Callie Beller Diesel

I’ve used dry cleaner plastic for years and had no problems with it. I don’t like the marks that shopping bags leave. But I think it’s just a matter of personal preference. They’re both plastic. They both work.

You might want to consider cargo space if you know you want to use a vehicle to do a lot of markets. Keep an eye on that number when shopping. Heated seats are nice and all, but if your vehicle is a PIA to pack, it’s just going to cause stress. You don’t mention the model of the mom wagon, but the Mercedes model E All Terrain has a listed cargo capacity of between 640 and 1800 L (ish), or about 22-63 cu ft for the Imperial users. My Pacifica has 32.3 cu ft just behind the third seat, and if I fold down both rows of seating, I can get 140 (ish) sq ft. My setup is very lightweight and compact, and because my 4 day sales are all indoor ones, I don’t need to pack a canopy. I have full use of my rear view mirror. I have some friends who initially bought a crossover, thinking that they didn’t really want a full sized SUV but wanted the packing space for doing markets. They found it to be quite cramped and difficult to pack, especially when you don’t have the patience to Tetris everything perfectly after 4 days of selling. They wished they’d gotten something with more cargo space, and I believe they did go with something larger when it came time to purchase their next vehicle.

@PeterHfrom that same wiki, “A 1.0 M solution (about the concentration of domestic vinegar) …” So if domestic vinegar is somewhere between 5 (regular white vinegar) and 7% (pickling vinegar) by volume, then 3 M vinegar would be between 15 and 21%. Very unscientific calculation there, but perhaps close enough for these purposes. In what I thought was a rather spectacular example of greenwashing, you can get Eco Living Solutions brand 25% industrial grade acetic acid on that South American River website. 45 and 75% also appeared to be available in different brands, I just thought the marketing on that one was hilarious.

I remember that thread! It was a pretty cool one. It’s interesting that Tony Hanson was pursuing a similar series of testing about the same time, seeking a really clear cone 6 fluid melt glaze. He kept going, doing a major update to his findings in 2019, and continues to add notes to the file. He took a slightly different tack than you, in that he was less focused on the silica beyond particle size as it contributed to melt, and wanted to embrace a multi flux approach for durability since his approach is based in making functional pottery. He did achieve a number of good results, and continued with the work to reduce COE values so it would fit a particular nuisance porcelain Plainsman makes. This is the link to phase 2 of his testing, which involved really eliminating bubbles and maintaining colour response. The links to phase 1 and 3 are at the top of the page. I noticed in your original thread there were some mentions of using fining agents to get rid of seed in glass, and that you were using a red clay for some of your Currie blends. Iron is a fining agent in glaze, and if your aim is to create a clear glaze over a red clay, using an amber instead of a clear can be a solution. Reducing the high LOI ingredients and fine tuning your firing seems like the majority of the process, but if there’s remaining bubbles they might need that extra kick to evict them.

I think success is relative. I’m seeing a lot of good possibilities in those tests, depending on how someone might want the final piece to look. Test tiles are just neutral information. It’s not really useful to see them in terms of right and wrong for all people in circumstances, but more in terms of right or wrong for you in your current circumstances. And what you like or are trying to achieve is also subject to change. Glazing can be really frustrating, because you can’t see the immediate results like you can with paint, and because you really can’t get away from some testing, even with commercial glazes. So then the question is, what look are you trying to create? The two samples you mention show a lot of variegation and visual texture. Those things can be affected by different application techniques, and varying the kiln firing. If you’re not firing your own kiln, you’ll have to play around with application first. Changing the order in which the glazes are applied can make a big difference in appearance, as can the thickness of the layers. Some of those flatter samples like Arctic blue over texurizer showed a heavier application of the blue, and the texturizer was partially sponged off. There’s some evidence of variation starting, so that suggests if you want more, start by either reversing the application order, or not wiping down the texture. If you like that variegated look, another layering glaze you could look into is one of the ones they call flux

