PeterH

May be of interest, as it indicate that clay:water ratio and slip fluidly can -- to some extent -- be controlled independently.

Off topic, but as you seem to be exploring the boundaries at the moment so you may be interested. Historically millions of bowls have been made in bisque moulds. Not by casting, but by a skilled-labour intensive slow-wheel process akin to manual "jiggering". Also see https://www.youtube.com/watch?v=2Nef_LuFDkc Note there is no attempt to mould-form the foot or the upper smooth-section-with-rim. But you get a lot of texture with little per-pot effort, and the use of stamps minimises per-mould effort.

Not quite certain what you mean here. The 4-way switch diagram suggests this behaviour: Top-Switch=OFF - no top elements lit Top-Switch=LOW - both top elements lit (at 1/4 power) Top-Switch=MED - one of top elements lit Top-Switch=HIGH - both top elements lit Bottom-Switch=OFF - no bottom elements lit Bottom-Switch=LOW - both bottom elements lit (at 1/4 power) Bottom-Switch=MED - one of bottom elements lit Bottom-Switch=HIGH - both bottom elements lit What do you get? BTW If you have lost your neutral connection I suspect that both elements will be off for OFF/LOW/MED & both elements on for HIGH.

While waiting for an expert... Did the move involve any change to the power supply (cord, plug, socket)?

Related thread Kiln diagram on Paragon site https://eadn-wc04-7751283.nxedge.io/wp-content/uploads/A82WD.pdf Maybe each pair of elements is switched like this

My understanding that adding a glaze on top of a non-porous surface is a non-trivial task. Two area where this is commonly practised are bone-china and china-painting: both apply a low-fire glaze over a non-porous high-fire surface. ... note the quote Since the porcelain has zero porosity, getting a glaze to stick and dry on it is not easy, the process needed goes well beyond what a normal potter would be willing to do. China-painting relies on a wide range of "painterly" mediums, and is usually about applying painted decoration rather than flat-films. Of course, china-paints tend to be both opaque and non-food-safe -- I'm just talking about the technology. Painting with Overglazes https://ceramicartsnetwork.org/docs/default-source/uploadedfiles/wp-content/uploads/2018/02/chinapaintchapter5.pdf Oils and Mediums http://www.porcelainpainters.com/mediums.htm If you want to pursue to idea of glaze-on-glaze to render crackle finishes food-safe it might be better to start a new thread on the topic.

1) Wouldn't you need either a liquid or a very fine powder to get into the cracks? I've seen it suggested that the pigments in tube watercolours can fit the bill. One based on iron oxide seems an obvious starting point. I'd be inclined look for one where the manufacturers adverts show it dilutes well. .. or if you have a ball-mill. 2) I've also seen suggestions about using a non crazing glaze. First glaze firing to lower than maturity, which apparently can leave cracks. Stain with heat-proof pigment such as above. Second glaze firing to maturity, (partially?) sealing the glaze. From Ceramic Techniques, Pravoslav Rada p73 Crackles can be produced artificially by heating the pot and then sprinkling cold water on the surface. After crackle staining and refiring the coloured crackle pattern will remain coated with perfect glaze. The same effect can be achieved if a normal glaze is under-fired by 80-100C. Crackles produced by under-firing are then stained and the pot refired once again to the correct temperature. ... but getting a related primary and secondary crackle requires the secondary crackle to form under the influence of the primary crackle. Maybe you could apply the heat & cold water treatment twice? PS Re "inking" warm/hot pots (presumably <100C) to give more pronounced staining. Would the small temperature differences make much difference to the width of the crack? Maybe it would influence the viscosity of the ink more? PPS Haven't used them for years, but Kremer Pigments sell all sorts of exotic stuff. IIRC they have both European and American sites. https://shop.kremerpigments.com/us/ They have lots of iron oxide pigments, including: From the data sheets: Predominant particle size approx.. 5.8 μm ... another iron oxide pigment was Sieve residue (0.045-mm-sieve) (%) max 0.1 (0.045mm = 45 μm)

I remember seeing several "iron wire and golden thread" pots in the Percival David museum years ago, and they formed a lasting impression. A couple of weeks ago I noticed that a crackle pot that I probably made in the 1980s had developed a significant number secondary cracks. But these cracks only visible when looking hard from a foot or so. So I've been wondering if I should stain these secondary cracks with a brown "Indian ink". Although I'm not certain that the primary cracks are bold enough to give a good end result. PS From p585 of Ceramic Technology by Rose Kerr and Nigel Wood (Volume 5 part 12 of https://en.wikipedia.org/wiki/Science_and_Civilisation_in_China) Perhaps the best evidence for the contemporary appreciation of crazing in Kuan and Ko ware is the occasional practice of staining the major glaze-crackle with an intense black pigment to provide a network of fine black lines on a smooth light ground. By necessity, this would have happened soon after the firing, and most probably when the wares were still hot from the kiln, when the craze lines were relatively open. Ceramics can continue to craze for days, or even for years, after firing,and this secondary crazing system often appears as a finer network on Kuan wares, between the major crackle lines. This secondary crazing is often stained a lighter colour, perhaps deliberately or perhaps simply through use. These two crazing systems supplied the celebrated "gold thread and iron wire" effect, so often admired in Kuan and Ko wares. How the fashion for staining the crackle began is not known,but one possibility is that it was first used as a `rescue' process, designed to improve the appearance of accidentally oxidised pieces.

