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Callie Beller Diesel

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Everything posted by Callie Beller Diesel

  1. I think the first step would be to identify what you want the storage and inventory system to be able to do, and what about your current setup is working and not working. Also, we need to know what you have to work with. Do you have a dedicated space that is art-only just needs reorganizing or are things scattered in different areas and is next to your Christmas decorations? Is it convenient to access and do you need it to be? What kind of things are you storing and why? Someone storing sculptural pieces long term for eventual collectors or galleries is going to have different requirements than a potter storing work between shows. Answering that before you even start taking inventory is important, because I’m going to suggest setting aside a day to set up a photo station and documenting things as you take inventory, and what else you need to record will be informed by that.
  2. Laguna 50, and any other clay body with manganese speckles tends to experience bloating if you go much hotter. It’s not the clay itself, it’s the manganese granules breaking down and creating gasses that form pockets in the clay, or may contribute to pinholes and blisters in glazes. If you want to understand what happens to clay inside the kiln, start with this digitalfire article. Any terms highlighted in blue are outbound links to definitions or other articles that will explain things in more depth. There’s also more links and definitions stuff at the very bottom of the page. Cannot recommend this one enough to beginners.
  3. Can you let us know which one, and the glaze as well? Most suppliers put their information online, and google translate is pretty good in the event the specifications aren’t already in English. More information would help us give the most practical answers.
  4. If the piece is collapsing that drastically, it’s not the size of the grog or the amount of it you’re using, it’s how much the clay that the temper is in is melting. You said this does not happen with earthenware, which is usually not fired to the point where it begins to melt as much. You did not mention if you used a porcelain or a stoneware to make this piece, or what the product specifications of it are. If the clay is not meant to be fired to the same top temperature that your glaze is, you will have to change the clay to something that is. Or fire it with a support of some kind, much like you have it propped on in the first picture. The movement in the work in progress image has a lot of movement: using the kiln to create some more could be an interesting idea.
  5. First of all, don’t feel bad for not knowing what the different components do. There can be a lot of moving parts that determine what each thing does in relation to the others. Chemistry is about proportions, and changing proportions will change the results. Lateral thinking in this instance is not a detriment, because whether or not a result is “good” or “bad” depends on context. Some people want a crawling beads glaze for special effects, but on the inside of a serving bowl it’s a defect. The easiest way to go about this with your level of chemistry understanding is to start with a glaze of any colour that has the sheen level and bucket qualities that you already have experience with. This will eliminate a lot of testing variables and points that need refining. If you don’t have a suitable candidate, the base that Roberta provided is a good starting place. You would then take any colouring oxides out of it, leaving you with what we’d call a base glaze. Colouring oxides are metals like iron, manganese, cobalt, copper, chrome, etc. Anything with a very noticeable colour to it. Rutile is also in this category, because it’s a combination of iron and titanium, with trace quantities of other stuff. Then you want to replace those colourants with one or more opacifier. Which ones and how much depends on how opaque the glaze needs to be, and whether or not you want the clay to peek through on the high points or not. In pottery glazes, there’s 3 things that can be used as opacifiers: Tin oxide, Zirconium compounds (usually zircopax in North America), and titanium dioxide. Tin needs to be used in larger quantities (8-10%) to be effective, which can be an issue due to the price. But it gives a softer, very aesthetically pleasing white on it’s own compared to the other 2. Zircopax is less expensive and gives a very stark, bright white with not a lot of visual variance. It can also stiffen a glaze, which may or may not be desirable. Titanium is technically a variegator, which means in smaller quantities (1-3%) it’ll give glazes that floating blue effect, which is called phase separation. But if you use more of it, (7-10%) it’ll give you an opaque yellow, or even orange colour. Using it by itself won’t get you a proper white glaze, but it can add subtle visual interest. To fine tune your white glaze, start with a line blend of your base glaze with one opacifier each. You want to find out what the ideal amount of each opacifier is to get the coverage you want without having the end result use more materials than you need. This doesn’t need to be too extensive: 3, 5, 7 and 10% increments will give you enough info for this. If you find your ideal glaze in this round of testing, you can carry on with making your work. Be sure to use small cups as test tiles to get a better idea of what each glaze will do when actually in use. If the sample size is too small, they’ll all look the same. Once you’ve determined your sweet spot for each opacifier separately but nothing’s really calling your name yet, do a triaxial blend with the 3 opacifiers. For a really nice description on the least painful way of doing this, I recommend Derek Au’s article here.
