Oxide washes on top of glazes! Oh my!

[Callie Beller Diesel]

I’m a bit behind on my forum reading, so I’m only getting to this now.

This example is the exact reason why I don’t offer glaze choices outside my existing glaze stable to commission clients. But at this point for you, that’s a future consideration, and you have made a promise and you need to deliver. So. Onwards. 

As much as we all hate being told we need to test things, in ceramics you can’t get away from it. You’re probably not getting this saucer out of the kiln in anything less than 3 firings, but what goes into those kiln loads in what order is what’s up for debate. My suggestion is to do the tests before taking on the piece itself, but you’ll have to decide if the ADHD squirrel will let you do that or not. If you charge ahead without testing, you’re going to wind up doing as many as 6 to try and fix the screw ups. 

You need a darker-than-the-version-you-used glaze. Have you first tested to see if a thicker application of this glaze does what you’re describing, or is it an opaque one that doesn’t change much? Is it really flat, or is there some reactivity to it?

There’s actually nothing saying you can’t add stain to an existing commercial glaze to alter the colour, although you’ll have to do some testing to figure out if a stain or an oxide will work better to modify it.  You may void any claims about it being food durable, but that isn’t a concern in this instance. You’d want to make some line blends to find the right tint you want, but this could solve the problem. As long as the specific gravity of your glaze remains constant, you can add dry ingredients to x number of grams of the wet glaze,  sieve thoroughly (2x through an 80 mesh test sieve), and get repeatable results.

I think the best way to do a wash that gets wiped off of the high points on a texture would be to either try it underneath, especially if the glaze is in any way translucent.

If it’s opaque, you’ll to bisque, apply glaze, bisque again, apply and wipe the wash, and then fire a third time like I think you have been wanting to avoid. Sorry!

There’s nothing wrong with firing a kiln partially full, even if it’s more efficient to have other things in it.  It’s not stupid if it works, and you’d be surprised at how much firing an electric kiln doesn’t cost. Here’s a link to an archived thread describing how to calculate yours.

That said, filling the blank spaces with test tiles is a most excellent plan. You will pretty much never be sad to have  glaze tests as references, whether you think they worked at the time or not. The information you gain from them will help build your skill and knowledge base, which is incredibly important for anyone working with commissions or doing bespoke work. You need to be able to guide your clients through what’s possible and what isn’t, and you can’t do that effectively if you don’t know yourself. When I was working at the glass place I spoke about in the QOTW thread, we would make random stuff just to see if it worked or not, and they then got used as showroom samples. If there was space available in the kiln, we always put something weird in, or tried to ‘break’ something to see how hard we could push a material.

 

 

 

[ATauer]

18 hours ago, Callie Beller Diesel said:

I’m a bit behind on my forum reading, so I’m only getting to this now.

This example is the exact reason why I don’t offer glaze choices outside my existing glaze stable to commission clients. But at this point for you, that’s a future consideration, and you have made a promise and you need to deliver. So. Onwards. 

As much as we all hate being told we need to test things, in ceramics you can’t get away from it. You’re probably not getting this saucer out of the kiln in anything less than 3 firings, but what goes into those kiln loads in what order is what’s up for debate. My suggestion is to do the tests before taking on the piece itself, but you’ll have to decide if the ADHD squirrel will let you do that or not. If you charge ahead without testing, you’re going to wind up doing as many as 6 to try and fix the screw ups. 

You need a darker-than-the-version-you-used glaze. Have you first tested to see if a thicker application of this glaze does what you’re describing, or is it an opaque one that doesn’t change much? Is it really flat, or is there some reactivity to it?

There’s actually nothing saying you can’t add stain to an existing commercial glaze to alter the colour, although you’ll have to do some testing to figure out if a stain or an oxide will work better to modify it.  You may void any claims about it being food durable, but that isn’t a concern in this instance. You’d want to make some line blends to find the right tint you want, but this could solve the problem. As long as the specific gravity of your glaze remains constant, you can add dry ingredients to x number of grams of the wet glaze,  sieve thoroughly (2x through an 80 mesh test sieve), and get repeatable results.

