Hulk

Hi Ceramics.np.04, Above I'm disagreeing with PeterH, looks like your kiln is rated Cone 10 (or more), not Cone 6. I should have been more specific. A Cone 10 kiln element set should last a good long while when used to fire to cone 5/6. I'm just saying it looks like a Cone 10 (or more) rated kiln.

Looks like 1300 °C is well over Cone 10, excepting particularly (very) "fast" heating rates...

I'm seeing the range of tested absorption - very low (1% or less), low (2%), somewhat low (2-4%), not low (5%+)* - for high fire clays and mid fire clays. I'm still thinking absorption has to do with formulation/ingredients and firing to the specified cone. *these range labels reflect my opinions!

Looking at the cones, that's direct feedback. With the bung having to be in, then getting stuck, relating the pyrometer readings and clock times (for temperature rate of change) against the cones might be the best you can do. That's assuming you have a pyrometer - from there, take notes on the readings (time and temperature), then compare against the cones afterward. After a few trials, you will be able to repeat your heat work by watching the pyrometer and the clock! ...that's assuming that your pyrometer is consistent and reasonably accurate. Heat work Take a long look at a cone chart, noting the relationship between time and temperature. In short, it takes a higher temperature to slump the cone when the rate of change is faster; the cone will slump at a lower temperature when the rate of change is slower. "... Are we talking about welders glasses for IR & UV protection?" Yes, also protection against any flying bits! The odds that something would go ping and fly into one's eye are minimal, yes, but not worth chancing. For sure, don't look into the yellow hot kiln without protection! I'm seeing several welding supply shops in northern UK, where a decent pair of Fronius UV wraparound glasses are about fifteen pounds. Added: or, as Bill points out, these (IR and UV) Warrior Safety Spectacles Smoked (weldsafe.co.uk)

Hi Shaina, I've no direct experience with matte glazes. Looks like a matte finish glaze with a bit of greenish blue that doesn't move much. What Cone are you firing to? What type(s) of clay are you using?

Hi np.04, Is your firing governed by a controller? If you are able to set cones where they can be watched*, that might be a real help - you could start your cool down when the heat work is completed. *be sure to wear kiln glasses against the harmful rays and any flying bits!

Quieter than the vacuum cleaner method! Looks good.

...how's this? It's not the three-inch brick though. Circa 1980s Skutt 1027, the original brace is attached just forward of the point/angle that is in-between the flats where the handle and hinge (fore and aft) are attached. Let me know if there's another angle that would help, and/or anything else. Raising and lowering this lid, am being very careful, deliberate, and slow, for there is some flaking that I don't want to make worse. I'll be offline for most of the day, will check back asap...

Hi Gonen, Welcome to the Forum! Generally, contains manganese and iron, sometimes a stain (which likely has manganese in it)*, perhaps iron chromite (likely a rarity these days). Per my experience (one twenty-five pound bag), be prepared for a few cycles of testing. Stay well clear of any fumes whilst firing. Tony Hansen's article on manganese and clays: Manganese in Clay Bodies (digitalfire.com) A forum thread on black clays: Black Clay Advice - Clay and Glaze Chemistry - Ceramic Arts Daily Community More links: clayart - thread 'black clay safety inquiry' (potters.org) clayart - thread 'black clay' (potters.org) *credit Min, here: Scarva Professional Black Clay bodies - Clay and Glaze Chemistry - Ceramic Arts Daily Community

Good question Kevin. Starting out, I was convinced that a natural gas fired kiln would be the best choice for me. Down the road from there - there isn't a place to set one up at our house, the neighbors are too close, a large enough gas kiln that works well would be heavy and expensive... I went with a used Cone 10 rated electric kiln to fire Cone 5/6 ware. I like it well enough that I'm looking to replace the unit with a new one when we move upstate. Electric may be more portable as well. The space, setting, and infrastructure available will likely be factors, also what kind(s) of work you are interested in, and your budget.

Callie's observation/speculation on "flow state" is resonating!

Getting better at somewhat unliked can help, also streamlining/improving the process, and/or the state of the unliked thing can help. For example, I'd grown to tolerate glazing, now I look forward to it - my skill having improved some, and the results as well. Another example, keeping a clean and organized (well, relatively) space is easier than facing a mess!

