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You can get small digital pyrometers, hand held devices, not very expensive in the scheme of things. I would install a timer set at about 1/2 hr post target cone drop. This is a backup, essentialimo, inxase the sitter bar doesn't drop for some reason. Long time potters, eg @Pres can guage the temp according to colour if kiln interior but until colour shows you're in the dark. :-))

I would like the clay to be somewhat smooth - not necessarily like porcelain but not super coarse.

I am not too concerned with the color of the clay/Aardvark is near me. As far as the cone of the clay, I am hoping to stay in the cone 5 range but these pieces are sculptural and will only be for display purposes.

I'm not familiar with Laguna bodies. Is that the only brand you have available near you? Is vitrification and glaze fit important to you, or do you prefer a cone 10 body so it's more forgiving? I assume you want white, not brown, since you were using BMix?

do you have any good recommendations ? im firing in the cone 5-6 range

Could go faster to 1500F then resume your regular schedule. edit: I just read your other post about this in the another section, given they are very important pieces the safest bet would be to do the same schedule but without any candling (if you did this). Maybe go a bit faster but not breakneck speed. I'm going to delete your duplicate post.

Do you recommend starting the bisque over and taking the whole 7ish hours? Or do you think it’d be fine if I were to do a quick ride up to the 1500 and slow it down from there?

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This thread is a continuation of this one started by @Mark C. regarding the addition of another K2O feldspar to replace Custer: Vardhman feldspar from India. Chart comparing Vardhman with other potassium feldspars plus the analysis I received from Vardhman.

I have the analysis for Vardhman, I'll add a pinned thread on potash feldspar changes. edit: Pin link added here. https://community.ceramicartsdaily.org/topic/41698-potash-feldspar-comparisons-of-custer-mahavir-g200eu-and-vardhman/

Good find Peter. When I look at the analysis for both there are other differences too though. Definitely a fragile mechanism to get the green. Reitz Green with Gillespie doesn't need the lithium carb and dolomite additions when I played around with altering the recipe, the silica is a tiny bit higher in the Gillespie version but given the differences in the Floating Blue recipe that might or might not be consequential, I don't know. A simple addition of iron with a reduction of cobalt would be simple to test Hansen's theory if it translates to Reitz Green also. I suppose RIO would be the logical material to add as long as speckles don't become an issue. Or black iron oxide might be better if you have it.

I would. 1550F is approx cone 012 so pots are going to soak up glaze much faster than a typical 06-04 bisque.

@oldlady emailed me photos but was unable to post them here. These are her photos and show where she has reglazed some areas.

No, Min suggested switching to a commercial glaze used in an Amaco underglaze colour chart.

the glaze used was made by the instructor, did i miss where it is actually a commercial glaze?

Any relevance? https://digitalfire.com/material/gerstley+borate ... at the bottom of the page, discussing substituting Gillespie Borate for Gerstley Borate ... Clearly, the Floating Blue itself is firing greener than usual. And the Gillespie Borate version is much bluer. You may be used to something in between these two. The green tones could likely be restored by a reduction in the cobalt and increase in the iron oxide.

Yes, that's the Reitz Green we have used; with 2 rutile.

I refire things, usually for very similar reasons described. Rarely do I add more glaze. Either they work or they don’t, but they do often enough I keep doing it. If there’s a piece I’m on the fence about I will hit it with 1000-1500 grit wet sandpaper first. It’s abrasive, but more like a polish, knocks down the grit and helps me know if something is not up to par or if I’m just being finicky. When I find myself sanding for more than one minute then I stop and reflect on my choices. Seriously, use a stopwatch. As to re-firing used dinnerware, I’ve done that too (with 20 year old plates no less!). There wasn’t much to lose, those plates were heading to the landfill. It was a sentimental move. Very happy, it was like getting new dishes . No additional glaze, just a refire. I agree with being cautious, slow enough to be positive all water is gone. I’m not advocating it, I just want to be a voice that says “I did that once and it worked well.”

I recently tried firing cone 06 bisque for a cone 10 Bmix set of things. I run a manual propane kiln. Later in the firing I had an issue with my propane tank and was only able to reach 1550F so basically about 200+ degrees lower than needed. Can I rebisque these pieces or will it cause issues?

These seem to be very specific compounds / derivations of mold. Have you considered real mold testing and counts and characterization of mold present in your environment along with indoor air quality measurements. It might quantify and explain this as well as your doctors and hygienist may be able to suggest air filtration as a staple for you regardless of the origination. Most mold originates in the outside environment and then just finds ideal conditions for growth. Testing could reveal your area and environment are conducive to its growth providing some path to minimizing your exposure. Medical grade hepa very likely traps 99% of the spores so this could possibly be something that would help clay or no clay. Mycotoxins may be too small to filter but filtering mold could reduce the potential of specific molds that produce mycotoxins. Anyway, this seems that real certified testing could help point you in a clearer direction than just searching for an origin. Understanding the origin (likely outdoors) and ways to modify your indoor environment (humidity, temperature, filtration) maybe could provide a path to reduction. Understanding if your current outdoor environment is high in these spore counts may also provide another strategy towards minimizing infiltration. My opinion, real air born testing inside and outside your home by a certified hygienist and real lab analysis could provide quantifiable help with your situation. I would measure first and foremost before demolition. Demolishing things can lead to spreading mold around. Most mold remediation is done carefully so as not to spread, then everything is cleaned, hepa vacuumed and new samples and swabs taken before clearing the area.

Is this the original you were using? I've also seen this with 1 rutile.

I have been searching my house endlessly ( 4 years now) looking for mold as I have high levels of both Ochratoxin A and Mycophenolic Acid. Our entire house has been torn up. My office is empty right now and we have torn out a wall to look inside....... and yet no sign of mold or water damage. I have been banging my head against the "literal" wall trying to figure this out and then it suddenly occurred to me that I have an issue in my office and in my bedroom. Both of those rooms have clay on the walls!!!! I have the HLA gene, the MTHFR gene and even the last gene that makes me one of the most sensitive to mold. It is a real thing.

I used Frit 3134 for the boron and modified the quantities of other ingredients to keep the chemistry as close as possible. Same batch of rutile. Here is my latest attempt. 69.4 Nepheline Syenite 14.1 Petalite 8.9 EPK 4.8 Whiting 2.4 Ferro Frit 3134 0.3 Dolomite 0.1 Lithium Carbonate 1.0 Bentonite 2.0 Rutile 1.0 Cobalt Carbonate

Laguna will be carring these potassium feldspars .Mahavir and Vardham from India and G-200 depending on availability

I was interested to find this Australian article https://sydneynorthshoreelectrician.com.au/electrical-service-panel-how-to-calculate-electrical-load-capacity/ ... which contains these sentences It is commonly recommended that the load never exceeds 80 per cent of the capacity of an electrical service panel. and The National Electric Code recommends that the overall capacity of the load does not exceed 80 per cent, ... Which suggest to me that there is no regulation demanding "over-rating" of breakers (at least in that region of Australia). But there are both informal and formal recommendations that this be done - apparently for both continuous and non-continuous loads.