I think the best way to do a wash that gets wiped off of the high points on a texture would be to either try it underneath, especially if the glaze is in any way translucent.

If it’s opaque, you’ll to bisque, apply glaze, bisque again, apply and wipe the wash, and then fire a third time like I think you have been wanting to avoid. Sorry!

There’s nothing wrong with firing a kiln partially full, even if it’s more efficient to have other things in it.  It’s not stupid if it works, and you’d be surprised at how much firing an electric kiln doesn’t cost. Here’s a link to an archived thread describing how to calculate yours.

That said, filling the blank spaces with test tiles is a most excellent plan. You will pretty much never be sad to have  glaze tests as references, whether you think they worked at the time or not. The information you gain from them will help build your skill and knowledge base, which is incredibly important for anyone working with commissions or doing bespoke work. You need to be able to guide your clients through what’s possible and what isn’t, and you can’t do that effectively if you don’t know yourself. When I was working at the glass place I spoke about in the QOTW thread, we would make random stuff just to see if it worked or not, and they then got used as showroom samples. If there was space available in the kiln, we always put something weird in, or tried to ‘break’ something to see how hard we could push a material.

 

 

 

You may have missed the parts where I have said that the glaze is extremely opaque, that I even put on two washes under the glaze on the actual moon jar and not a damn thing showed through at all. I also slapped my forehead because I wasn’t thinking at all when I said I could fill the kiln up with test tiles, since I fire at cone 6 I really don’t have any cone 06 glazes that needed to be tested and while I will have likely some of the earthenware clay left over not enough to make a ton of test tiles, and I don’t want to waste my dwindling supply of good raku clay I love on test tiles for glazes I won’t use. I figure I will probably make a few mugs (the exception to my absolutely no mugs rule is for myself, and most of our hodgepodge of commercial mugs have broken so I could use a few more for using for me tea- ones that won’t be allowed to be used for the cat’s water, since all 4 cats refuse to drink out of bowls or even fountains they will only drink out of cups and mugs, because they think they are drinking out of what we are drinking out of, weirdos). 

I know that each individual kiln firing is not a huge huge amount of electricity, but I am trying to save on that as much as I can, the kiln I’ll be using is absolutely huge unfortunately. As for the glaze, no more layers does not make it darker. I really don’t see how I would end up with doing it 6 times if I don’t test it, I am doing something I have done a hundred times, brushing on stain with some frit to emphasize the texture and wiping off the high points, I could do it in my sleep, and while very close up you’ll be able to see it from farther away it will just look darker. I’m only doing the other two saucers not because I’m worried about the stain but because of anything else that could go wrong that would make me happy to have a couple extras- a crack, a chip, etc. 

As a sculptor I have an extremely large number of glazes I work with, I don’t have a large enough studio to have very many in buckets as there just isn’t space for that, so only a chosen few get to be in buckets. Most of the others I have already made up are kept in quart sized yogurt containers or gallon sized old kitty litter containers. These are for my medium to small scale work and tile and wall panels, with quart and pint containers housing my many different colored slips (which I use a lot, I love love love slip), homemade underglazes, and colored terra sig. For the majority of my work which is large scale- as 5-6 ft or even more, I mix up the glazes I want to use on the sculpture in the amount I need, and save any left over in the smaller containers. Because I can very easily do things with glazes, and don’t have a set palette like a lot of people because that would just not work with how I work, I have no problems making up new or different glazes for commissions or custom work. Remember as a sculptor who only rarely makes utilitarian work, commissions and custom work for me are usually quite different than requests from a customer to make a mug in a certain color or something. I assume that for a lot of commissions and public art that I will have to even develop new glazes in order to make work that is satisfactory. I have no problem with that, especially since contracts are my best friend, where I get to lay out that I will do my best to achieve certain colors if those are requested, but due to the nature of glaze making that I may not be able to achieve the exact color requested, but will try to get as close as is possible. 