  6. If you’re getting clay in the dryer, the items aren’t coming clean enough in the wash. I would venture the culprit isn’t so much the soap you’re using as the amount of soap, and possibly the amount of water. If you use too much deterg, it can build up in the cloths/towels, especially if you have a high efficiency machine. If you do have an HE, make sure you’re using an HE detergent, and don’t use the provided cap to measure it. The caps are too large, and encourage over-use of product. Get a shot glass or a 1/4 cup measuring scoop. Excess detergent builds up and traps clay dust, as does any use of fabric softeners, dryer sheets or those scent bead things. If you’re using any of those, stop. They’re unnecessary for studio towels. If static is a concern, the wool dryer balls are great! Especially if you have a more water efficient washer, you may have to pre rinse items in a bucket to get the largest bits off first, and use the heaviest duty cycle available. You may want to try giving it an extra rinse, or even running the cycle twice if you’re still having dusty leftovers. If you’re using a front loading washer, this may not be the best thing for this job. They’re great for protecting clothes, but they weren’t designed with clay studio level of dirt in mind. If you have been using fabric softener or dryer sheets, you might want to do a laundry strip to remove the buildup. Try not to have to do this often, because it is hard on fabric. Not as hard as bleach, but it’s still not an every week kind of thing, Fill a bathtub with the hottest water you can, or use a top loading washer using a hot water cycle. Dissolve in 1/2 cup borax, 1/2 cup washing soda and 1/2 the usual measure of your existing laundry detergent. Add the cloths and soak for 4-8 hours. Use the longer time if you have hard water, less if you have soft. After this, the water will be shockingly gross! If you’re using a bathtub, drain the water and give everything a passing rinse. Run through your regular washer without adding any additional detergent. If you’re using a top loader, just close the lid and let the heaviest duty cycle run.
  7. I think it depends on the clay body. If you’re working with a really fine toothed clay that’s prone to readsorbtion, I could see excess slip possibly creating some structural weaknesses. Scale might play into this too. If the potter was Adam Field and he was talking about his larger Onggi jars, rim cohesion is going to be a bigger structural integrity consideration on those pieces than on a mug. Personally I use chamois to smooth out the rim, but I also shape everything with a metal rib. That doesn’t leave a lot of excess slip behind, so redistributing whatever remains is just hiding whatever coarse particles lurk. I think an entire weekend workshop could be taught on feet and rims. What I use for a rim tends to be very piece specific, and what the pot is supposed to do. For bowls used in the kitchen, i like a rounded or otherwise beefed up rim that is chip resistant. For mugs, I make a round rim that I then create about a 30* angle on the inside that helps cut off liquid flow. Still chip resistant, but a nicer feel for the user. It also makes for a clean liner/outer glaze demarcation. Jars with lids have their own functional considerations as well. Those tend to be more vertical, because I don’t want the gallery warping inwards and trapping the lid in the firing. (I have to get into the studio, but I’ll try and get some pictures to upload later.)
  8. It might help to describe exactly which part of the business you’d want the part to take care of. Do you want someone who’s going to execute your designs or take care of what I’d call the clean (as in not covered in clay) side of things?
  9. Spooze and magic water are similar enough to each other, but I don’t know if either is the right tool for this job. Re: deflocculated slip, most white clay bodies can be deflocculated, and the results will create an incredibly strong join. I agree that making a patch slip with some paper fibre in it to fill non-structural cracks would be a better option in this case. Mixing some up is pretty straightforward if you’ve ever done paper making with a blender. To make the pulp, use the really cheap toilet paper, 1 ply if you can get it. This is no place for the quilted stuff the cartoon bears like. Tear it into squares and soak it down in enough hot water to make it go through the blender easily. Process it until it’s well disintegrated, with no distinct pieces. Drain well and gently press out the excess water in a sieve, but don’t compress it. Make some slurry out of your clay body: if you have dried pieces you can slake down, this is ideal. If not, slice some existing clay into really thin pieces and slake in hot water for an hour or so, and a stick blender should be able to handle making about a cup of slip that’s a thick pudding consistency. Add no more than 30% by volume of the paper pulp to the slip and mix well with the stick blender. You can eyeball this: it doesn’t need to be exact. It’s just one of those “some is good but more is not better” sort of guidelines. You can either use the slip as is to fill small cracks, or dry it out into a more typical working consistency to fill larger ones. The paper fibre will help fresh clay bond to both dry clay and bisque. The join may be somewhat visible due to the smear marks from blending the clay: this isn’t super avoidable. If you feel really strongly about it, sanding some of the texture down after the piece is bisqued can help. You will have to re-fire any patches on bisque before glazing.
