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Hulk

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  1. Also trying new clays, IMCO reformulated "DC 3-5"*, an off-white stoneware, and "Terry Clay," a new light buff stoneware offering. Looking to fill the kiln for a bisque fire this week, then turn that around for a glaze fire. Other than that, I hope to host some local potters for a "Studio visit," throw lots of pots to pick from for next firing, explore outlets (wholesale and/or consignment) and make some progress on Studio upgrade/remodeling. Mainly, enjoy spending time in the Studio! I'm a lot closer to being pain free now, energy is much better (still lots of room for improvement there, however), and although more "cold" weather is certainly in the offing, the longer days help, and it's warmer these last few days. Mainly ii, I'm feeling more comfortable at the wheel lately, almost back! *Likely on account of finite supply of C-98 talc (looks like IMCO still has some C-98 available).
  2. Hi Lee, Welcome to the Forum! Good question, hope you get some first-person experience responses. ...meanwhile: Laguna shows four distributors in Mexico, one in Mexico City Laguna Clay | Distributors Is it sane to build a pottery studio in Mexico? - MexConnect “You can get high-fire clay and materials for your studio from Marie in Mexico City. She ships truck-loads of supplies from Laguna Clay in Los Angeles and distributes them to potters all over Mexico.” The potter, looks like they passed away last year. I haven't found Marie... Volume establishments, (e.g. Anfora) may give you some tips on suppliers. Amaco dealer Taller – Esmaltes, equipo y herramienta para cerámica (esmaltesparaceramica.com) Shops that appear to have raw material Bizcocho CDMX:) Servicios y Productos | Arcicor
  3. Liner glaze, translucent white. Clear blue, variegated green, red, variegated blue ...uhhm... teal blue. Six! There's scrap glaze, spills and wipe ups, wash offs, and such, it adds up after a while; when there were a couple gallons, I sieved and adjusted it. It's gray-blue, light gloss. The seven colors exhibit a range, depending on the clay, firing, and whatever may be fuming nearby in the kiln. I use seven underglaze colors, all Speedball. Some yellow would be nice, maybe via adding stain to the liner glaze. This year I want to get Faux Celedon (Selsor's) back in the mix... Down the line I expect to simplify. Each recipe is unique. I'll typically use three or four colors in a glaze load.
  4. Two hours, maybe? Fans can speed things up a lot. Turn the wares frequently and consistently. Do some trial runs? We had three hours - lecture and lab - in Wheel I (and Wheel II) at local Junior College ceramic lab, although we could stretch that a bit by showing early. To speed things along, we could place our just thrown ware on outside tables*, in the wash of a large fan. From there, turning the ware every ten minutes or so - important for keeping things round. That seemed to work better than placing wares in the warm box. In warm dry weather, from clay prep to trimmed ware in three hours, easy. In damp cool weather, more of a challenge! I'd tried draping plastic sheeting over wares to keep them until next class. Ugh, how I loathe plastic sheeting. Then I brought my own bats to class, and covered the wet wares, on the bat, with upside down buckets, which I still do. Some prefer to load a "damp box" with their wet wares. During open lab hours, some used electric "heat guns" (looks like hair dryer), which was somewhat frowned upon - several ruined/scorched bats, lots of whiny noise. I brought my map gas torch a few times; its heat is much more focused than the heat guns' outputs. One must be careful, however! *Outside, for the fans kick up dust.
  5. Clay is a major creative activity for me. The first thing that came to mind (yesterday) was problem solving. My last full time working gig (and the two full time working gigs afore the last, similar) was all about problem solving - software, configuration, communication protocols analysis, et cetera - I miss it, somewhat. Immersion in detail, research, analysis, application, testing, documentation - the time just flew by. ...and, every once in a while, someone appreciated the work. I'm posing that defining "the problem" and "problem space" - where we believe the problem exists - is a creative exercise, where imagination, flexibility, and plastic points of view can be as/more important than grinding through all the possibilities. Grinding is, however, required. Grind. Retirement is nice. Now my main "others" include home construction/maintenance/improvement projects at our and our son's houses, biking, swimming, reading, and volunteer gigs. ...not so much "creative" in the typical sense. What I'm going to take with me when (aaah, in a half hour or so...) I get up (from this recliner, heh) to face the current home improvement project, we're creating all the time. Our lives.
