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It seemed like a given that they can and many of us do this but I reached out to the Ceramic Shop to ask them specifically. They make, sell and wholesale posts to other ceramic suppliers in the US and elsewhere. (they make triangular and square ones) Their reply: "Thanks for reaching out! To my knowledge, yes, they can be used on their sides. Kiln posts are made to be the most stable on their top ad bottom though and they will take up extra room in the kiln on their side. If you need a smaller kiln post for some works you can check these out: https://www.theceramicshop.com/product/148/kiln-post-1/ All of our kiln posts are rated to cone 10. Best, Syd"

Hi and welcome to the forum. Somewhere to start might be looking at Terra Sig with added materials such as salt, soda ash, oxides and stain and borax. Washes would be another avenue to experiment with. . Also have a look at Mary Fox’s work where she uses lithium carb plus copper for a dry surface. (on some of her lowfire sculptural work) This articles from Pottery Making Illustrated might be a good place to start for alternative surfaces. It’s behind a paywall but you can access 3 free articles a month. https://ceramicartsnetwork.org/pottery-making-illustrated/pottery-making-illustrated-article/In-the-Studio-Washes-and-Patinas# Perry’s wash recipes are for cone 10, for lower firing adding flux would probably be necessary for some of them. Also, firing in oxidation rather than reduction will make a difference with some of them. http://shambhalapottery.blogspot.com/2013/03/happy-st-paddys-day.html Pit firing would be another avenue to explore.

From the Kanthal website, they recommend an oxidation firing to 1050C / 1922F for 7 to 10 hours. I'm thinking the people who hold for 7 to 10 hours are going to be few and far between if they mean a hold at 1922F and not a slow rise up to this temp. I typically hold for 3 when replacing elements. I don't know anybody who does a re-oxidation of the heating elements. I guess they are talking about a repeat empty kiln firing? edit: Euclids recommends holding for "several" hours also. "To protect elements used under these conditions there is an element conditioning process that is desirable for FeCrAl elements, which requires heating the elements, in air, above 1830oF/1000oC, and holding for several hours. This develops an aluminum oxide coating on the outer element surface, which can dramatically improve element life.https://www.kanthal.com/en/knowledge-hub/heating-material-knowledge/operating-life-and-maximum-permissible-temperature/ "In such cases Kanthal® alloys are recommended, provided the heating elements are pre-oxidized in air at 1050°C for 7–10 hours. Reoxidation of the heating elements should be carried out at regular intervals."

There is an old thread linked below where a few different methods are used, including tattoo ink and china paints.

It does look like a crawl/reticulated glaze but I think the tricky part would be how they got it to stay on the pot on the undercut vertical surfaces. 100 Grand maybe?

Another thing that works for rims instead of a piece of chamois is the microfibre cleaning cloth that comes with eye glasses. They last a long time and don't go slimy at all. Wire coat hanger corners to make callipers.

@s6x, could you post who the maker is?

I've altered the Studio White to remove the Gerstley Borate and supply the boron with frits instead. I've also removed the Minspar 200, I did this because I wanted to get some clay into the recipe and the original only had 2 bentonite and zero epk, most of the sodium and potassium is now supplied by a frit. I replaced the calcium carbonate / whiting with wollastonite for two reasons, firstly it melts better than whiting + silica and secondly it has less loss on ignition. I kept the oxides the same in the formula, they are just being supplied from different materials. My hunch is it will melt more than the original. Kept the same flux ratio and reduced the LOI. Because of all the frit this glaze should have 2 main melting zones, lower temp for the frits to get started melting and then higher temp for the zinc. (put the epk in your mixing container first so the frits don't just stick to the bottom) For the Wollastonite Clear I used 3 frits, I kept the boron level high. I wanted to reduce the silica and alumina amounts plus raise the silica above a 1:10 alumina : silica ratio. I reduced the sodium and potassium and increased the magnesium. By reducing the alumina and silica this version should be more fluid than the original, it did raise the COE slightly though. Overall the Wollastonite Clear should make a more durable glaze than the Studio White. I didn't add tin to any of the recipes, wanted to see the numbers without it. (use 325 mesh silica) Please ask if you have any questions about why I subbed what I did if you are unsure of anything. (as always please test a small amount of the altered versions, what looks okay on paper doesn't always translate to a pot) edit: "I'll do a full cone 6 fire on a small bowl as soon as I bisque some test bowls." +1

