|
Someone made a ceramics thread... loving FINALLY. I've been doing ceramics for a bazillion years but the studio at the branch campus closed for COVID and then they lost their instructor so it was shuttered for almost two years. Meanwhile, I had a VL Lite and a KS609 so I made myself a little studio at home. I made a bunch of poo poo but glaze firing in a KS609 is pointless because you'd only be able to put like two pieces in there at a time so I've been basically been sitting on a pile of bisque until now. First glaze firing in years and you know what I found out? The clay that I got a few hundred pounds of and have been working with over quarantine?  IT loving BLOATS AT CONE 6 It's not all bad though. The pieces that used it marbled with other clay turned out fine.    Also, Majima turned out okay though if you look close, you can see some small bloats.  Anyway, I ain't buying anymore of that clay. When it's out, it's out. I think I'll fire my remaining pieces at cone 5 and see if that makes that much of a difference.  Bonus: Metallic Green from Minnesota Clay on Sandia Red from New Mexico Clay. Lareine fucked around with this message at 05:40 on Mar 2, 2022 |
#
¿
Mar 2, 2022 05:23
|
|
|
|
| # ¿ May 14, 2024 21:02 |
|
|
cheese eats mouse posted:Oh hey I’ve seen your work in the earth nation discord! It's a small world, smaller when there aren't very many ceramic discords out there! Harry Potter on Ice posted:Dang I'm feeling the last one. How did you approach carving the pattern? Not layout that's easy enough I found someone making tools that make that texture and copied them and made a tool out of an old gift card. Probably not as nice as a metal tool but hey, it works and is free!  In regards to your pitfire question, I do aluminum foil saggar sometimes which gives roughly the same effect without needing a giant hole in the ground. I put ferric chloride on either a burnished piece or a piece with terra sigillata, wrap it in aluminum foil with a bunch of chemicals and combustibles, put it in a big flower pot, stick that in a raku kiln and take it up to 1100. Take it out when it's cool, unwrap it, rinse it off and then put wax on it to seal it and make it shiny. Pieces turn out loving gorgeous. Haven't done it for awhile but I've got some pics of some old pieces.  
|
|
#
¿
Mar 3, 2022 01:23
|
|
|
Been quite busy these past few weeks. More and more of my quarantine bisque backlog is getting fired though I'm mostly focusing on the ones made with Sandia Red instead of the bloaty clay. I've also been working on photographing my stuff and trying out my light box. It's alright but it's a bitch to put together and it's quite narrow. It's sometimes a challenge to get a picture without getting the sides in the shot.   I've brought out my collection of discontinued low fire 4 oz. glazes and started glazing the things I made with fiber clay a year back. I've got a crab and a cat crab made. I've got the crab all glazed though I'm waiting on a few more discontinued Duncan glazes to come in the mail before I can finish my cat crab. I'm planning on doing a firing on Monday so I'll have pics of that soon.