Really, I think a lot of advice for custom work for potters doesn’t translate over to sculptors very well. Our commissioned and custom work is very different, often architectural or public art, where contracts spell things out very well and protect the artist from pretty much all of the situations that seem to bug potters. For fun and relaxation I do make a tiny amount of functional work, just because I like the forms, or for vases I can make them very sculptural, and I can also for some things use glazes that I would rarely get to use on sculptures but really like, like floating blue for example. But each piece is a one off and not repeated, except for the occasional sets of stemless wineglasses I make, but each set is unique and will never be sold with that glaze combo again. Because it is important to me that any of those things are unique, I won’t take custom requests on those. This situation is unique for me because I would only do this for this specific friend, just like I am willing to make a set of custom mugs for him but would never do that for anyone else…unless they are handing me a suitcase with a million dollars in it. I do the functional work because it is fun and often creates canvases that I can go crazy with surface decoration, lots of slips and underglazes and seemingly clashing designs but as one of my mentors says I’m like a jazz musician who can take the disparate melodies and make them work together to create something that she says is a Tour de Force piece. Or having the chance to do intricate Sgraffito, that and carving are quite literally my favorite things to do in sculpting, but when I’m making 6 ft tall sculptures I have a lot less opportunity to do Sgraffito and while I can do some carving not usually very intricate carving with a lot of piercing and so forth…the pieces are just too big and it would take too long to do those things, although I do try and do some of it, but they tend to me long lines that cover large spaces instead of what you can do with Sgraffito on a cup, a plate, a platter etc. 

But back to my original point, I love glazes and have so many different colors I want to use, more than I get the chance to, plus add in my wide palette of colored slips, terra sigs, and underglazes- since I make them myself with mason stains using Vince Pitelka’s recipe(s) from Glazy, I have way more options than those using commercial underglazes, and for 1/5 the price, if I was a functional potter I would be very unlikely to have an actual “glaze stable” as for fun I am always trying new glazes, using SiC on reduction glazes, doing line blends and triaxial and quadraxial blends to adjust a glaze or try and find a new one, so I would likely jump at the chance to do some custom work with a different color/glaze, if it is a color I like- I’d probably say no to yellows or oranges. But I would have a short contract spelling out the possible limitations and what the client’s backup choice is for a glaze, and depending on how much work I would have to do charge accordingly for the time spent on the glaze. 

But I look at someone like Joe Thompson, who has invented a crazy number of glazes in the last few years, and always very generously shares them on Glazy and his blog for everyone to use, he loves the process of developing new glazes and has a real knack for it, and he then gets to offer more of his limited amount of functional pieces he offers in these colors, so I could see someone like that enjoying the challenge of trying to develop a new glaze for a client who wants something specific knowing that if I would succeed in making the glaze, or close enough to it, I would increase my money making opportunities, but again have boundaries with the client that they are paying extra for the glaze research time and testing and that if I am not successful they either need to have a backup glaze they are happy with or a quit fee for the project if they would rather not have anything at all. Part-time for a few years towards the end of my scientific career I did some scientific/medical writing, and I learned a lot about contracts and how important it is to build very detailed requirements on the clients part and what they want very clearly spelled out, with all my limitations spelled out if some things can’t be delivered on, but being paid appropriately for the amount of work especially if there is more work than is typical for a project, charging a project fee, having that fee paid in three installments, 1/3 up front, 1/3 at a certain point of deliverables, and 1/3 on final delivery of the product. And to have a kill fee in it if the client wants to terminate the project that I get paid for however much work I’ve already put into it including calculating in that while I was working on that I could have been working on something that would have gone to completion and paid me more since that would have been finished and I would have gotten the entire payment. Ceramic artists need to be embracing this model and get paid partly upfront, especially if it requires you to get any materials you don’t normally have on hand, at some kind of middle point, and then on final delivery of the product. And if custom work requires extra effort on your part of any kind, whether that is using a glaze you don’t usually use so you have to do some test tiles, a test bowl, and then possibly the BWIC, microwave, cutlery etc tests if you need to determine its durability and whether it can be used on food surfaces, then that should be factored into the price. I can’t think of any other industry or artistic practice where it isn’t already assumed on the part of the client that asking for custom work means you are going to be paying more. I have an addiction to gorgeous Indigenous made earrings I developed during the Pandemic as a weird way of coping with the Pandemic stress, and if I ask for something custom, colors or something, I assume I will be paying more. Sometimes I don’t, especially if I ask to buy a set of earrings that has already been bought and the artist offers to make a custom set similar in design to those earrings but lets me pick colors or length or width more, they may sometimes just charge what that original set of earrings cost, but I never assume that will be the case. If you want to talk to me at the next NCECA look for the white woman with either black or turquoise hair who is wearing every day beautiful, often very long, Native earrings…

