neilestrick

I've always used the SUV I drive everyday. For the last 7 years that has been a 2012 Nissan Pathfinder. Before that a 2011 Chevy Traverse. Before that a 1998 Pathfinder which was a little smaller than ideal- I had to strap stuff to the roof rack. Some use vans, some use pickups, some use a trailer.  Deciding what works best for you depends on your booth setup, how much work you'll be taking to shows, costs, etc. HERE is a little article I wrote on the subject.

I said 'properly formulated'. There are commercially produced cone 10 bodies that have greater than 2% absorption, too. There is nothing about cone 10 that makes work any more durable or functional or safe to use. It's just hotter. That's it. Regardless of the temperature you're firing at, you can make vitrified, durable, safe pots.

Probably a combination of their glaze choices, firing technique, and clay choices.
Cone 6 clays are also vitrified. There's no difference, assuming both are properly formulated.
 

Probably a combination of their glaze choices, firing technique, and clay choices.
Cone 6 clays are also vitrified. There's no difference, assuming both are properly formulated.
 

The glass has a  very different COE (coefficient of expansion- different shrinkage) than the clay and glaze, and it most likely put a ton of stress on the coasters and blew them apart.
To get the piece off the bottom, try sliding a pallet knife/scraper under the chunk. You may lose a little bit of the floor but that won't hurt anything. If it has melted into the floor a bit, put a thick layer of kiln wash on it for the next few firings until it stops melting.

A ball point pen works well, too.

The slip has not moved. The color of the brown clay is coming through the slip where it is thin. You need more coats of slip.

A ball point pen works well, too.

A ball point pen works well, too.

If your white slip is a porcelain body then it might be somewhat translucent, so a thicker layer is needed to make it more opaque. Plus the iron in the dark clay is pretty powerful stuff and will tend to darken just about anything put on top of it that's not very opaque.

The slip has not moved. The color of the brown clay is coming through the slip where it is thin. You need more coats of slip.

The glass has a  very different COE (coefficient of expansion- different shrinkage) than the clay and glaze, and it most likely put a ton of stress on the coasters and blew them apart.
To get the piece off the bottom, try sliding a pallet knife/scraper under the chunk. You may lose a little bit of the floor but that won't hurt anything. If it has melted into the floor a bit, put a thick layer of kiln wash on it for the next few firings until it stops melting.

The glass has a  very different COE (coefficient of expansion- different shrinkage) than the clay and glaze, and it most likely put a ton of stress on the coasters and blew them apart.
To get the piece off the bottom, try sliding a pallet knife/scraper under the chunk. You may lose a little bit of the floor but that won't hurt anything. If it has melted into the floor a bit, put a thick layer of kiln wash on it for the next few firings until it stops melting.

In addition to the potential band issue, if the outer dimensions are not the same then your control boxes are not going to line up properly. I also think it's going to affect how the kiln heats. If you had zone control it wouldn't be an issue, but with just one thermocouple the 2 1/2" section is likely to run colder than the 3" section. Plus the overall energy savings would be minimal since the lid and floor would still be 2 1/2" brick.
What does it say on the serial plate for the max temp rating of the kiln? If I remember correctly, the 181 is only rated to about cone 5/6, which is the biggest reason it's struggling to reach cone 6. You're maxing it out, and you're not going to get very many firings before it won't reach cone 6 at all, like maybe only 30 firings.

The glass has a  very different COE (coefficient of expansion- different shrinkage) than the clay and glaze, and it most likely put a ton of stress on the coasters and blew them apart.
To get the piece off the bottom, try sliding a pallet knife/scraper under the chunk. You may lose a little bit of the floor but that won't hurt anything. If it has melted into the floor a bit, put a thick layer of kiln wash on it for the next few firings until it stops melting.

The slip has not moved. The color of the brown clay is coming through the slip where it is thin. You need more coats of slip.

The slip has not moved. The color of the brown clay is coming through the slip where it is thin. You need more coats of slip.

Those dangling elements should be replaced, otherwise they're going to contact the work in the kiln and cause problems. You'll also have to replace those broken bricks or else the elements are just going to flop out again. Neither is super difficult, but if you've never done it before it'll take some time. You'll spend $65 per element and about $17 per brick to fix it. HERE is a video that shows how to replace bricks. HERE is a video showing how to replace elements.
I would pass on that kiln if you don't have experience with repairs. If I remember correctly, the 231 has the old style control boxes with the early generation Kiln Sitter, which is not ideal, and not easy to work in.

Those dangling elements should be replaced, otherwise they're going to contact the work in the kiln and cause problems. You'll also have to replace those broken bricks or else the elements are just going to flop out again. Neither is super difficult, but if you've never done it before it'll take some time. You'll spend $65 per element and about $17 per brick to fix it. HERE is a video that shows how to replace bricks. HERE is a video showing how to replace elements.
I would pass on that kiln if you don't have experience with repairs. If I remember correctly, the 231 has the old style control boxes with the early generation Kiln Sitter, which is not ideal, and not easy to work in.

I would try a cone 5 firing, on medium or med-fast. Slow is not necessary. Your glaze is probably over-fired, however bisque firing cone 04 might help.

I would try a cone 5 firing, on medium or med-fast. Slow is not necessary. Your glaze is probably over-fired, however bisque firing cone 04 might help.

Those dangling elements should be replaced, otherwise they're going to contact the work in the kiln and cause problems. You'll also have to replace those broken bricks or else the elements are just going to flop out again. Neither is super difficult, but if you've never done it before it'll take some time. You'll spend $65 per element and about $17 per brick to fix it. HERE is a video that shows how to replace bricks. HERE is a video showing how to replace elements.
I would pass on that kiln if you don't have experience with repairs. If I remember correctly, the 231 has the old style control boxes with the early generation Kiln Sitter, which is not ideal, and not easy to work in.

The slip has not moved. The color of the brown clay is coming through the slip where it is thin. You need more coats of slip.

The simplest and most affordable way to fire is with an electric kiln. They are easy to use, easy to set up, can be installed in basements and garages and studios. They don't take up much room and are easy to vent. Firing to cone 5/6 you'll have durable, vitrified pots for food use, and there are hundreds and hundreds of commercially available glazes.
What type of kilns are used at your studio?

The simplest and most affordable way to fire is with an electric kiln. They are easy to use, easy to set up, can be installed in basements and garages and studios. They don't take up much room and are easy to vent. Firing to cone 5/6 you'll have durable, vitrified pots for food use, and there are hundreds and hundreds of commercially available glazes.
What type of kilns are used at your studio?