Crazing has very little to do with your cool down rate. If you slow your cool and it appears to get rid of a crazing problem, you’ve likely only caused a crazing delay. A shock test will still bring it out. Crazing is caused by COE values that differ too greatly between clay and glaze. If this is your first test of using Frost instead of the Standard 365 clay and all your usual glazes have crazed, that just means the 2 clays have different COE’s. That’s not unusual at all. If you want to keep using the same glazes, you’ll have to adjust them all to compensate. If the crazing is slow to emerge and the crack pattern is a larger one rather than a covering of fine lines, chances are the glazes won’t need a lot of adjusting. That which bodes well for keeping the character of the glazes intact. It’ll be a little bit of work with a test sieve to hone in 10 glazes, but it’s doable. If you’re going to use glaze software to help narrow the project down, some notes about comparing COE values: 1) Using calculated COE values won’t eliminate physical testing, but it’ll cut down the work and materials used. 2) COE values aren’t absolute numbers. They’re only a snapshot of a measurement taken under a very specific set of circumstances. If you change the circumstances, you get a different value. They’re good if you’re adjusting a glaze without adding or removing any ingredients, only changing quantities. Also worth noting that because of this, different glaze softwares use slightly different COE values in their source tables. If you’re looking at a clay manufacturer’s suggested COE range for glazes, make sure you’re using the same software they are. Many manufacturers have stopped offering these suggestions though, because they tend to cause more confusion than they help with. 3) You don’t want to match coe values of your glazes to your clay. That results in more glaze flaws. Knowing that you need to move your existing glaze COE values higher or lower is the important bit here.

@High Bridge Pottery, I don’t know about the UK, but HCl is used here to etch concrete for painting. I can get it at Canadian Tire, so maybe check DIY friendly stores?

The sticker shock on a tiny 5 ml bottle of gold lustre is real. But. I was amazed at how far the bottle goes. You do get good value out of it, especially if you’re selling pieces. I have used a metallic pigment mixed into an acrylic base, similar to the link you posted. I put it on some Christmas ornaments and it wasn’t bad, but it doesn’t read the same as gold lustre. It reads like a gold nail polish.

Since sanding is so time consuming, trimming on the surfaces you can reach will eliminate that portion of it. The fewer times you have to touch a piece, the more efficiently you can work. How important to you is it to show off the entire surface of the piece? For things like mugs where you’ve said trimming is impractical, would a slightly tinted or opaque liner glaze that hides an unsanded surface be an acceptable design choice for you? It might not work for everything, but could be another time saving solution.

If you’re finding your plaster slabs are saturated and you’re in a humid area (England, ahem), put your slabs next to your kiln when it fires to take advantage of the heat.

@oldlady, I will add a few tags to this post so it’ll show up in search.

Can confirm that is black coring. A fast glaze cycle isn’t great for bisquing most clay bodies, red ones in particular. I think that this is pretty strong evidence for going too fast through quartz inversion and excess free silica being your cracking source. If you look through the digitalfire articles, especially the ones on black coring, bloating and clay testing, you’ll find a lot of really helpful info on how to proceed. There’s a really interesting note in the black coring article with some observations about red clays and feldspars making strong high fire stonewares. This could be a really nice clay to add to a clay body to give it some character. It seems to need some feldspar.

Refiring cone 6 items usually gets tricky when the underfired piece got close to the intended temperature range the first round. Accumulated heat work is going to matter less if the pieces only got to bisque temps.

Babs makes a good point. If you haven’t made this piece, I wouldn’t attempt it. You don’t know what temperature the clay or glaze matures at. If you don’t know exactly what glaze was used, the one you apply could create a eutectic with the existing glaze, making both run a lot more than they would by themselves. If the piece was originally fired at cone 6, refiring it to low fire temperatures may partially re-melt the existing glaze, making it do all kinds of ugly things.

Regarding the overall response here: we’ve had a LOT of folks over the past few years ask about how to achieve a similar aesthetic as in the pictures you’ve posted. Most beginners don’t realize the look can either achieved with photography edits by someone who is both a good potter and photographer, or with poorly fired/impractical ware made by someone who is taking accurate pictures. Without holding the pots in question, it can be hard to spot the difference. When someone doesn’t know badly fired ware is a possibility, they have no reason to think to look. Glazes that are dry matte can be made through a number of mechanisms, some of which are great for sculptural work, but aren’t durable enough long term to use on kitchen dishes. However some glazes that have a satin finish are extremely durable and ideal for functional use. You can’t tell which is which without looking at the glaze recipe in software or knowing firing temperature though. A glaze that is very dry to the touch is often underfired though, and falls into that first category. If you don’t have a lot of glaze chemistry knowledge and are making pots for yourself and not for sale, using a commercial product that is designed for the purpose is an ideal solution, and will save you a lot of work. If you do want to mix your own glazes, you want to make sure your glaze is fired to maturity and formulated properly and involves a bit more testing. You’ve got some good starting points here, and we always appreciate updates!

If they were just slipcasting and glazes weren’t involved, most clay-based hazards involve inhaled silica, and can be easily remediated with a lot of wet cleanup. A proper respirator is still a must though, because even wet cleanup will stir some things into the air. If there were glazes, possibly lead, involved, we’d need more info. I like Bab’s suggestion about having a cleaning stipulation before move in. edited to add: I’m going to take the liberty of deleting your duplicate post. You probably want all the information in one spot.