Many folks in my age group also experience this: that their body "lets them know" when they've done anything outside their usual routine, e.g. a light pruning session in the yard with hand shears - next day, hand and forearm screaming, upper arm, shoulder and back moaning. This started for me well over ten years ago. Maintaining a wide variety of activity can really help! So, the variety of physical tasks associated with pottery is good! Moving clay, handling ware, wedging, throwing, getting up and down, walking about, all routine, it is good, and I had ramped up gradually enough to avoid debilitating pain, so far... I'm a part-time hobby potter. Doesn't seem like I've been doing it long enough where worn out parts are because of pottery activity. That said, the maladies I brought with when first sitting at the wheel require some adjustments - both thumbs are compromised, I've some nerve damage to a few right-hand fingertips, there's shoulder damage, vision limitations, knee and hip damage, etc. Big picture, I feel very fortunate to be able to do just about all I want to, pottery wise, where the main obstacles are skill and knowledge, not so much physical limitations. My elders say, "Just wait!" which my experience and observation supports; meanwhile, if not quite "Do not go gentle into that goodnight" then a hearty use it or lose it is what I'm trying for. Regular aerobic activity has been a big part of my strategy, mostly road biking, supplemented by lap swimming. It's really helped! Almost twenty years ago my physical condition had deteriorated to the point that the walking my job required was daunting, and I was very overweight. I am fortunate, which I'm trying to remember and be thankful for!

Asbestos insulated wiring, asbestos varnished wire cloth, asbestos paper - were all in use as late as 1988. Also, asbestos woven cloth, and several other permutations, something to watch for.

"Anybody have a cold wax they can recommend that works well plus doesn't smell much when burning off?" Good question! I'm about out of what Aardvark Clay sells under their own label; it's an emulsion, and it does work ok. There's definitely a smell, but very little smoke. "Aftosa Green" is available at the supply place I can more easily drive to; any reports on that product? Any reviews on what U.S. Pigment offers?

Hi Roberta, I trim foot rings in just about everything. Here's a bowl too big for me to dip, where I poured the glaze over, first the green, then later the blue. Any road, the corner where the side meets the bare clay of the foot ring is well defined here, which makes it easier to tape off. Here there's a top edge to the foot ring - the profile is trimmed in tight, so there's a groove - even easier to tape off! I've been trimming this way lately, as it's easier to get a sharp line, also the groove catches glaze, and the bare clay portion is easier to burnish. The bottom portion, within the foot ring, I'm using liner glaze, where a squirt, using a ketchup dispenser, then wiped even with a wet finger does it.

Likely not an option for most*. I use masking tape for the sharp line at the foot; it helps to make a line in/on the ware where the tape goes - I cut a sharp corner where the foot ends and the pot body begins and burnish it - easy to tape to. The tape doubles as something to hold onto when dipping the pot upside down in the glaze! Also helps to pull the tape off before the glaze layer is fully dry - no dust. For big and heavier items, I'm pouring over (upside down), still using the tape on the foot, but holding onto the pot, glazing about half at one time. *I ran lots of tape in a previous life of house, car, farm machinery, and furniture finishing. ...and I like having something to hold onto, given I somewhat detest tongs.

Adjusting thixotropy* has made a big difference for me. Info help please with glazing Bisque for an amateur - Clay and Glaze Chemistry - Ceramic Arts Daily Community determining target specific gravity for glazes - Clay and Glaze Chemistry - Ceramic Arts Daily Community Brushing on glaze - Studio Operations and Making Work - Ceramic Arts Daily Community The other factor that stands out is practice and repetition. I'm using wax emulsion for a sharp transition between liner and outside glazes, masking tape for a sharp line at the foot, also for two-tone where I'm looking for the boundary to follow carved line or some other feature - tape, glaze, wax, wait to dry, pull the tape, then second glaze. *where the slurry (glaze) behaves as a liquid when moving, but gels when it stops moving. Rheology (digitalfire.com)