[ATauer]

On 7/2/2022 at 8:51 PM, Babs said:

Right so a visible saucer does need the attention you are giving it.

Your glaze is very opaque and does not move?

Your glazed pot could be sintered, then stain aplied and wiped. If glazr is very opaque, underglazing won't work, you'll ned an onglaze technique.

Could try adding low temp frit to the onglaze stain to add to its flow and melt and thus it will pool

Sintering it is a really great idea, I think I will try that out. I’ve mentioned a few times that I make my mason stains 1:2 with FF 3124 and water, I don’t ever use mason stains with just water, so it should be plenty sticky and have a bit of flow and even gloss, since 3124 at temps like 06 is in fact a complete glaze within itself. I try and avoid using Gillespie borate (don’t have access to Gerstley locally anymore) with the stains if I can because I find it gels up the mixture more than I usually want for what I’m doing, but it is also an option especially for people who are having trouble getting frits right now.

I really like this idea- I’ll have the two others glazed in case for some reason this doesn’t work. I need to start thinking of some creative ideas of what to do with the hopefully superfluous extras I’m making, if I have one or two left over that are perfectly good I feel like I would need to make some planters for myself that would fit these saucers, or, since the rest of my work in made in paperclay, and you can add wet paperclay to glazed clay, even if it isn’t paperclay, I could use these or carefully broken parts of them added to a paperclay sculpture, wallhanging…something. I really really hate wasting clay and while I marvel at the really cool chemistry that is vitrification (or I guess actually sintering at lowfire temps) I wish there was some way to have your clay turn ceramic permanently but also have something you could dip it in or spray it on that reverses the process and the clay could be recycled and used for something useful. But probably the simplest thing if I ::knock on wood:: have extras would be to make some planters for myself that match, I’m positive my mom would have plenty of plants that could go in them. 

Thank you so much for the sintering idea! I don’t know why I don’t think of sintering things more often, there are a lot of good reasons to do so!

[Babs]

14 hours ago, ATauer said:

Sintering it is a really great idea, I think I will try that out. I’ve mentioned a few times that I make my mason stains 1:2 with FF 3124 and water, I don’t ever use mason stains with just water, so it should be plenty sticky and have a bit of flow and even gloss, since 3124 at temps like 06 is in fact a complete glaze within itself. I try and avoid using Gillespie borate (don’t have access to Gerstley locally anymore) with the stains if I can because I find it gels up the mixture more than I usually want for what I’m doing, but it is also an option especially for people who are having trouble getting frits right now.