I would keep the kaolins, can sub those quite easily in glaze recipes. Calcined kaolin I would keep, use it as part of the kaolin in any glazes that crawl due to high kaolin amounts. (have to recalc the amount used to sub for un-calcined kaolin) Alumina oxide can be used in place of alumina hydrate in kiln wash (use 1/3 less by weight). If anyone uses washes then the Barnard, Burnt Sienna and Umber can be used in those if they want dark/earthy colours. Kona (F4) can be subbed for Minspar 200 in a 1:1 ratio. Tennessee Ball comes in different forms, given how inexpensive ball clay is I would donate that one if you don't know which you have. Fireclay, Sagger clay and mullite, unless someone is making their own bodies I'ld donate those. Redart can be used in bodies and glazes. Silica sand, might be useful if someone is firing large heavy pieces or wants to wedge into their clay but if nobodies used it for years maybe not worth keeping. CMC gum, mostly used for making brushing glazes or hardening a dusty glaze. Calcium Carb precipitated, this is just whiting/calcium carb, keep it. Black Iron Oxide, can be used in glazes, need to compare the iron content with whichever red iron oxide you are using to sub it. It doesn't create the red staining mess that red iron oxide does.

Firing to a full cone 6 is worth doing. This might just be enough to rid the glaze of the dimples. I'll rework the recipes so you have an early melting one and a late melting one, this way if the glaze is sealing off the clay before it's finished offgassing there might be a difference in how well they heal over the pinholes. I'll use the Studio White as the base for a late melting one, zinc melts later in the fire and as it's an auxillary flux in the Studio White it might work to do a modified version of that one. Downside is zinc itself can create problems with pinholes so it might be counterproductive. What is it about the Studio White that you don't care for it as much as Wollastonite Clear? If you have any flat test pieces you could use as tests I would use them, pinholes are harder to fix on flat surfaces.

If the dimples are from unhealed pinholes then it's logical to think that giving the glaze more heatwork will smooth them out. It's interesting that the refired bowl smoothed out the pinholes and the clay didn't bloat. What happened when you fired the Wollastonite Clear to a full cone 6, was the clay bloating or had a higher absorption? At ^7 you had increased absorption, correct? Common fix to make the glaze more fluid would be to remove some alumina and silica but keep the alumina:silica ratio above 1:10 but that's going to mess with your COE and you might then get crazing which in turn would need some of the higher expansion sodium and potassium being replaced with a lower expansion flux such as additional magnesium or lithia, at this point so much tinkering will have been done that it will basically be a different glaze. I can alter your recipe to do this if you want to give it a go. Do you have Ferro 3110? Do you have the recipe for the Studio White? Have you noticed if different thicknesses of the Wollastonite Clear results in more or less pinholes/blisters? I also think the pinhole issue is from the claybody but understand you are invested in using this body for now so it looks like glaze formula + firing + glaze fluidity + glaze thickness are all going to play into trying to overcome it.

Yes to both questions. I would suggest just putting that 5 gallon bucket of glaze to one side for now without trying to adjust it. Make up some slip with your claybody and try that with your colouring oxides or stains. Your altered glaze might be just fine the way it is.

Have you tried the Rutile Green base with 5 tin (and no rutile or copper)?

Is it shivering on rims that don't have the white slip? I'm wondering if the slip is shelling off the pot on the rims and taking the glaze with it. Have you used this slip with the original dolomite version of the glaze successfully? Any chance you have a piece you could put in the glaze fire with the slip but without any glaze on it? I had a look at the formulas for the dolomite version compared to the bone ash + talc version, while there are differences they are not a world apart. There is a fair bit more silica in the bone ash + talc could explain the glossiness.

This is going to be a long shot. Recipe?

I would put furniture in. I think it is the clay. Hoping a more fluid glaze will fill the pinholes but might not be enough. Plates are going to be the litmus test as there isn't gravity to help. I have a newer bag of wollastonite that isn't as agglomerated since I wrote that I needed to whiz it in a blender, now I just add an extra little bit extra when I'm weighing out the materials to compensate for what is left in the sieve. My bucket top up batches have 985 grams of wollastonite, so I bump this up to 995 when weighing it out.