|
|
#
¿
Mar 13, 2022 06:59
|
|
|
Man, that was an eventful firing. I got everything set up before hand. Ware loaded into the kiln, kiln plugged in, lid propped, bar set, weight up. Basically all I needed to do is go out and push the plunger and turn it on low. I woke up at 5:45 so I can get it started at 6, turned up to medium at 9, lid closed and turned up to high at 12. It would run about 2 hours, be shut off early since I was trying to go for 06 with only 04 bars, have a couple hours to cool and then the kiln would be opened. I've got a schedule here. I go out at the scheduled time and push the button. Guess what happens. ABSOLUTELY NOTHING. No light, no sound, no zip, no zazz. It's loving dead. I wanted to cry. I go downstairs, get a screwdriver and a multimeter and try to diagnose the problem. I have to sit down on the cold pavement, it's around 37 degrees outside and I use my phone as a flashlight to poke around inside and find something loose. Nothing was loose, poo poo was tight as gently caress. Only problem I saw were spiders. Lots of webs and spider exoskeletons. I close it up and try it again. It works! I go to set up the weight and then it goes dead again. But then it gets better. And then it dies again. This happens a few times but I FINALLY get the weight up and have the kiln be on. I get everything running around 8. Against better judgment, I decide to proceed with the firing. I wrap my cold rear end up in an electric blanket, sit on the bed and stare out at the kiln through the glass door. I'm afraid a stiff breeze will make it stop working so I spend most of the time on my phone watching the light, making sure it doesn't go out. 3 hours. 11 comes around, I turn it up. Another 3 hours. I take about a 30 minute nap. 1 PM, turn it up again and close the lid. Everything is going fine. I've decided that I was going to fire until the claw holding the weight moved the slightest bit and then turn it off when it did. I set up my tripod and took a picture of the claw every 15 minutes. It takes around 2 hours like I expected. A minute after I turn the kiln off, I hear lots of cracking noises from inside. Can't do nothing but worry for the next couple hours before the lid handle gets cool enough to sneak a peek. By this time, it gets too dark to take a kiln opening picture. I take a look and the crab seems to be intact. I take the crab out when it's able to be touched and this is what we got.   Glazes used were Mayco Mystic Mauve, Duncan La Fiesta and Mayco Elements Jade Moss for the eyes. All discontinued. It didn't overfire at all. No drips. The only thing that ran was the glaze on the eyes which was expected given that Mayco emphasized the "movement" of the glaze. I would say the only "bad" thing is that the Mystic Mauve crazed a shitload and really, it's a low fire decorative piece, who really cares? Even though it fired well, I'm a bit unhappy with the glaze choice. I don't think La Fiesta goes that well with Mystic Mauve. At the center portion of the legs, I did one coat La Fiesta and two coats Mystic Mauve but it really kind of looks like I only did a thin coat of La Fiesta, the other glaze doesn't show up much at all. I also put a few Duncan White Hot Color Burst Crystals on the claws but I think that maybe I should've done a few crystals of Blue Surge as well. That was Monday. Today I called up Skutt and asked a few questions. One was a long burning question I had about the age of my kiln, given that I got this kiln second hand and didn't know the year of manufacture. It's from May of 2000. Second question was how to get to the Switch Box and clean the contacts. They gave instructions, I opened up the kiln once again, didn't see any obvious problems with the contacts but blew out the box with some canned air and ran a qtip along the grooves. Closed it back up again and now it works. 10 out of 10 times it worked where as before it was more like 3 or 4 out of 10. TL;DR I tried to fire the kiln but it didn't work initially but I got it working and now I have a crab. Fixed the problem with the kiln, now everything is hunky dory.
|
|
#
¿
Mar 16, 2022 04:11
|
|
|
Wopzilla posted:I don't know how many goons have the capabilities to make their own glazes, but I have this old rear end book (probably 70s?) of interesting recipes. It's missing a few pages but I can post more of them if anyone has interest. It covers a lot of different glaze and clay body recipes. We've got a chemical room at school and I dabble in them. I've even "formulated" a raku glaze before, formulated in quotes because really all I did was make up a batch of 50/50 clear and divide it into test batches where I would throw a random assortment of colorants in. Picked out the ones that turned out nice. Woo, we've got a glaze. I've gotten a little more sophisticated since then but I'm still self-taught and I don't know how to interpret a oxide formula. But yeah, I'll look at some recipes.
|
|
#
¿
Mar 22, 2022 03:17
|
|
|
Wopzilla posted:
I'll just grab some Uranium Oxide next time I go to the clay store. Shouldn't be too hard! And I was going to say, what the gently caress are some of these frits. The only frits I've seen are all Ferro. Got any midfire in that book?