  6. A green silicon carbide or diamond dust full size wheel for your bench grinder or angle grinder might not be necessary, given you've a Dremel type tool. A collection of diamond Dremel bits is fairly reasonable at Harbor Freight (see also Princess Auto). I have a set, they're working well, however, I haven't challenged their durability much (yet). I don't know how much heat is ok for tungsten carbide*. Looked like none of the discount tungsten trimming tools (I'd found when looking, previously) are sharpened. Many are tungsten steel**, as JohnnyK points out. Added: with a Dremel type tool, low speed and coolant are options. Tungsten carbide likely can take some heat; the inserts we used in machine cutting tools got very hot - we did use spray misters though. *Grinding can push the edge to red hot very quickly **aka "tool steel" and "high speed steel" - which is fairly tough, and a file may or may not "touch," depending on how hardened
  7. There's almost always several ICAN hits whenever I start a general search on topics ceramic*. I'm continually intrigued by how much traffic this Forum seems to get, many many Guests (readers who haven't yet registered) always reading topics here. *Specific, err, not remembering just now!
  8. The scorched looking spot doesn't look so good. Have you found any fuses? If so, is it burned?
  9. See 10-SEP-2020 update, second recipe, "Min's low expansion III" Clay composition and crazing - Page 2 - Clay and Glaze Chemistry - Ceramic Arts Daily Community I mix and sieve it, setting specific gravity to about 1.42, then adjust the thixotropy as needed*. I like the glaze, having tried, adjusted, then abandoned several clear/clearish liner glazes before getting this one sorted. Playing around with new recipes in coming years, likely, for my bag of Gerstley Borate will one day be empty, also the bag of Texas talc, and smaller sack of Petalite. *I'm stirring clockwise at a repeatable speed. Once the whisk is removed, I expect to see the mass of glaze revolving together at the same speed, for about three or four turns before coming to a stop, all together, and "bouncing back" a little bit. Glaze that's not sufficiently "gel" will spin much longer, with several currents running at different speeds. See Tony Hansen's article and video clip Thixotropy and How to Gel a Ceramic Glaze (digitalfire.com)
  10. Temperature can be measured fairly accurately*. For our ceramics, it's time and temperature, which is typically called "heat work." I'm about to head out for the day, will check in again later. *precision typically costs. For our kilns, consistency is likely more important than accuracy.
  11. That glaze formula (ChristopherW, above) is within two percentage points of "Functional Clear" glaze (cone 5/6) that was available in a Studio setting where I started out. It went on well*, melted well - glossy, smooth, fit the clays, nice! ...however, I'm not seeing that it's particularly durable. The wares that have seen regular** use, the glaze failed, hence the wares were retired. I'm using a liner glaze that has much less boron, more silica and alumina, low coefficient of expansion... A nod to Forum regulars that provided feedback, observations, and formulation suggestions when I was looking to fit a liner glaze. I ended up abandoning a few (at least four) formulations and adjusted what I'm using now several times. *After thorough stirring, I'd ladle some out to a clean container, sieve it, check specific gravity, adjust the thixotropy, glaze my ware, then dump the glaze back into the communal bucket. **The wares that see occasional use and are otherwise "babied" by hand wash with mild soap and No Soaking are still looking good.
