Hyn Patty

Any of you have any tips or tricks to share for reconstituting dried out porcelain slip? It's still a little bit buttery so it's not rock hard. Figured I'd add some distilled water, ball mill it a bit to smoothly remix it, then see if I need to add any sodium slicate but hopefully it'll be just fine. This is the last of my batch I picked up more than ... eh, 25 years ago? I've had it a while. But shouldn't really be any different than reclaiming clay scraps I should think.

My last gallon of Seeley's porcelain slip dried out! Drat. I've had this stuff for the past twenty+ years but not used it in years. When I went to add distilled water it turns out the plastic container was cracked. No wonder it dried out on me! So, chipping it out so I can get it into my Shimpo ball mill jar to remix it until it's buttery smooth again. No pouring porcelain medallions in the studio today. Thankfully, even though Seeley's went out of business long ago, I can still get it from New York Dynamic Porcelain. They bought the rights to Seeley's product line and still make Seeley's porcelain slips and china paints. Thank goodness because this is my favorite porcelain slip and I'm going to need to put in a new order soon.

You are all very sweet, thank you. Nice to have a community where we try to help each other out, share info, and encourage one other. Many I time I've asked for help around here and gotten great input. So I'm glad if I can give a little something back.

Been a while since I posted about this piece. I have been really busy with so many other things. BUT I did get a rubber master cast made of my medallion. I made it using platinum silicone I managed to get on super sale at a much lower price per gallon than usual. Which is good because I needed a few gallons for my projects though the shore hardness wasn't quite as high as I usually use and that has caused me some issues with the Porthos mold reproduction. Anyway, it's not being an issue with the small medallions I am reproducing. Here is the Cob medallion's rubber master and the first production plaster poured. Once I've cleaned it up and it's cured, the plaster is ready to use if I want to pour open mold porcelain pieces or I can make a mold back with pour hold for a little thicker pieces, or pieces with backgrounds if I want to go back and carve into the plaster while it's still soft. So many possibilities! Anyway, this is the time for me to go back in and redetail anything I want to touch up in my plaster while it's still soft and hasn't fully cured and hardened up fully yet. But one of the things I am going to do is clean my rubber masters very well, then box them up again and pour ANOTHER layer of platinum silicone over top, to produce a negative. Once that sets up I'll have a food safe rubber mold I can use for ... *drum roll please* ... casting CHOCOLATES! OK, maybe I'm just a little bit of a nut. But why restrict my mold making for only ceramics? What fun to do your own designs, your own molds for ceramics, /and/ get to eat your cake too! So, I can hardly wait to see this boy cast in white and dark chocolate just for fun! I'll be giving away some of the porcelain medallions at up coming shows as awards this summer but why not /also/ give away some chocolate medallions for awards too?! Hahahaha! Maybe I get a little carried away.

To wrap up my little saga on this first ceramic Porthos - he successfully sold at auction yesterday for more than $1600 and I am quite pleased. Yay! Alas, I am having issues with his mold so there will be no more of this edition forthcoming until I resolve those issues or make an entirely new set of plaster mold pieces. I master molded the original plaster mold pieces using silicone but I ended up using a shore hardness 1 step softer (30A instead of 40) and I'm having problems with the new plasters being warped and NOT fitting back together correctly. Even though the silicone rubber pieces are each in their own mold boxes around the sides (but not the bottoms). Grr. I should have known better! Moral of that story is do NOT be lured by being able to get two gallons of platinum silicone for half the usual price on sale when they are not the correct shore hardness I need. Close, but no cigar. Ah well, maybe I can fix the issue by making simple plaster jacket molds for the bottoms of silicone molds so they can't possibly warp from the weight/pressures of the wet plaster filling them. I think there is a very slight gap there that's sagging so it may end up being an easy fix. Maybe. I'll just have to try it today and see. Meanwhile I have already printed a replacement Porthos of the same size and version to make a new mold from. I made the first mold set to cast him in pieces for testing my bone china slip I'm making from scratch here in studio but I also want to be able to cast him as close to whole as possible for earthenware production anyway, so back to the drawing board with claying up... I'm also working on molding him in a larger version so I may well have the big boy casting before I have this smaller version back into production. One never knows! Murphy's Law always rules whether I like it or not.

Might benefit from a small addition of gum arabic. It's rather fragile and the binder might be helpful.