|
|
#
¿
Mar 22, 2022 03:52
|
|
|
Wopzilla posted:The book is all over the place but here are some that contain some cone 4 if that's what you're looking for. The oxides can be subbed out or added in most recipes. Swap titanium dioxide for cobalt oxide to make white turn blue, etc.. I typically work in cone 4-6. It's kind of funny though how now nobody works in things at cone 1. You're either a low fire glaze person 06-04, mid fire 4-6 or a high fire 10. Maybe commercial glaze manufacturers set things up like that but you don't have demand for anything else either. The Bristol glazes look interesting and I even found an example on Ceramics Art Network but the stuff about calcining the zinc sounds like a real pain in the rear end. I think we might have calcined kaolin already but zinc? Maybe later. Some of the interesting cone 4 glazes contain barium which 1. I'm not sure we even have and 2. I won't work with. It's just another thing to worry about and it's not considered food safe anyway.
|
|
#
¿
Mar 22, 2022 08:16
|
|
|
Wopzilla posted:If the zinc you have access to is made "french process" then it is already done. I'd be hesitant of any glaze that is a matte in this book and any recipe that you get off the internet. Even when making experimental glazes, I'll make most tests throwaway pieces. Anything sold, we get tested for food safety When you do food safety testing, do you mean you do the lemon test or do you get that stuff sent to an actual lab?
|
|
#
¿
Mar 22, 2022 22:09
|
|
|
Thinking about it, I should PROBABLY test some of the glazes I have kicking around for realsies before they go into rotation. In general, I have a LOT to learn about glaze chemistry and I've been kind of slacking off.
|
|
#
¿
Mar 23, 2022 07:12
|
|
|
 gently caress YEAH! CAT CRAB!
|
|
#
¿
Mar 24, 2022 20:10
|
|
|
That is a nice blue. I'll put it on the try list. Meanwhile, I've been watching lectures on glaze chemistry. I've been focused on this one potential glaze for rotation. It's a nice transparent cone 5 copper green. Here it is on WH8, the standard stoneware clay from NM Clay.  Here it is on Sandia Red in the sun. If you look close here you can see there's a bit of a problem. Crazing. I need to run more tests but it hasn't crazed on the WH8 yet. Simple solution would be to not use it on Sandia Red but I really love what it did with it and that's one of the standard clays I use at home. So my main glaze project is now to fix the glaze so it doesn't craze. It uses some frit 3134 and I found an article from Tony Hansen about subbing out some of the 3134 for 3249. Using Insight, I tinkered with the recipe and I think I have good starting point. Problem is... we don't appear to have any 3249. I say appear because the glaze room is an absolute goddamned mess. It desperately needs to be reorganized and consolidated. Often times we'll have two half-full containers of the same chemical. Some things are just hanging out in crumbling paper bags. I found a container simply labeled ball clay with no specification so I don't know if I should throw it in the OM-4 bin or what. I found a mystery chemical that I THINK is a base glaze but it's labeled as a frit and I can't find exact information about it. I don't know how old it is and what is even in it so it might have to be tossed. It's just... a big mess and I only have 5 hours twice a week during class to work on it. I'm also working on getting that cat crab in a local art show and it's kind of obvious I'm the first one signing up because the online form isn't working and I can't pay the fee. A bunch of unfun bullshit that forces me to deal with people. I bet I'm not even going to get in.
|
|
#
¿
Mar 28, 2022 01:28
|
|
|
We've got a sneaking suspicion that the kiln at school is over firing and the thermocouple is getting pretty manky looking. I am assuming that once we change out the thermocouple, the problem will probably be solved, right?
|
|
#
¿
Apr 11, 2022 21:59
|
|
|
Those holes are pretty extreme for pinholing. It almost looks more like blistering to me. Are other people having the same problem?
|
|
#
¿
Apr 11, 2022 23:38
|
|
|
Spikes32 posted:Yep every time I've seen this glaze on other pieces it has similar issues, though my example was one of the worst. Applying it thinly MIGHT help though at this point, the glaze might just be jacked up. Best avoid it. Not all glazes can be winners though it begs the question why it was put into rotation in the first place if these problems are intrinsic to the glaze.
