neilestrick

Have you tried Standard 213? They call it a porcelain, but it's really not. It's basically a smooth white stoneware, similar to B-Mix. It throws and trims well, takes attachments well, and is quite white.

I can't speak to the EU specifically, but here's what I tell about about ceramics programs in the US, which I think will also apply to the EU: There are a lot of good programs, but they are all different. So just picking one that everyone says is good doesn't mean it's a good fit for you. You want professors that are good at the type of work you want to make, but can also challenge you to explore new techniques and ideas. If you're into functional pots, then maybe don't go to a school that focuses on sculpture. The school should have the types of kilns and equipment that you need to explore the types of work you want to make. Some schools focus on gas kilns, others have wood burning kilns, some fire mostly electric. I think there's also something to be said about the location and environment. Some schools are set in a wooded campus, others in urban areas. The location can have a big impact on the vibe of the studio. I've been in many studios that I just wouldn't want to work in, not because they weren't well equipped, but because they didn't feel right to me. Also, there are many good schools that aren't well known. I went to a fairly unknown school that actually had a great program and turned out many good potters. The teaching staff was great and the facilities were good, it just wasn't famous. Last, there's also something to be said for how hard you work. Hard work and dedication to your craft mean as much or more than the supposed quality of the school.

Is the power actually 220V , or is it 240V or 208V? Is 60 the amperage draw of the kiln, or the size of breaker that it needs? What brand and model of kiln is it? Post a pic of the serial plate.

I'd re-fiire them since you don't know how hot they got. The time does not control how long a firing takes to get to temp, it just shuts it down when it reaches 0. You'll need to do a firing with the timer set too long (like 14 hours), see how long it actually takes, and from then on set the timer about 1/2 hour longer than the expected firing time. It's just a backup in case the cone doesn't melt properly.

How long did you let it run? A Slow firing may only climb at 80 degrees per hour, so there won't be much clicking. If you don't want to unload the kiln and run a full power test, just start the firing again and let it run. It'll either work or it will give an error code.

Speedball royal blue is a known problem, especially if thick. Their red does it, too. I use their other blues and reds instead.

No, you don't want this additional vent on the same duct line as the vent, as it will affect the draw of the kiln vent. The fan I linked to needs a 6" duct and the Envirovent needs a 4" duct, so if you wanted only one hole in the wall you could do a single 8" hole and use a Y duct that splits into a 6" and 4". Another option would be the 4" version of the vent, which would allow for a single 6" hole that splits into two 4" ducts. The 4" version has 1/2 the power of the 6" though. The one I have in my shop is fairly quiet, but I don't know the actual db output. If you had a couple feet of flex duct between the motor and the hole that may help to dampen the noise. Not plug the lid hole, but cover one of the holes in the cup under the kiln.

@MochiFriendKilns the size of yours often seal better than bigger kilns, so the air flow can be restricted. My smaller kiln tended to smell a bunch, too. Before opening up the hole in the bottom, add another hole to the lid. If that doesn't help then add another small hole to the bottom rather than make it larger. That way you can plug it if there's a negative outcome from doing that. Another thing you can try is blocking one of the intake holes in the vent cup under the kiln so it will have more pull from the kiln. All kilns will smell during wax burnout, around 500-800F degrees. It's unavoidable. There's just too much burning out for the downdraft to deal with. One thing I've done for a couple of customers and in my own studio is to install a duct fan near the kiln, like THIS ONE. You would need to make a 6" hole through the wall for it and put a 6" cap on the outside just like a dryer vent. You can hang it near the kiln and connect it to the hole with a flexible duct. Keep the window cracked in the neighboring room for makeup air. At up 400cfm it'll help pull out any extra fumes and heat. Plus it's cheap.

Thanks. The angle and lighting of the photo was playing tricks on my eyes. I would say that the size of the ring is at least partially to blame. It's adding a lot of mass to the bottom so you have a wide thin platter with a thick area at the bottom. Clay prefers to be evenly thick throughout. There would be far less stress on the piece if the foot ring was much less bulky, like 1/4" to 3/8" thick. Also be sure you're attaching the ring when the slab and ring are at similar moisture level. It's also possible that the platter cracked or was at least stressed at the lip before it ever went into a kiln, and finally opened up in the glaze firing. But because the crack extends all the way into the foot ring it's probably because of the added mass there.

@weberceramicsCould you post some more pictures? I'm not entirely sure what I'm looking at here in terms of what part of the platter this is- top or bottom, is the ring in the middle unglazed, what's the space between the rings, etc?