Hi and welcome to the forum! We do have a small pinned thread started in the glaze and chemistry section with a few links on working with wild/found/native clays, and you can start there, but I know not everything we have on the forum is in that thread, so I encourage you to do a search from the main page with some of those terms. Others have shared information before. Definitely go through the testing mentioned on Digitalfire listed here, including checking out the article links at the bottom of the page. Characterizing your clay can help a lot with figuring out why it’s doing what it’s doing and will give you hints about its composition. Checking with your local geological survey can also give you an idea of what the clay’s composition might be, which will give you more info on working properties. According to the Potter’s Dictionary of Clay and Glazes by Hamer and Hamer, the cracking pattern of your jug is consistent with bisque dunting. They state that bisque dunting either happens when the firing cools too quickly through quartz inversion, or possibly from being not fired enough to achieve enough strength. Are your jug shards really soft and crumbly? If the speed of the firing is a problem, that could indicate the clay is very high in free silica. If the dunting is an indication of the bisque not being hot enough for strength but you get some pretty extreme bloating only 3 cones hotter, that’s a very narrow firing range. If you want to use this clay, it’s definitely going to have to be amended. Hamer and Hamer suggest fixing dunting due to to free silica by binding the silica up by adding a flux like feldspar. Given that feldspar can also contain a lot of alumina, that might be a place to start. It could also be you need to use this clay as an ingredient in a more balanced clay recipe, or turn it into a more vitreous decorating slip with a bit of flux.

Just for reference, the Archie Bray has their kiln firing costs listed here, and their largest gas kiln, the Bailey that has a stacking volume of 110 cu ft has a stacking space measuring 48” x 60” x 66”. Closer to 5 feet than 6. Montana isn’t super close to Seattle, but it’s not an unreasonable distance.

@yams23 are you thinking you want some form of regular studio membership, a workshop/residency type situation for a small run of pieces, or a kiln-for-hire for a one off? A 6 foot diameter kiln is a tall order, pun not intended but I’m owning it anyways. I can’t even think of industrial settings where a gas kiln would be 6’ wide, even if there are some gas car or conveyor belt kilns that go that deep. There are technical issues in heating a space that large, and the shape of the space plays a big role. The 2 better solutions I can think of are to either find the largest kiln available to you and build your pieces to fit that, perhaps in modules that can be assembled later. Alternately, if the piece doesn’t need to be fired to a particularly hot temperature, you could possibly build a fibre kiln around it and fire the piece in situ.

I definitely recommend working a half day into your schedule to document new work if you can. My photo set up is in between my kiln and where I pack pots for shows. They come out of the kiln, into the kitchen for quick pics, and into bins. The more lead time you can grant yourself the lower the stress levels.

I’d want a slipcasting expert to chime in over me, but calcium is less soluble as temperature increases. Thus kettle scale. So it’s not an unreasonable thought.

Because I do spend an unhealthy amount of time on instagram, I sleuthed around all 3 accounts a bit more, to see if I could figure out exactly what was going on there. All of the accounts you linked to are using assorted speckled clays, not a plain clay with a speckled glaze. Find images and carousels where you can see the fired foot rings of the pots, and you’ll see the evidence. The speckled look comes from either manganese or iron impurities in the clay body, depending on whether they’re firing in an electric or gas kiln respectively. Also, the images you’ve chosen to link all appear to be very matte due to moody lighting, but product listings of the same items on their websites show the work more clearly. All the glazes on all the functional pieces are a satin or gloss. Most notably, the “balance” cup is remarkably more glossy on the artist’s website than in the image posted here. Get a speckled clay body and use the glaze Bill linked, and you should get your desired effect. Edited to add links to the respective artist’s websites: @annemiekebootsceramics: https://www.annemiekebootsceramics.nl/work/tableware @sensitiveboi: https://cargocollective.com/sensitiveboy/index @darc.matter.ceramics https://www.darcmatter.eu/shop/alle-items

As someone who learned patience very much against their will, moaning about it the ENTIRE time: this will only get you so far. At some point someone’s going to make a nasty comment, and the good feelings of cranking stuff out will vanish very abruptly. There is a happy medium between waiting 4 days for leather hard and speed drying in your oven in a matter of hours. It leads to better pots, and all the good feelings about having learned a skill/accomplished what you set out to do on purpose, rather than accepting “happy accidents” all the time.

Hi and welcome to the forum Carol! What do you need advice in regards to?

I keep my kiln shelves (electric) outside in a tin garden shed year round for the last 5, and so far they’re fine. I wouldn’t expect a freeze thaw cycle to affect kiln shelves unless they’re getting wet.