|
|
#
¿
Apr 12, 2022 06:13
|
|
|
You just mixed some cobalt carbonate with some flux for that blue, right? Also, some of those volcanic ash glazes look really interesting, especially that one where it's simply mixed with gerstley borate and some bentonite. Though cone 4 is a bit low for my purposes.
|
|
#
¿
Apr 14, 2022 20:22
|
|
|
KOTEX GOD OF BLOOD posted:This is really a pottery q, and a dumb one. So uh can I put glazed stuff in the dishwasher? Or: how should I make pottery that's dishwasher safe? Depends. Your typical stoneware will be fine to put in the dishwasher. As long as the clay has vitrified, it won't really absorb water. Low-fire earthenware remains porous though so for that to be dishwasher safe, the glaze needs to cover the whole thing including the bottom, which requires stilting. You are most likely making things fired at cone 6 so you should be safe.
|
|
#
¿
Apr 21, 2022 17:39
|
|
|
When all the kinks are ironed out, how many plates you think you can put out? Is the limit the amount of dies you have made? Will you have to wait 30 minutes each time for it to release from the die?
|
|
#
¿
May 6, 2022 19:28
|
|
|
My cat crab got in a juried art show! Granted, it's just a small local one but still! poo poo, maybe the drat thing will actually sell. If it does, I guess I know what I'm going to be doing from now on.
|
|
#
¿
May 15, 2022 03:53
|
|
|
First week back at the school studio. I really haven't been able to work due to the fact my home studio is outside and it being monsoon season. I'm also not able to work inside either on sculpture and whatnot due to new kittens. Anyway, the studio is almost out of clear glaze and I have to come up with a suitable recipe before everybody starts painting all their poo poo with underglaze and wants a nice top coat. I've had issues with both clarity and crazing with a lot of the recipes I've come up with but I think I might've finally found a winner. I took a low expansion recipe that had lots of talc in it to the point of becoming almost semi-matte and cut some of the talc down and replaced it with whiting. I've been a few months off so I can't remember WHY I chose whiting but whatever. Maybe wollastonite would be better.
|
|
#
¿
Aug 27, 2022 08:22
|
|
|
We don't have a whole lot of Frit 3195 but we've got a shitload of 3134. If I change the 3195 for 3134 in that second recipe, I would end up with Tony Hansen's 20 X 5 with a soda feldspar instead of a potash one. I was going to use that as a base for touchy chrome-tin Mason stains. I'll keep those in mind though if my next test fails. This is the glaze I'm trying. Nepheline Syenite 30 Silica 25 Frit 3134 20 EPK 13 Talc 8 Wollastonite 4 There are a few criteria. Cheap, clear and underglaze friendly. And of course, not crazed. I would be able to reduce COE even more if I reduced the neph sye and upped the silica but I want melt fluidity to stay up so it can clear the bubbles that the body or underglaze might give off. It's also got enough silica as it is according to Insight. The test tile from the previous version turned out pretty drat good with no crazing or haziness on the white body tile and very very light crazing on the red test tile. Ideally, I want there to be no crazing on either but people use the white body much more than the red so that's our priority.
|
|
#
¿
Aug 30, 2022 13:12
|
|
|
Welp, the clear is a bust. Mostly because it looks like someone busted all over bowls.   I may tinker with the recipe at the future date since I love how it doesn't craze at all but I'm going to have to look for recipes again in the short term since we are on a time limit. It could also be an application problem since it's okay where it's thin but if the glaze is going to be fussy, it's not going to be much use since amateurs are going to be using it. I'm also going to have to scrounge for bisque to use as test pieces.  Ferro green is even more sexy than usual.