The talc is going to have a lower COE than the dolomite, that might be it? Do you have a big bucket of it?

@Marilyn T, you could shorten the bisque schedule for typical domestic ware pots. Have a look at Steve Davis's schedule for problematic clay. Note the slowing down during carbon (both organic and inorganic) and sulphur burnoffs. (It's behind a paywall but you can access 3 free articles a month) Skip the length candling if your greenware is bone dry, shorten it to an hour or two if not. I usually warm the kiln up to 220F in the evening then shut it off and let the pots sit overnight in the kiln then start it up in the morning. Davis schedule is really slow, but still faster than the Clement one. https://ceramicartsnetwork.org/daily/article/A-Bisque-Firing-Schedule-to-Help-Prevent-Glaze-Faults

If nobody here has used that glaze maybe it's worthwhile contacting him and asking about it. Just looking at the materials it's going to be an opacified calcium alumina semi matte. Calcium tends to bleach out iron a bit. I'm sure you already know this but some people think zinc in a reduction firing helps get the melt started but then given it's volitility is gone by the end of the firing. Your dolomite glaze shivered? Pat Horsley's website and contact form here.

Making the glaze more fluid might work but before trying that I'ld give the other firing schedule a try. Having a longer time leading up to the higher temperature might be enough. edit: if you want to try a more fluid glaze at the same time this might be worth testing. It is a lower expansion than your Wollastonite Clear though. I kept it to materials you already have. ^6 Test White - fluid Ferro Frit 3134 - 34 Silica (325 mesh) -27.5 EPK - 16 Amtalc - 12.5 Nepheline Syenite - 10 total 100 Tin Oxide - 5

Hi and welcome to the forum. Crazing means the glaze doesn't fit the claybody it's on. A simple analogy would be a pair of jeans a few sizes too small for someone, they are going to stretch and rip. This is what your glaze is doing on the clay. It has nothing to do with taking them from the kiln at 100F and firing cooler will just make it worse. Since it's a commercial glaze the simplest thing to do is ask your supplier or Laguna Clay which body they recommend for this glaze. It is hard to see crazing with some glazes, try rubbing a permanent marker or calligraphy ink over the glaze then wiping it off, the crazing should be visible then.

Okay, correct me if I got any of this wrong: Lower top temp + 5 min soak = more pinholes. You are dropping to 2040F then soaking for 20 = best results so far Bisque schedule looks great. Pinholes look they could very well be from clay contaminates that haven't burned out in bisque. I would suggest dropping your top temperature to something in the range of 2165F, or enter ^5 for your peak, then add a 18 minute soak, this should get you close to cone 6. Then I would drop to 2085 and do another soak, this one for 12 minutes. If the glaze does not need a slow cool to develop the visual texture, ie it's a gloss glaze with no streaking / variation then I would shut if off then. If it, or other glazes in same firing, need a slow cool below 2085 then follow your regular downfiring schedule. This suggestion is just somewhere to start, do your usual cones, see what this schedule gets them to and just try a piece or two to see what happens. I'ld also suggest adding a bit of thickish dry glaze paste (the stuff from around the edge of the bucket) to the pinholes and stick the pot back in the kiln for another firing, see if the pinholes heal over or get worse. (put this pot in the coolest part of the kiln) I know how frustrating it can be to fire a kiln nearly empty (apart from the typical number of shelves also in the kiln) but it saves tossing a load of pots with pinholes. Did the other glazes, including Studio White result in pinholes also?

Really good information Marilyn, thank you for such a comprehensive post. I'm not seeing anything really glaringly off with the recipe or the glaze firing. Glaze recipe looks like it would make a very durable glaze. I haven't used that claybody but I'm wondering if how it's bisque fired might be part of the problem. Is your kiln vented and do you really cram the bisque firing full? How fast do you bisque fire to 04, using a preprogrammed schedule? Do you have a closeup of a couple of the pinholes?

@Marilyn T, could you post the recipe, glaze specific gravity and which clay you are using? Also, does firing to 2185/2190F bring cone 6 down in your kiln? No soak at peak temp?

Another thing you can do to toughen up unfired glazed pots is spray them with laundry starch. (the aerosol kind, not the spritzer bottle)