@Joe HUsually is the key word here. Most of the time they don't, but if your clear glaze is fluid enough it can cause them to bleed a bit, which is actually a really nice effect in some cases. Black seems to be the most likely to bleed, but blues can do it as well. I personally haven't really seen it happen in other colors, but there are a lot of variables at play.

I've never seen a ribbon cable have this problem without being able to clean it and plug it back in. The question is whether it's the actual ribbon or if it's the connectors on either end, or if it's the board itself. I would contact the manufacturer of the controller, Bartlett Instruments, and see what they say. I don't think they have capped end so that may very well be an option. There is no locking tab or anything like that, you just push it in.

Mug rims need to be rounded, and you should never sponge the rim or it will get rough (if you're using stoneware). The sponge removes the fine particles in the clay and exposes the larger particles. If you do have to sponge it, go back over it with your finger and a tiny bit of water. Also make sure the lip has a good glaze layer. A thin rim is more comfortable to drink from, but too thin and it won't take glaze well, especially if you're dipping, because it can't take in enough water to leave a good deposit of glaze.Too thin a glaze layer and it'll feel rough.

@midsomerjambo I've edited your post so the text is in post instead of an attachment.

Cleaning the ribbon connector is usually the solution for that. Could it be that it's working its way loose somehow? Is it in a very humid space? Really high humidity can make them behave weirdly, too. Beyond that it may be time to replace the panel. How old is it?

Congrats! If one of the switches goes out again, replace them with 240V infinite switches with the element pairs wired in series. Better control, simpler wiring. Have fun!

I would order whatever you want from an online source. I'm a big fan of Speedball underglazes.

I'm assuming that since you suggested firing it to cone 10 that it's rated to cone 10? There's a couple of problems with firing it to cone 10. First, it'll only get there for maybe a couple dozen firings before the elements need to be replaced. Second, since you're probably firing the gas kiln in reduction, the results won't be the same because the electric kiln can only fire in oxidation. It would be better as a cone 6 kiln for test tiles or when someone needs just a couple small pieces fired, or for jewelry. We use my baby kiln all the time. You'll get 100+ firings (bisque and cone 6 glaze) from a set of elements. The problem is that it will cool much faster than a larger kiln, so you really need to slow down the cooling to get the same results, which is difficult in an electric kiln. The only way to do it is to be there when the firing ends, and restart the kiln on medium instead of high. Run that for about 3 hours then shut it off. If it's in good condition it might be worth buying a digital controller for it so you can program it to match the heating and cooling cycle of the larger kilns.

I describe underglazes as being somewhere between a slip and a glaze. They melt/fuse more than a slip, but don't don't totally melt into glass like a glaze. Also, commercial underglazes can be applied at any stage of the process- wet, leather hard, bone dry, or bisque. When to apply them depends on how you're using them and the brand you're using.

That type of crack is likely to continue to get worse, especially in the glaze firing. Sometimes it's best to just move on and make another one.

Knowing this, firing hotter should allow the glaze to take the copper into the melt and go green. I don't know how the cooling will affect it, but I expect if it went glossy green it should stay that way with a fast cooling. The question will be whether or not it will respond the same in a refire as it does in a first firing. Nothing to do but test it!

Lots of possibilities here, but it all comes down to you can't expect a glaze to do the same thing in a totally different kiln. First, wood kilns don't just fire in oxidation. They cycle between oxidation and reduction every time the kiln is stoked. Second, you've got a different atmosphere in the wood kiln due to ash and vapor from the wood. Third, the temperature was different, but maybe not depending on where it was placed in the kiln. Fourth, the cooling cycle was different. Different clay body? At this point I would hold off on refiring your pitchers and instead run a couple of test firings with other pieces at a higher temp and with a slower cooling cycle and see if you get the desired results. Once you've figured out what's needed, then refire the pitchers and hope they do okay with refiring. In meantime I would also start making a new batch of pitchers and offer your client a different color that you know will come out as intended. FYI, many of us, including me, have been in a similar situation at some point.

Any fix on bisque is a gamble. If it's applied to the surface it will probably flake off. In the crack it will probably hold if the crack doesn't get bigger, but it can't prevent a crack from growing. Whether or not a crack grows depends on what caused it in the first place. Post pics.

No worse that any other forced air system. Follow basic cleaning guidelines (wet cleaning- mop, sponge, etc) and you shouldn't have anything to worry about.

It would take an awful lot of toilet paper to make the mold lighter. In Peter's link she's using paper pulp, which would be much easier to add in a volume that would actually make it lighter. I agree that it may affect how absorbent the mold is, but you'd have to do a comparison to see. FYI the 7:10 ratio is for #1 pottery plaster. Other types of plaster require a different ratio.