  12. Good questions. Good to be back at it too! I had some big gaps over the last fifteen months, ramping back up lately. Given your pyrometer gives consistent readings, you may be able to get very close to the desired heat work by correlating the temperature and time to the cones' bends. Your goal, very likely, is "heat work," not so much temperature. A kiln that heats up quickly (over the last hundred degrees or so) will either run up to a higher temperature, or hold at peak temperature, to bend the cone, where a kiln that heats up slowly at the end will bend the cone at a lower temp. Pyrometric Cone (digitalfire.com) Some atmosphere exchange is likely good, allowing fumes to escape and oxygen in. Likely one peep open - typically the top one - not all. The heat, especially once past low red (cone 6 is light orange to yellowish), is getting to your wares almost all by radiation, very little convection. Expect that there will be hotter and cooler areas in the kiln. This can be mitigated somewhat by: loading the hotter areas with more ware, shelving, and posts (iow, mass); loading the cooler areas with less ware - tall is good, for shelves are very heavy; manipulating the controls. My first kiln, fitted with a sitter, was controlled by three switches, each with off, low, medium, and high settings. First firing, way overfired. Subsequent firings, I watched cone packs set by the peep holes*, took notes (times, temps - via brand new pyrometer, switch changes, final results) and tweaked the setter until it was fairly close. After several firings, I was confident that reading the pyrometer was sufficient, however, I continued to place cone packs in each firing and note results. I bought the portable pyrometer Skutt sells (it's a TPI 343** ) I never did trust the setter to shut down when just the amount of heat work I wanted was achieved. The setter mechanism, to me, is a failsafe, which will shut the kiln down (either by the cone melting, or the timer expiring) in the case I fall asleep or somewhat***. That said, there are many potters that trust their sitter and get good, consistent results. See online tutorials for repairing, refurbishing, and adjusting your sitter. *kiln glasses are super important for protection against harmful rays and any superheated flying bits! !! ** 343 Dual Input K-Type Thermocouple Thermometer with Field Calibration | TPI USA (testproductsintl.com) ***I'm also watching the new kiln, which is fitted with three zone automated firing control, and taking notes.
  13. On the left, 600g (~1.3 lbs) mug. A normal/medium mug for me, 350g, however, as the large and extra-large ones, people pick them up, 600g is now "medium" size. The turquoise plastic tumbler is handy as a "rounder" - the taper fits most mugs, and the shape is, strangely ideal.
  14. Looks like the J230 was spec'd as GrayB indicated*. The voltage, aren't most homes supplied with 240v? Be sure that matches up. fwiw, our home is 240v (the kiln's display indicates ~252v). Our run is very near fifty feet. The (e23T-3) kiln's plate indicates 48 amps. I'd considered going with the number four wire, but went with the #6 The cable we bought is rated higher ...75 amps. The vendor, WireandCableYourWay, had a good price** on #6-3C THHN-PVC TRAY CABLE WITH GROUND We also went with a fuse/disconnect box and replaced the supplied cord and plug with a waterproof conduit and #6 wires. *Not sure about the new models, just got several hits for J230 and 43.98 Amps Ah, GrayB uploaded an image. **The per foot price hasn't changed. With shipping, still less expensive than local vendors and better specs. I went with three conductor cable, for down the line someone might need (or want) 120v ...the third conductor is not being used in our setup. My understanding is the kiln (our kiln, the e23T) requires two conductors only, and the ground.
  15. Hard to say without picturing it. Does it look like a lubrication point? Any luck identifying where the noises are coming from? Potential noisemakers: motor - bearings, brushes, both; wheel shaft bearings and/or bushings; belt, belt pullies; any of the moving parts rubbing on something.
  16. Thank you C. Banks! ...I'm looking at the article on sustainability now, also interested in the Coppage, Faber, Schade, Yimnirun, Davey, and Randall articles, oh, and the "Why Science Communication Matters" one as well.
  17. This topic resonates. Found this article (thanks to C. Banks for the link to the article list), "Actions for a sustainable future: Jürgen Rödel" here for transcript: Ceramic Tech Chat transcripts - The American Ceramic Society ...there's option to listen to the readings as well.
  18. Bein' curious, and settled down for a late afternoon snooze*, taking a minute to look for that... ...found a scanned version of Hopper's book. The piece is "Trifoot Plate - Southwest Series." Searching that string, found on Hopper's blog the same/similar image, captioned thus: "RH - TRIFOOT PLATE - SOUTHWEST SERIES. THIS EXAMPLE SHOWS CONTROLLED LOCALIZED FUMING OF CHROMIUM RED GLAZE ON TOP OF TIN-OPACIFIED TERRA SIGILLATA" Here: PHOENIX: BRUSHSTUFF #1 (rhrising.blogspot.com) Sorry about the all caps, that's a direct copy/past (quotes added, of quote!). *Had appointment this a.m. (6:30 !!) with the specialist for a root canal. Yep, time for a nap!
