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Here is the completed piece all glazed up. All work has been done in the kiln, completed with satin glaze and minimal china painting. The only thing on him that isn't ceramic media are his mane flights which are enameled metal, inset with pins into tiny holes along his neck. Completed to a light dappled grey and with an optional base I have made for him to be affixed to, this piece will be posted to public auction. He measures 3.75" inches tall and will be a unique color and variety in an edition of not more than probably 20 or so variations. Once I have finished editing his photos and he has been sold at auction, I'll add a photo to my gallery album with him standing on his base. Tada! So now you know how I make my equine fine art sculpture in ceramics. This one earthenware but I also work in porcelain and fine bone china.

I wouldn't get your hopes up on that. We don't get iron staining from our water, and the iron impurities in my kaolins are guaranteed to be significantly higher than whatever might be in my water. Public testing results are under 0.03mg/l, so only trace amounts. We also know for a certainty that iron gives a yellow discolouration in oxidation whiteware bodies. There's a solid chance it is caused by something in my water, but I don't think iron makes sense as we'd see this in all bone china worldwide. Creeped your insta, my god your slip looks delicious, only way to describe it haha! That pink slip just looks amazing, luminous.

Wiping it down doesn’t seem to really help. I don’t think the vinegar is the problem. To answer your question though, I took an online workshop with Antoinette Badenhorst and she said that you should add a few tablespoons of vinegar to your throwing water if you are using porcelain because porcelain particles are very light and it will sink and separate. Using vinegar deflocculates the water and helps it stay in suspension. This is an excerpt from Ceramic Arts Network by Antoinette Badenhorst, “Adding a spoonful of vinegar in the throwing water gently deflocculates the clay.”

First, why vinegar in the throwing water? Usually when we see black on the wheel head it is simply a tiny bit of the aluminum abrading from the clay. Could just be the abrasion of the bat against the wheel. Does wiping it down not remove it?

I bought a brand new Shimpo Whisper VL in the middle of January. I have been using a bat system and have only really thrown porcelain on the wheel. I don’t clean the splash pan very often but I only use a bat when I throw. Yesterday while I was cleaning the wheel I noticed black stuff coming off the wheel and it feels abrasive. I don’t know what it is or how to get rid of it. I use porcelain so there is some vinegar in the throwing water but I didn’t think that would hurt anything and I usually have a bat on top so I don’t know why/what or how to get rid of it. Thanks

If we’re taking bets, I call iron in the water being the culprit. It’s the one constant variable across all OP’s tests so far. Very interested to see how the distilled water variation turns out.

@AndreaK I think you’re probably relatively local to me, so I assume we’re talking plainsman clay at least. Does the studio you’re looking at do commercial or homebrew glazes, and what kind of work are you thinking you’d like to make?

Ferric chloride isn’t necessary by any means. I haven’t done a whole lot of pit firing, but I did a couple back in college. You can get some lovely variations with terra sig on its own, especially if you’ve got a light and a dark colour to create contrast with.

Probably. Part of the fun of working with found materials is the variability. Sometimes close enough is all that’s needed.

When we produce a ceramic material that allows "light" to pass through that material we are working with a "glass" even though us potters call the material a clay body or a glaze. Todays "Ceramic-Tech-Today" article: Colored glass: From alchemy to empirical chemical design https://ceramics.org/ceramic-tech-today/education/colored-glass-from-alchemy-to-empirical-chemical-design/ has some useful information and background that might help determining why the bone-china pots show a color when seen in a light source. Remember that the source of the "light" is also an important variable. LT

It's my zero3 fritware clay, kiln is just a 40 litre rust bucket. I would go with the cone program as it may dynamically alter the firing depending on how it keeps up with the rate of climb. Do skutt controllers do that?