  10. @Rae Reich do you figure it’s the compression or the deflocculant in the casting slip that makes the cast items less sound for carving? How do they go wrong if they’re going to, in your experience?
  11. I think most phones or tablets have some of this functionality built in already as assorted disability supports. Things like Siri and VoiceControl on Apple products (and the Android equivalents), are a great example of disability supports that able folks can benefit from. But they don’t always have intuitive setups. Most of us already have our preferred music, podcasts, audiobooks we can download from the library or subscription services, YouTube, movie and tv streaming services. Switching between them with voice commands is already possible, but maybe not intuitive. So there may be something that can be done in terms of making an app that will switch between media types, or integrate some existing features more smoothly.
  12. If you engage with pottery at home, I'd love to know: - how did you start? [e.g did you take a class, see it online etc] - what are you using [e.g store bought materials, pottery kits] - what are the challenges you face doing pottery at home? - do you think integrating a digital element, such as an app, with your practise could improve the pottery experience? how do you see a digital element aiding you while you practise pottery at home? I’m going to qualify this by saying pottery is my job, not a hobby. I do pottery at home, but that’s because a home studio has much lower overhead than renting a space. 1) I started in high school art class, which was about 30 years ago now. I went on to get a BFA in ceramics. 2) Not sure what you mean by this one. They don’t really do kits for individual pottery projects, like you sometimes see with knitting or small woodworking projects. While a box of clay and some simple hand building tools can be had for under $100, the larger pieces of equipment like kilns can be pretty expensive and require special wiring and enough space to set up. The closest thing to a pottery kit would be a workshop with materials included. To answer the question as written, I buy boxes of clay 10 at a time, glaze materials in 50 lb bags, and I’ve owned most of my tools for a decade or more. 3) this is my profession, so my concerns are different than those of a hobbyist. But I’m at the point where I can crank work to my hearts’ content, but I miss a bit of the social aspect of working with a group. 4) as mentioned by others, apps tend to be pretty impractical with dirty hands. My pottery experience of throwing a lot of repetitive and kinda boring work is not the same as that of a hobbyist or beginner: enhanced feels like the wrong word entirely. I use podcasts, audiobooks and music to help me stay focused. But it’s worth noting that not everyone likes or wants background noise when they work.
  13. Food colouring works great. I use powdered graphite diluted in water to brush guide marks for berry bowl holes, and that burns off in the bisque quite nicely. I use red clay and need something darker than food colouring. It can be a bit dusty if you use too much though.
  14. Suggested fixes in order of least likely to cause problems to most: 1. discard the clay (not ideal, as there’s 5 bags you suspect) 2) do a project that doesn’t involve firing the clay, or use it for glaze cookies/wasters/cone packs/waste clay for mould making. (again, a lot of clay to do this with, but you don’t have to do it with all.) 3) Slurry mix and sieve your reclaim to remove suspected plaster lumps (lots of work, time consuming, but 0 risk of changing clay chemistry, involves owning a suitable sieve) 4) slurry mix your reclaim until there are NO lumps anywhere in it (time consuming, lots of work, low risk of changing clay chemistry, involves having a heavy duty drill and attachment) If there’s plaster lumps you either want to remove them entirely, or basically dilute trace plaster with the rest of the clay. Given the amount of clay you mentioned and that reclaim slip is usually pretty thick, using a stick blender will burn the motor out. If you want to try blending the slurry you’d have to use a drill with enough torque (usually the corded kind) and a grout or mortar mixing attachment to get every single lump out. Or sieve it. It doesn’t have to be an 80 mesh glaze sieve, a fine enough kitchen strainer will work. If you think you've got dry pieces with hidden plaster bits, you’re better off discarding them and making new. I do not recommend attempting to get around this with slow bisque at all. Especially if you are in any kind of group setting and you don’t own the kiln.
  15. No it doesn’t, and that’s really foolish of them, IMO.
  16. Getting a white glaze is easy. Getting a nice white glaze involves a bunch of fine tuning. I appologize! Where did I loose you, and I’m happy to backtrack. There are no stupid questions.
  17. That definitely looks like bloating to me too. If your clay is rated to higher than 1220*C, I’d contact your supplier. That’s not supposed to happen on an underfired clay body, and you may have a bad batch.