All right. For an initial test I have mixed up about 1/3 cup white earthenware slip (cone 06-04 that I got locally and ball milled it a few days) and to this I added about a tablespoon of vinegar. Mixed it up and it bubbled a little bit (a lot of the recipes mention vinegar but not sure why exactly). By morning it had settled on top as a clear fluid and the slip had become rather unplastic, sort of more like wet sand than slip. I poured off the excess fluid. Then I added about 1/2 a teaspoon soda ash and mixed it in well. It tried to form a hard crust so I had to put it into one of my mortars and use the pestle to grind it smooth again. I have a rather large ball mill but alas, not a little one. Maybe I should make myself a smaller porcelain jar and little balls for just such things ... but I digress! The last thing I added was 1 ml of sodium silicate, mixed well then a touch more. It became very creamy and lost the hint of grittiness. I have no idea how it will preform but now I'm going to test it. Not sure if the vinegar was actually any help at all or not but the soda ash and sodium silicate made sense. I'll let you know how well it works or doesn't. I'm going to test it filling in tiny defects and a crack in a bone china horse sculpture I want to glaze. My initial reaction is it has a good feel, much like the bisque mender I had been using and loved. I can always color adjust afterwards with a little airbrushed opaque white underglaze if needed over it to blend it in before I move onto coloring the piece. Wish me luck! I'll be firing it to cone 04.

And thank you for your kind words. I've been doing equine sculpture and sculpture finish work since 1976, and ceramics since 1984 though I didn't have kilns of my own until 2003. I posted (but forgot that I'm not supposed to) the links but if you didn't already get them, just message me. I want to abide by the rules!

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 did see Kyanite mentioned in a recipe along with sodium silicate on Digital Fire here: https://digitalfire.com/picture/3164 Looks like a cone 6 patch. I mostly do low fire fixes but I do have this one noted for higher fire projects.

Thank you, I appreciate that feedback, Min! You always have great tips and advice to share. I did order some soda ash (just one lb to test) as it's handy for a number of things, but I will keep the baking soda conversion using heat in mind. Very nice, thank you!

Anyone here swap sodium bicarbonate for sodium carbonate? Different PH but baking soda I have seen mentioned to be used in place of soda ash. I might try that for a recipe test making bisque mender as well.

I've also found this one on the Lakeside Pottery website. Anyone tried using this one and loved it? It is also based on using your clay and adding soda ash and sodium silicate. It's for making 1 gallon at a time so I'd need to cut that down a lot for smaller units. I don't have soda ash on hand to try it but I may get some. https://www.lakesidepottery.com/HTML Text/Tips/pottery-magic-mud-magic-water-paper-clay.htm

The one I'm testing now I found on Instagram and is this one and can be fired to whatever the base clay requires that you use: This recipe is for repairing cracked bisque before a glaze firing. add: 1 cup your clay slurry Add: about 1/4 cup shredded toilet paper Add: 1 1/2 TB vinegar. Any vinegar will do. Blend with an emulsion blender stick. Don’t skip this step. It should be the consistency of coarse toothpaste. You can add more paper to make it harder or more vinegar to make it pastier. Pack it into the crack. When it has dried dry sand it smooth. Glaze as usual.

I've been using a commercially made bisque mender for years that I just love. But it's no longer available of course - Coloramics. Sadly I do not know the ingredients to try to duplicate their formula. I've tested several other bisque menders trying to find a good replacement that doesn't cost an arm and a leg. I just don't like any of them. Amaco Bisque Fix comes well recommended but it's pricy even before adding in shipping and is a far larger jar than I am likely to ever use up. Most of the other commercially made replacement bisque menders I have been testing shrink WAY MORE than the Coloramics product I had been using. For example: Mayco's Clay Mender is horrible. Shrinks badly and fires to a pink color. So, who has good bisque mender recipes to share? I've found some that use paper clay mixtures, some that use my own clay but adds vinegar or soda ash, or a little glaze (or all three). Low fire to cone 04 will do but up to cone 6 is also nice. Any suggestions you care to share here? Obviously making and testing my own versions is underway right now in my studio and I can make whatever I need practically for free instead of paying $30 for some product plus shipping. Ideally the lower shrinkage the better and I need it to be strong and fire white. I've always been wary of paper clays and concerned about how strong they are after firing since it opens up more voids and is more porous than the original. Also paper clay is a real PITA to get into tiny hair fine cracks. Opening up cracks in bisque ideal but is only feasible under certain circumstances and not in others. Please share your thoughts and recipes. I'm sure I'm not the only one who will benefit from input. Thank you! Once I settle on one that works really well I will be glad to share it here for others to try.