 bowls in one 90 minute session this morning, 10 minutes per bowl to prepare the clay and throw each one. Not bad.  Here's the results of the morning session...

9 small porcelain bowls, freshly thrown
9 small porcelain bowls, freshly thrown

Then I stopped for lunch. Things didn't go so well after lunch, no idea why, was I getting lazy complacent after throwing 8 good bowls in the morning?

Three bowls in the afternoon were so bad they went straight into the bucket.  One had a hole in the bottom but I kept it anyway. 12 passable bowls in all from a total of 150 mins work.

15 small thrown porcelain bowls, 11 acceptable standard
15 small thrown porcelain bowls, 11 acceptable standard