|
|
#
¿
Sep 3, 2022 22:22
|
|
|
Kaiser Schnitzel posted:I would like to start mixing big buckets of glaze at home because it seems faster and cheaper than brushing on commercial glazes. I've seen premade dry glazes at sheffield pottery and various other websites-is that pretty much 'just add water and mix' or is there more to it than that? I asked the instructor last night and she says they fire everything to cone 5 if anyone has favorite prefab glazes for that temp. Yes, essentially but you're also going to need a sieve. They often come with instructions on how much water to add. Just follow the instructions on the bag or on the website and you're pretty much good to go. Also, be sure to wear a mask or respirator. Mixing dry glaze gives off a lot of dust you don't want to be breathing. As for recommendations, you can't really go wrong with Laguna. The only problem I ever had with Laguna was when I accidentally let the bamboo matte dry out and I couldn't seem to reconstitute it without smashing it into a powder with a rolling pin.
|
|
#
¿
Sep 9, 2022 00:33
|
|
|
I guess I forgot to update you guys. I decided on a clear. I took some garbage plates of various clay bodies and divided them into 7ths and tried 7 recipes at once. Did a bit of underglaze and then painted in each section with a different clear. The winner is the one at 6 o'clock. It is a revision of Kitten's Clear. Just to be safe, I took the plates home and subjected them to the ice water test to try to force crazing. Kitten's Clear stayed the same. It's clear, it has no clouding, it works well with the few underglazes I used, it seems to be quite forgiving in application and it didn't appear to run on the one vertical surface I tried. The only problem I can see so far is the fact that the Gerstley Borate in it acts like Gerstley Borate so it's pretty thick. We'll see if that's a problem. I would like to do more testing but we are out of time. People needed to put clear on their underglazes today and most used Kitten's. So uh, everyone is kind of my guinea pig now. I'm a bit worried but there's nothing I can do now. UPDATE I saw the stuff that came out of the kiln and I am reasonably pleased. Only problem is that the glaze was clearly too thick for dipping. It's got around 18 percent Gerstley Borate in it so I'm guessing that has a lot to do with it. Don't know if I should just keep adding water or if I need to invest in a deflocculant like Darvan 7. All the brushed things turned out pretty good though. Lareine fucked around with this message at 20:21 on Oct 1, 2022 |
|
#
¿
Sep 29, 2022 03:57
|
|
|
Wopzilla posted:With it being a solid cast piece the bottom has some vacancies where air was trapped in the mold. They also stabbed holes along the bottom to act as vents during firing. Unfortunately there is a crack that formed from one. Vent holes? So it doesn't explode during firing from still being damp? I've seen that being done with people making cone packs but on an actual piece? Why don't they just let it dry properly before firing? Why don't they just candle it?
|
|
#
¿
Oct 2, 2022 11:17
|
|
|
Wopzilla posted:It's to prevent bloating during the firing. If we were able to see the cross section there are most likely large cavities where the slip didn't fill from casting. At a certain point during firing you have glass formation but the piece is still letting off gas (this is why you fire in a well vented area), and thus cannot pass through creating a blister OH THEY ARE FIRED ONLY ONCE okay yeah that makes sense. Sometimes I forget that mass-made ceramics studios do everything different from studio potters. Which is kind of dumb of me considering I went on a tour at the Heath factory in Sausalito.
|
|
#
¿
Oct 4, 2022 07:35
|
|
|
Wopzilla posted:An expected outcome to the press would be the scrap and how to reuse it. There was an option to send it back to the clay supplier but we opted to buy ourselves a little pug mill. Surprisingly easy setup and use. Bought a little push cart and attached it, just need to get a plastic folding table. It only puts out 25lbs per batch, but once I'm through this summer's mountain of scrap, it won't be such a daunting task to process it each week. It will also reduce our clay waste to near 0% Sweet. It would be great if we could get one of those for the studio. How you liking it?
|
|
#
¿
Oct 19, 2022 06:28
|
|
|
I'm surprised the firing only takes 12 hours. Maybe because it was a smaller kiln? I dunno, I always hear about wood firings taking literal days.