I really like this idea- I’ll have the two others glazed in case for some reason this doesn’t work. I need to start thinking of some creative ideas of what to do with the hopefully superfluous extras I’m making, if I have one or two left over that are perfectly good I feel like I would need to make some planters for myself that would fit these saucers, or, since the rest of my work in made in paperclay, and you can add wet paperclay to glazed clay, even if it isn’t paperclay, I could use these or carefully broken parts of them added to a paperclay sculpture, wallhanging…something. I really really hate wasting clay and while I marvel at the really cool chemistry that is vitrification (or I guess actually sintering at lowfire temps) I wish there was some way to have your clay turn ceramic permanently but also have something you could dip it in or spray it on that reverses the process and the clay could be recycled and used for something useful. But probably the simplest thing if I ::knock on wood:: have extras would be to make some planters for myself that match, I’m positive my mom would have plenty of plants that could go in them. 

Thank you so much for the sintering idea! I don’t know why I don’t think of sintering things more often, there are a lot of good reasons to do so!

Another thought is you run a dry straggly brush loaded with wax lightly across the top of your saucer, thus screening the high bits from the wash  when you then apply the underglaze, or stain to your piece. The high points, well most,  would be coated with wax resist, the wash would be taken up by the low bits only???

Maybe,  i e like dry on dry watercolour technique, or masking with a stiff sparse brush...

[ATauer]

3 hours ago, Babs said:

Another thought is you run a dry straggly brush loaded with wax lightly across the top of your saucer, thus screening the high bits from the wash  when you then apply the underglaze, or stain to your piece. The high points, well most,  would be coated with wax resist, the wash would be taken up by the low bits only???

Maybe,  i e like dry on dry watercolour technique, or masking with a stiff sparse brush...

I will keep this in mind for the other two saucers if the sintering doesn’t work. Brushes are my weakness for tools, I am constantly buying new ones and new sets, even though I’ve barely used the set I just got before! And with me starting a specific body of work very different than the rest of my work, where I want to do majolica on cone 6 black stoneware (leaving parts of the clay uncovered or carved so that it is obvious I am not using terra cotta) I’ve become obsessed with buying lots of calligraphy brushes, having found out they are really the best for doing that kind if painting, and that they hold a lot of paint/glaze so you don’t run out when making a long line…so I don’t have much in the way of old stiff scraggly brushes- probably one or two old wide wall paint brushes in the basement, otherwise I had gotten rid of any brushes I couldn’t recondition so I could buy more, good quality brushes for pretty much every possibility…except this apparently! I do have quite a few of the extremely inexpensive chip brushes from the hardware store in different sizes that I had bought for applying silicone to models for molds (since I am also a glass caster and usually make a master mold, and sometimes I make master molds for models for my plaster molds, but I tend to just have around 5 or so plaster casting molds going at any one time, for strata casting, so each casting has unique layers and colors of porcelain and the carvings revealing those colors are always unique, and to keep things fresh when I get bored with a casting type I just throw the mold away and make some new ones, with the idea that these are all limited edition unique castings, so a master mold in that situation is usually a waste of time and expensive silicone!).  

The chip brushes are pretty stiff and with some extra bending and beating up by me might work. I could potentially try it out on a smaller piece, bigger than a test tile but not one of the actual saucers, with the same texture, to see how that works. My sense is that there would probably be a good amount of the high points that wouldn’t get wax on them and would be black, and that the wax would also seep into the valleys preventing the black from getting in there. This had actually been one of my first ideas for a way to try and avoid 3 firings, but I just didn’t think it would work. I had also considered doing sort of the opposite, using one of my thin liner brushes and carefully putting wax on each ridge, but that would be so incredibly time consuming I rejected it. When it comes to painting or Sgraffito I can really get into a lot of detail work, but I think this is one of those things where it would just be too much!

[Min]

When you are out of hospital and are able to posting a photo of the Moon Jar would be nice to see to put these comments into perspective. 

[Babs]

I use a fan brush for majoica, dry on dry almost, bt hve to play. Waxresist can be quite thick,  not runny like v hot wax..

[phook]

This is facinating. Can't wait to try it. Do I fire the oxide to the same cone as the previous firing, or keep it lower to prevent the previous glaze from running?