How fast did you fire it? Is it still sitting on the garage floor, if the floor is concrete you could have a uneven firing. The concrete is cold and will keep the bottom of the kiln colder. I understand that this is a small kiln, small kilns have to be set up correctly. I had one in front of a window but had to keep the window closed. It could really slow the firing and cool it down to fast. Small kilns already have a problem with fast cooling. Denice

After looking at the manual posted in the other thread this controller seems a bit weird. T1 is the time taken to get to the NEXT temperature not the C1 temperature. That seems backwards to any controller I have programmed. C1 0020c, T1 0030m C2 0100c, T2 0030m C3 0100c, T3 0600m C4 1140c T4 0100m C5 1240c T5 0000m C6 0020c That should go from room temp to 100c in 30min and hold at 100c for 30min. Then it takes 10 hours to get to 1140c (you could speed that part up) and then up to 1240c in 100m (60c/h)

Are you bisque firing first?

An image of the piece, err, pieces could help - character of the break, how thick/thin the ware, etc. What clay(s) are you using? About how long does it take to achieve 1240C? From peak, how long does it take to cool to room temperature?

It's not about temperature, it's about heatwork, which is what cones measure. Setting it at 950C doesn't necessarily mean cone 08. It depends on the rate of climb of the final 100C degrees. If it's not hitting the cone, then it could be due to the rate of the final ramp, or simply that the system needs to be calibrated. You can do a thermocouple offset which will affect all temperatures, or a cone offset to change the final temp of a specific cone. Using the pre-programmed firing schedule (I'd use Medium speed) will give you a better idea of how accurately the system is firing compared to a custom schedule.

Thanks for your reply. Not having any problems with the pots but rather feel that its not achieving the desired bisque of 950'C - trying to keep everything consistent so I know how the glazes will behave when applying and during the firing

Thanks for your message. I am going to try the preloaded cone 08 bisque firing next.

Thanks Neil, this was my next thing to try

That is a pretty low bisque...250°c/hr ìs very aggressive, what type of kiln is it? What clay body? I thought cone017 was for enamel work..

This is my first time firing my mug in a kiln (I use Mid fire clay) I used these segment: C1 (160c) 60min C2 (500c) skip C3 ( 1240c) 20 min C4 (room temperature) Each time I use my kiln my mug breaks Do you have any advice?

I tried firing it today at 1240c but my mug broke I put the Kiln in my garage and it is on a ceramic floor

I make terra sig regularly with my local clay and follow something similar to @Magnolia Mud Research’s post. I don’t go to great lengths to extract any remaining “finest particles” from the dregs. I played with that a bit but found it was counterproductive. Letting it slake a few hours then mixing it really well gets the all good stuff in suspension. I’m sure this is derived from Vince Pitelka or maybe Pete Pinnell, but it’s what I go with: 1 quart water to 1 pound of clay. 2.5 grams deflocculant per pound of clay. My deflocculant is half soda ash/half sodium silicate.

I came to the conclusion that low fire materials just didn't work for me for items needing to hold liquid..especially over time, and if given/sold to other people. It meant spending a fair amount of time (and a definate loss of money) learning how to make the chemistry/glaze ingredients/porosity etc. all working in conjunction. Mid-fire (or high) fire claybodies and glazes were way more likely to result in the desired maturity & glaze fit. I used low fire more for decorative ware that is not subject to freezing temps, no oven/microwave/grill, no liquids or wet food (like a tray for pretzels is OK) , or not something that will get lots of handling (depending on the object and it's purpose). ALso did a fair amount of reading, taking a course/class (today it is videos), to learn the basics before spending on trail & error.

I'm voting iron as well. I think that also accounts for the pinkish tint in low fire bisque pieces. If we were able to have a slab that thick of our clear glazes we would also see it to varying degrees. Window glass is also green for that reason. It look pretty darn clear when we look through it, but if you put some paint on it you'll see just how much color it really has. They make super clear glass, of course, but it's expensive. If I remember correctly they call it Water White glass. Standard plate glass and such is quite green. I worked for a glass shop for a few years after grad school, and we would occasionally have to replace opaque colored glass panels on buildings that were no longer available from the original supplier, so we just had to paint the backsides. Getting an accurate color match was nearly impossible due to the tinting effect of the green. You couldn't just have the paint color matched to the old panel.