  18. If your plaster is still as soft as you describe after several weeks of curing, that’s a good indication it’s past its best before date. Or the plaster was measured by the “peaks” method instead of weighing the water. Plaster becomes a problem in a fired object if there’s a large enough piece inside the wall of the item. If conditions are right, the plaster can absorb water from the environment (think of porous earthenware possibly absorbing water in the washing) and swell inside the piece. Then you get something called lime pops, and a piece will chip off the side of the pot. You are correct that if the plaster bits are too small to create enough force to break the piece, you’ll likely never notice them. If it’s evenly dispersed in the clay body, it’s essentially a little extra calcium. Sieving with an 80 mesh isn’t a bad idea, as long as you aren’t removing any desired grog or temper. If you slurry mix your reclaim and you can’t see any lumps, it’s similarly unlikely to cause any issues. If you don’t want to reclaim 5 bags worth, you could use it for something like cob planters or other unfired projects. Plaster contamination bits that haven’t dried fully may release steam in the bisque, possibly causing the dreaded explosion. It’s not a lot different than if the rest of the piece was too wet and the early stages of the firing were too fast.
  19. We are asking if the wire is Nichrome or Kanthal, which is the material it’s made of, not so much the size of the wire. If the wire is Nichrome, it’ll have a lower heat tolerance than the Kanthal will. To be fair, there’s no mention of its composition or firing limits in most online product listings when I do a google search, and the sales language is VERY misleading. Kemper refers to high temperature in relation to a lot of their products that are meant for low fire. So “high temperature” also includes mid-fire by their definition. If you go to the Kemper website, there is a product labelled High Temperature Wire, and they do say that it will tolerate up to cone 5. At cone ten, I would not be surprised to see distortion.
  20. I’m a big fan of Ravenscrag slip in recipes, but I can get it easily. It should be able to be special ordered in the US from anywhere you can get Alberta slip from. They’re from the same supplier. It gives a good white gloss over the red clay I use, but you want a satin. Currently I’m doing some testing on Sue’s Calcium Matte from Glazy, and trying to take it into satin territory. It’s got really great colour response, but I’m finding it crazes a bit, and the iron tests discoloured with vinegar overnight. I’ve got a line blend with silica going into the kiln next week that I hope will address those 2 problems. I can share results in about a week and a half from this writing. When creating a white over red clay, if you have a glaze that already has the flow and application characteristics you like, mix a batch without the usual colourants and add 7-10% total opacifier instead. I prefer to mix opacifiers, because it tends to make for a more interesting glaze. I like titanium and zircopax, or tin and zircopax, usually just a 50/50 split. If you do this, use at least a small cup for a test tile. Using the usual 2” extruded guys won’t give you enough of an idea of the subtleties that will show on your main body of work. In choosing a base glaze, think about whether or not you want to completely obscure your red clay with the white glaze, or if you want some texture to show through. If you want some texture, a well melted or slightly fluid glaze will be better. If you want a more majolica look, look for something stiffer.
  21. All of my teachers in college were pretty focused on form, so we were forever and always looking at feet and rims as important design points in every piece. They’re small details that can either make or break a good pot. The chapters on feet and rims in “A Potter’s Workbook” by Clary Illian are the main reasons I recommend it to anyone starting out making pots. These are the 3 profiles I’ve been using the last few years. If a piece is more or less cylindrical, I favour a rolled foot that creates a little shadow underneath the pot, so it doesn’t look like it’s glued to the table. Teacups get a trimmed and altered foot, because they’re supposed to be a little bit fancy. I used to do most of my bowls with the unaltered version of the teacup foot rim, but lately I’ve been playing with creating an upside down S curve on my bowl feet. I also will leave at least a little exposed clay on most of my pieces, because I think the clay itself is really lovely, and I like contrasting it with the glaze. Feet tend to be a logical place to do that.
  22. Bisque makes great slump and hump moulds for handbuilding on, but I think plaster is a better tool for slipcasting.
  23. There isn’t a difference in the tax amount on a $40 item with a $20 shipping fee and a $60 shipping included item going to the same place, the way RevCan calculates it. The $20 (closer to $25 in real life) in the equation is the pre-tax cost of shipping and ought to include a little padding for shipping materials and shipping cost variation. Since you’re adding this charge to whatever your mug retails for, there should already be some money incorporated into that base price that’s expected to go towards anything you have to do to sell the piece. If you’re not paying for booth fees, travel expenses and wrapping to use at a market, that money gets put towards your web hosting and helps offset the odd overage in shipping.
  24. Usually if a commercial glaze turns out more brown than you want it to, you need a thicker application. Because you mention this being for someone else, as a heads up, Laguna 50 has an absorption rate that’s higher than ideal for functional ware. If you wish to proceed, any glaze that crazes on this clay body will likely lead to weeping.
  25. I have been summoned! What Min said: what do you want in a white, and what clay are you using it on? Give me an idea of what look you’re trying to create.
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