  19. Hi Vpwilkie, welcome to the Forum! The wheel is belt driven? ...where there are pulleys on the motor and wheel shafts, and a belt that connects them? If so, there would be bearings in the motor and also bearings for the wheel shaft. If the noise is definitely coming from the motor, it may be possible to replace the motor bearings...
  20. Good question. A few patterns stand out: Where the largest mug in the display sells. I've bumped up my mug sizes several times now; what is now "medium" used to be rather large, heh. Some, no, many folks cruising the wares will go straight to seconds (minor cosmetic defects) and/or marked-downs, looking for a bargain. Much less often, a looker will beeline to the best piece in the display, and grasp it, then buy it. More mugs and bowls go than vases, teapots, and jars. What's happening seems to make a difference. When there are people picking up ware and not putting them down (! a buyer!!), others seem to follow along. Same for interested, happy, engaged, interested (yah, twice), inquisitive people. Somewhat same in reverse though. What people see, lots of variation there. Some see the prices. Some see the shape, others the color, or decoration, others watch the other shoppers most closely! Some are really looking closely at the potter. I like to see interested shoppers picking up and handling wares that interest them, for I (like to think I) make pots to be used.
  21. Looks like the image Bill posted correlates "o'clock position" to degree angle. I'm not finding many graphics that depict correlation between degree angle and degree temperature. This one is a large cone 10 cone; the rate* is indicated (in °C) The temperature degrees per angle degree is greatest at the beginning of the fall/bend, least at the end. More fun here: Untitled (thermaltechnologies.com.au) How closely we have to hit the target for heat work for optimal results may certainly vary. In my (limited) experience, within a half cone to a full cone is plenty close enough for bisque, given that it's not a full cone on the cold side, for then I have to rush a bit to keep the glaze layer from being too thick. I don't mind having to slow down a bit for bisque that's not as absorbent... For glaze fire, some clays are much more sensitive to overfiring than others (per that same limited experience). *Temperature difference between clock/angle positions depends on the rate - how fast/slow the temperature is rising.
  22. Do the holes go all the way to the clay? ...looks like they do (also not scientific!). If so, perhaps there are some larger "off gassing" particles in the new clay? They appear (also not scientific) to be random - all over the surface. If you're dipping, the glaze layer near the foot should be thinner. Are the problem forms thicker than your test tiles? If so, that could be another indication of problem particles, for the thinner wares "burn out" more and faster in the bisque. And so, if the new clay has more/bigger bits of stuff to burn out, a longer more thorough bisque fire - with plenty of oxygen - could help. See also drop & hold glaze fire: Drop-and-Soak Firing (digitalfire.com)
  23. To drop and hold, the next segment has a lower target temp/target. Here the rate is maxed at 9999, and the hold is long, three hours (crystal formation), and the final segment is a controlled cool, falling two hundred degrees at the rate of 500°/hour, then holding there for a full hour. For a bisque hold (per prior post, to burn out stubborn organics in thick wares, and/or clays with lots of organic!), I don't believe it matters if the hold is on the way up or down. When running my manual kiln, I held at 1500°F on the way up and down! The new kiln, I set the 1500°F hold on the way down. See "Custom Ceramics Program" in the L&L notebook. Give a shout if any questions come up? There are regular members (and Mods) here that are very familiar with writing and editing custom programs. There are Horned Lizards in California! Grackle, the figures, how charming, and beautiful glazes, thanks for sharing!
  24. All my flexible metal ribs are stainless steel, except for three, which are carbon steel (else a high enough stainless to rust*). Steel may be "blued" - it's pretty (subject to opinion, of course) and helps protect against rust and scratches. Bluing (steel) - Wikipedia ...blueing can wear away fairly easily, and additional measures against corrosion/rust may be necessary. If you like the rib, rinsing it clean, then drying it off and giving it a wipe with an oily cloth may not be too onerous? If you do keep an oily rag about, hang it up or put it in a fireproof container, for spontaneous combustion is a real thing, Spontaneous combustion - Wikipedia Just rinsing and drying may be sufficient, try and see. *Low series stainless steel contains more nickel and chrome. Higher series stainless steels may rust. added: metal ribs can become very sharpened through use! Does anyone else square off the honed edges with a file (or grinder, sandpaper, whetstone, etc.)?
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