|
|
#
¿
May 8, 2023 18:41
|
|
|
I have been so goddamned busy. I joined the pottery club in January. By May, I'm on both the Steering Committee and the kiln crew. I also have glaze responsibilities. Of course, I happened to join at the time that one of the blue glazes started to spit. I don't know if the glaze is funny or people are applying it wrong or both. In either case, the result is still the same: me having to chip off globs of glaze from the kiln shelves. We must have safety glasses around here somewhere but I can't seem to find them. I've resorted to just doing it with my eyes closed. You get annoyed with people REAL fast when you need to fire their poo poo. Like, we've got a rejection shelf but it takes so long for people to remedy their mistakes that it's already full with other stuff and then I find poo poo like someone putting NO margin on the bottom of their pots at all and just putting it on a cookie. You can't give me ONE GODDAMNED MILLIMETER OF MARGIN? gently caress you, I'm wiping it. I'm wiping your poo poo up. Don't like it? Well, I'm sure you wouldn't like it when your piece gets stuck to the drat cookie and you have to smash off the foot. In less aggravating news, I sold this bastard. 
|
|
#
¿
Jun 1, 2023 08:06
|
|
|
Yeah, I noticed my clay store isn't carrying Gerstley anymore. Laguna STILL hasn't said poo poo about what's going on. Are they just running out? They said we had like 50 years worth.
|
|
#
¿
Jul 1, 2023 18:33
|
|
|
Wopzilla posted:The mine closed years ago and laguna has been selling from a stockpile. My supplier didn't get a heads up about availability, he said they knew something was going on when they were getting calls from suppliers across the country. The one pallet he had disappeared quickly. It's dumb to price gouge for materials that have cheaper replacements. It's not a 1 to 1 ratio and GB does have unique properties in how it gels but it can and will be replaced by 3134 if they try to price gouge. Granted, I guess they had issues involving production at the Ferro plants during COVID so 3134 isn't especially cheap at the moment but it IS a manufactured material.
|
|
#
¿
Jul 3, 2023 18:37
|
|
|
Kaiser Schnitzel posted:I can’t remember where I read it, but I definitely remember reading somewhat that GB causes a lot of problems with glaze recipes but because it’s what people are used to it still gets called for a in a ton of recipes. Reformulating those recipes with a frit could get the same effects without the problems? Yeah, it would take some tinkering but you can totally do it if you use a program. Some people actually insist on doing that anyway even before the shortage since GB has high LoI and makes your glaze into pudding.
|
|
#
¿
Jul 4, 2023 02:49
|
|
|
|
| # ¿ May 14, 2024 21:02 |
|
|
I haven't posted in awhile. I've been very busy with being a clay club steering committee board member. I'm also in charge of glazes and glaze maintenance and I load and unload the kiln because I clearly don't have enough to do and I hate myself. I'm even thinking about learning how to use the pugmill so I can have yet another thing to do for no money. I'm also working on a project to improve a legacy glaze that has been around the studio for years. It's called Riki White and it's an extremely simple recipe. 40 Gerstley Borate, 40 Neph Sye, 10 ball clay, 10 tin oxide. It has a great effect on red clay bodies and works well with texture but there are two main problems. One is that it's loving 40 percent Gerstley Borate. It's essentially pudding. Even at a proper SG, it's stupid thick. The other problem is that it runs like a bitch, possibly due to the thickness but possibly due to the large amount of Neph Sye. I've been thinking up tweaks, I just tried taking 5 from the Gerstley Borate and the Neph Sye and adding 10 percent silica. And it worked, it was less thick and it didn't run at all. Only problem is that it lost a lot of the things that made it special. It's whiter now instead of being an off-white and it still gets toasty but not as much as it did before. I'm going to try taking the 10 completely from the GB next and leave the Neph Sye at 40. Edit: I doublechecked the recipe and it turns out I was completely misremembering. It's loving 50 percent GB, 25 percent Neph Sye, 25 percent ball clay and 10 tin oxide. I did a revision on a loving revision that I didn't even know I made because half GB is ridiculous. Lareine fucked around with this message at 20:11 on Nov 28, 2023 |
|
#
¿
Nov 28, 2023 19:58
|
|