Rockhopper

As Mark said - you need to find out how much power (how many watts or amps) your kiln uses - then ask your electrician if the circuit (wiring, breaker, and outlet) can handle it. Using an adapter to connect a 50-amp plug to a 30 amp outlet could be very dangerous - as-in, start a fire inside your walls dangerous - if the wiring is too small for the amount of current being pulled through it.

How big is your shed ? Are you planning on firing in it - or will it be just for 'potting' ? Is your shed well vented ? The best way to prevent, or at-least minimize condensation is to remove the moisture from the air. Even relatively warm, well insulated walls can sometimes get condensation on them in cold weather, if the inside humidity is high enough and/or the space isn't properly vented. If you have electric in your shed, you might want to consider a de-humidifier. (The less moisture there is, the colder the walls & roof have to get before it will condense.)

What Bill mentioned is definitely important to keep in mind: When you're looking at pictures of glazes, or sample pieces on display in a pottery supply shop, be sure to note the type and color of clay used for the sample piece. For example: Many of the layering examples on Amaco's site are done with a light colored buff stoneware - and will not look the same on a different color or type of clay. What firing range are you working with ? I've seen a lot of under-glazes in small jars, and some low-fire glazes - but if you're doing mid-fire (^5-^6) range, you'll probably have a hard time finding containers smaller than a pint. (At-least it's that way in the US. Could be different where you are.) Might be worth checking around your area for a studio or community center that offers 'open sessions', where you could have access to an assortment of glazes to try, without buying full jars of them.

What cone do you plan on firing to ? This is a critical factor in selecting both clay and glazes.

There is probably no 'food-safe' way to fix a leaky mug without re-firing - and even that is iffy at best. I've had some success sealing a 'weepy' vase, by coating the inside with water-based polyurethane - but definitely would not do that with anything I'm going to use for food/drink. I would suggest contacting the potter that made it and see if they will replace it. I wouldn't want someone to show one of my mugs to a friend and say "I really like this mug that Jim made - but I can't use it, because it leaks". I'm betting most potters would feel the same, and would happily exchange it.

What is the recommended cone range for you clay body ? If you're firing at the upper end, maybe firing just a tad cooler would stop the slumping, but still be 'mature enough'. Could be that there's some interaction between clay & glaze that is lowering the melt point of the clay - especially if, as others have suggested, it's a little on the thin side. I was doing some testing of local clay several years ago, and fired identical pieces side-by-side, with one un-glazed, and others with various glazes, and a couple of the glazed ones slumped badly, when the un-glazed piece didn't move at all.

Good has been out of business for many years. (Actually bought out by another company, that later went out.) I had one of their kilns, that had rotary 'High-Med-Low-Off' switches... As you've probably already found - Kiln-Sitter manuals are readily available, but I never did locate any sort of manual for the kiln itself. I played around a little with different combinations, to try to even out the firing from top to bottom - but most of the time I just went with all on low for two hours, med for two hours, then high 'til the sitter trips. Depending on how full the kiln was, a small ^6 on the sitter gave me what I would call a ^5+ (Self-supporting witness cones ^5 full down & ^6 slightly bent.) If your controls are something other than H/M/L/O, let us know what you have and/or post a couple pic's of the controls, and you may be able to get more specific suggestions. PS - If you change the 'title' of your post to something like 'Seeking info on JW Good Kiln' - you may get a better response

And you've also learned that applying clear glaze over whatever paint you used probably wouldn't have worked either... On the plus side, if you've only fired to bisque temperature, you can probably start over on the same piece and decorate with under-glazes this time - with a top-coat of clear glaze if you still want to do that.

If you're looking to remove just the Mod-Podge, you're probably out of luck, unless you 'painted' your piece with under-glaze. Firing to burn off the Mod-Podge will most likely also burn off whatever paint you applied under it.

What clay body are you using ? Clay color & composition will affect glaze results. Most of the sample pic's on Amaco's website use a buff-colored stoneware. If you're using a darker clay, you won't get the same results - especially on some of the more transparent colors. Also - "thick" can be a pretty subjective term. What you see as a 'thick' coat might not be as thick as on their samples.

If you're looking at commercial glazes, Coyote's Bronze Temmoku might get you close but, as Callie indicated - application and firing (and clay body) will affect results. This pot is Standard's 112 (speckled brown), with 3 brushed-on coats of glaze, fired to apprx ^5-1/2. (The small spots that look a bit like water spotting, are from the 'speckles' in the clay and, presumably, would not be there on a non-speckled body.)

I'm 5'11 - so reaching the bottom of a 27" kiln wasn't really a problem, but lifting shelves & pots from the bottom was a bit of a strain on the back. When I replaced my old 18x27 kiln, I decided I didn't need the 27" depth, and went with an e23S - but I built a taller stand, so the the bottom is higher, and the top is about the same height above floor as the 27". I now have a wider kiln, with slightly more volume, that's easier to load & unload, because I don't have to stretch as far to get to the bottom. (Kind-of like picking things up from a coffee table, instead of the floor.)

When you say 'completely flat' - do you mean they held their shape, but bent over, like they are laying on their side - or did they melt completely into a puddle ? (pic's might be helpful) Have you had successful firings with this kiln in the past ? If yes, look for what may have changed since the last successful effort: Any chance you got 04, 05, and 06 cones, instead of 4, 5, and 6 ? Could the cones have gotten wet since the last time you used them ? Did you accidentally add a soak to the end of your firing ?

There's a phrase that pops up frequently on the forums, with regard to glazing and other "will this work' questions: "Test, test, test". If you have a known sensitivity to specific types of mold, you could have your clay - and maybe the air and surfaces in your studio - tested to see what is there. Then, once you know what you are (or are not) dealing with, you can make better decisions about how to proceed. As Neil suggested - a 'musty' smell in the studio is more likely to be due to moisture problems in the room/building than from the clay itself. As clay dries it release a lot of water into the air. If the space is tightly sealed and/or has concrete walls or floors that are cooler than the air, that water will condense on those surfaces - creating a perfect environment for mildew and other fungi to thrive. The solution could be as simple as a thorough cleaning - and installing a good de-humidifier.

I realize each supplier is different - but it's definitely worth trying Neil's suggestion. Depending on how often they order, you might have to wait a while - but they should be able to add a box or two of whatever you want to their stock order, as long as it's available from wherever they're buying their clay.