Almost all my wares are functional for food service, where all food surfaces are liner glazed*. Colored glaze recipes are from reputable sources and follow established best practices; all are food safe. I discount some wares with minor cosmetic flaws, otherwise, flawed ware is drilled for use as planters, hammered, or used in our house. No crazing (excepting display pieces), no cracks, no crawling. It has to look and feel right, be thick enough to withstand use without being heavy, be easy and comfortable to handle, pleasant to drink from (for mugs, cups, glasses, soup bowls), clean easily, withstand hot water and microwaving, not absorb water, and be somehow interesting. The hammer or drill is waiting. Standards can evolve. I'm still looking at, handling, using and evaluating ware - my own, and others, and trying different things, for example, I've set foot ring diameters now, and make the foot rim a bit wider. Standard diameters take away what was a variable - so I can throw to that diameter, the profile can be truer and more consistent, it's easier to trim. A bit wider foot ring doesn't seem to chip as easily but takes longer to polish and is heavier. I'm also "set" in so many things, heh. Usage may be the best test, also measuring absorption, heat shock test, lemon juice, banging until it breaks, soak in hot alkali solution, etc. Still working on culling at the wheel through final placement, it's a process. I still aim for making twice as much greenware as will fit into a bisque load, then cull and recycle. Kiln space is precious! Ware I otherwise liked (a lot) earn a parking spot in a planter bed - there's not many. Some of the teapots that don't pour right are there. * Low expansion durable clear - enough Zircopax to make it hazy - that goes on well, melts well, doesn't move much, doesn't craze. It's working. No other colorant.

Hi AngelaAngela, My understanding is the Skutt 181 requires the fourth wire*. The wire run to your dryer outlet may include the neutral. If the wire is there, be sure to verify it is properly connected to the neutral bus (at the breaker panel). Be sure the circuit's breaker is sized appropriately, very important! Likely the existing breaker will need to be replaced with the correct size. Here's a wiring diagram: Note: the elements run on 120v - that's why the neutral leg is required. The diagram clearly depicts "Neutral Essential" and "4-Wire Power Cord" *credit Dick White "Skutt 181 is nominally a 240V kiln, but operates the top and bottom sections separately, each on one 120V leg, and each needs a neutral. Hence, the 4 prongs: 2 hots, a neutral, and a ground." Replacing a 3 prong cord with a 4 prong - Equipment Use and Repair - Ceramic Arts Daily Community

If the motor is rebuildable/repairable, local small electric motor repair. Looks like Bluebird is a contact for Soldner pottery wheels: For Technical Support, parts and /or Service Call 970 484-3243 or email: info(at)bluebird-mfg.com Be sure to include your serial number. Bluebird Manufacturing, Inc. P.O. Box 2307 Fort Collins, CO 80522-2307 Phone: 970-484-3243 FAX: 970-493-1408

Regarding lead: "They haven't found a threshold level below which there is no harm." "Current research hasn’t been able to determine a threshold for many of lead’s effects. That is, scientists haven’t yet found a concentration of lead below which no effect occurs." I'm curious, is firing done in the same shop? If so, where does the kiln vent, and what procedure/protocol for handling kiln furniture, and et cetera...

Electric at .5 £/kwh is about $0.61 (US dollars), wow. In Central California, off-peak Winter is just over $0.28/kwh (was 34¢ in Summer). HBP, do the graphs depict percent absorption (water) by weight (vertical) for each trial (horizontal)? If so, that's some good results! I went with petalite (to lower liner glaze COE), cheaper per unit lithium (and avoiding the reported Spodumene foaming). Am seeing some small grey specks, but I don't mind them.

Looks like Keith is still in business; there's a phone number here: Furnace Kiln Repairs | Keith Company Comparing readings might be helpful, given you have access to a portable pyrometer, else compare your new pyrometer reading to a cone pack? There's more separation at higher temperatures... The wire colors appear to be a good first step.

The color might matter. The Axner site* indicates they've had good luck firing some of the colors to Cone 6. Both Laguna and Axner otherwise indicate the Silky products are Cone 06. "Some Silky underglazes can be fired to cone 6 for similar results as shown below; we've had great results with SIL10, SIL44, SIL45, SIL47, SIL54, SIL55, SIL58, SIL60, SIL61, SIL67, SIL70, SIL71, SIL74, SIL76, SIL82, SIL84."' Flamingo is SIL22? Still, might try it with a clear glaze - test it with a clear glaze over the underglaze. *Laguna and Axner merged some time ago. If I recall, Axner bought the Laguna company.