You might find something of interest in these. In the Studio: Supersizing Clay Bodies https://ceramicartsnetwork.org/pottery-making-illustrated/pottery-making-illustrated-article/In-the-Studio-Supersizing-Clay-Bodies# Additions to clay bodies (sampler) https://www.yumpu.com/en/document/read/19109768/download-a-free-excerpt-ceramic-arts-daily Grog https://digitalfire.com/material/grog

Just to point out that there has been some uncertainty over the amount of SiC in some recipes 0.34% or 3.4% . ... BTW Akiko’s Crater is another lava glaze in glazy.org PS In case you were wondering, some of the literature on SiC-reduced copper reds suggests that SiC outgasses when the glaze it is in contact with melts, rather than at a specific temperature.

+1 ... but I failed to find the extract on cracks. In case it isn't just my finger trouble, here is an extract from an earlier posting http://ceramicsfieldguide.org/pdf/materials-handouts/ClayCracks.pdf

https://www.potterycrafts.co.uk/Products/pottery-powdered-clays/P3103 Deflocculants are added in the spray drying of this clay so it is not necessary to add them.

I'd hoped that one of the experts would have commented by now. Looking your pictures. Is the one on the left a casting of the water glass, and the one on the right a casting of the espresso cup? Do you have any idea why the two surfaces look so different. Did you do anything differently when making the casts or the moulds. Looking at the first picture. The inside is very uneven and I've no idea why, so I'll just mention a few possibilities ... Defective slip? - Was the slip nice and uniformly smooth: as it went into the mould and as it came out. No lumps or uneven "thickness" or jelling. Defective mould? - Did you buy it or make it yourself. Defective plaster? - What plaster did you use, and what was the ratio of plaster to water Contaminated surface? - Did you use a parting agent when you cast the mould. Damp mould? - How did you dry the mould after making it. How long did you dry it for. Outside OK? - Can you confirm that the outside of the casting is smooth and uniform. PS I wouldn't change your slip until you have some idea why the two castings came out so very differently.

Changing the mesh size of the silicon carbide apparently influences the appearance. PS I suspect that refiring can only smooth/collapse/consolidate previously fired lava glazes, as all their fizz was expended in their first firing. As the top half of the cylinders indicate thicker application of the glaze increases the foaming -- especially for finer grades of SiC.

Can you confirm your slip recipe. Potterycrafts gives 18.5 litre of water to 50 Kg powdered clay (i.e. 0.37 litre water to 1 Kg powdered clay). https://www.potterycrafts.co.uk/Products/pottery-powdered-clays/P3103 Walkers give 9 to 12 litres water to 25 Kg powdered clay (i.e. 0.36 to 0.48 litres of water to 1 Kg powdered clay) https://shop.walkerceramics.com.au/AW500.B/Limoges-PC010B(CM10)-Porcelain-~25kg/pd.php Can you confirm that you didn't use freshly-made casting slip, as it takes a while to fully hydrate the clay (e.g. overnight).

Any help? https://cdn.shopify.com/s/files/1/0272/1968/9606/files/KS1227_KS1027_And_KS1018_1PH_Wiring_Diagram.pdf?v=1593295124 At a quick glance all the switches seem to have similar wiring

Perhaps this video, which you mentioned in an earlier posting. http://mcgyakimono.blogspot.com/2010/08/making-teaware.html PS Thanks for so many memorable postings.

I expect you are right that it doesn't contain any "smarts" for minimising the effect of failing elements. PS What information I found (but haven't read in detail) I think that the CE is just an indication is passes European community standards CE marking for Electronic equipment - EMC testing So your controller is probably a Stafford ST316B. Data sheet, installation guide and user guide at https://staffordinstruments.co.uk/st316b-controller/ Site https://staffordinstruments.co.uk/ Contact https://staffordinstruments.co.uk/contact-us/

Do you want/need the inside of the tube glazed? Would some sort of bellows help you blow out the glaze -- e.g. an air-filed glaze trailer. Pipe cleaners, or a more durable equivalent such as: 5 x Straw Cleaning Pipe Cleaners kit, Bristle Metal Pipe Cleaner for Drinking Straws, easy to brush and clean pipes, Pipe Cleaner Kit, Straw Cleaner Brush and kit for craft supplies https://tinyurl.com/5ftme7n7

Assuming the damp box started out with water in it, it could simply be a magnified form of efflorescence of some soluble salt as the water seeped into the pot and then evaporated from it..

If the problem is the copper carbonate out-gassing have you tried black copper oxide? Found a cone 6 switch, and the colour seems to be unchanged. Switching copper carbonate for copper oxide in a fluid glaze ... in Copper Oxide Black https://digitalfire.com/material/copper+oxide+black Surprisingly, the bubbling also seemed unchanged. For this base glaze and firing schedule Tony Hansen concluded: The copper oxide recipe is not bubbling any less even though copper oxide does not gas. The bubbles must be coming from the kaolin.

Useful reference Amps vs. Volts vs. Watts vs. Ohms: What’s the Difference? https://www.familyhandyman.com/article/electrical-terms-explained-watts-volts-amps-ohms-diy/ ... with a good summary

IIRC I've seen blue/green "copper" recipes with a little cobalt, and vice versa. Presumably it simplifies the final optimisation of the colour. PS loosely related ... which include a set of copper vs cobalt test tiles (for a specific base glaze)

Are you talking about this sort of process? Hammock Crockery Molds The Catenary Pottery Printer Produces Bowls in Sagging Fabric https://www.trendhunter.com/trends/catenary-pottery-printer More photos of the pots in https://design-milk.com/innovative-catenary-pottery-printer-gt2p/ PS I have a very vague memory of somebody else who made very large very shallow circular vessels this way, without the hype (or the mime artists). They used a very taut mesh, and had no noticeable undulation at the rim.

At least for initial experiments it might be worth using a found or bought texture-mat/texture-roller for producing "test tiles" and then to help produce a master to make a mould from. Please let us know how you get on.