neilestrick

I'd give another inch of width in the firebox, then just center the shelves in the space. What diameter is your burner port?

It depends on if you're firing in reduction or oxidation. In reduction, 4% iron will make a huge difference. In oxidation, not so much.

I agree with Callie. The costs will be specific to your operation because of differences in rent, utilities, and what you're able to charge per student. It's just going to be a matter of crunching the numbers there. I can tell you that the one thing my students really like, compared to other studios, is that once they've paid for an 8 week session, there aren't a bunch of little fees that nickel and dime them to death. Tuition charge cover open studio time, too. Clay prices include glazing and firing. If you want them to keep coming back, don't make them feel like it costs them every time they walk in. It's also a lot easier for me as the owner to not have to be dealing with the money all the time.

I agree. Don't just add red iron oxide. It tends to make the body more brittle and doesn't disperse well. You're better off adding a red clay. Any red clay can work- Redart, Newman, etc. See what your local clay supplier has in stock.

I don't think I've ever seen a downdraft vent last less than 5 years now that they don't mount the motors under the kiln. I've got 11 years and 2000 firings on one of my downdrafts. Vent-A-Kiln hoods seems to last forever. All of the kiln vents on the market work very well. I think the've struck a good balance between ease of installation, functionality, and price. Yes, you can build a better system for less money, but for the average customer it's a good, simple solution to the venting problem.

I'm really stumped. The only reason a cone should break is if there was some pressure put on it. Just to be sure you're doing it correctly: 1. Lift the weight 2. Push down the claw, which raises the sitter rod and holds the weight in place 3. Place the cone

I'm talking about downdraft vent fans that were installed to manufacturer's instructions- Skutt Envirovent, L&L Vent-Sure, Orton Ventmaster, Vent -a-Kiln hoods, etc. The fans are completely corroded when they die, from the fumes and moisture from the kiln. For CeramicJim, the more clay dust he sucks through it, the shorter its lifespan. The more firings he uses it to vent, the shorter its lifespan. It could very well be that there are better ways to design the systems, but for most people that's not an option, because most people don't have a background in HVAC installation. Plus the lifespan of a vent fan is about number of firings, not number of years. If you only fire once a week, your vent system will last a lot longer than someone who fires 5 times a week.

I was referring specifically to fans used for venting kilns and studio dust, like what was described above, not ceiling fans or jet engines. If the fan was just pulling air through it I would agree that it should last a long time. But when it's pulling abrasive clay dust, moisture and fumes from the kiln, etc, it's going to affect the life of the fan. I've replaced enough kiln vent fans to know that they don't just wear out due to age. They corrode.

Agreed. Do not use that plug. If you twisted it back, it would be in the original 20 amp position. It's not about the voltage. You cannot use a 20 amp plug in a 15 amp outlet. You should not use an adapter, either, because it would overload the circuit to run a 20 amp kiln on a 15 amp circuit.

@Elise Try putting a small amount of kiln wash on the bars that the cones rests on. Just enough to make a barrier between the cone and the bars. I wonder if the cone is sticking to the metal, and snapping as it heats and expands. Does the kiln turn off when the cone breaks? How hot is it getting?

It won't harm the kiln to fire it to cone 6, it's just that you won't get very good element life from it. Usually we fire to cone 6 in kilns that are rated to cone 10 because the elements can wear more before the kiln can't reach cone 6. If you're firing to the max of the kiln, then you have to change the elements once they wear just a little bit.

The drawing is not accurate no matter what's going on with the wheel head. A bent shaft would not allow it to happen, either.

If the prong was twisted 90 degrees, then he was trying to make it fit a 15 amp outlet instead of a 20 amp outlet, not 110 to 115 volts. 20 amp outlets have one prong turned perpendicular to the other so that you can't plug a 20 amp appliance into a 15 amp outlet, because that would overload the outlet. According to the Skutt website, that kiln pulls 20 amps, which means it should actually be on a 25 amp breaker, because code requires that kiln be on a breaker that is 25% greater than the draw of the kiln. I would also put a cord on it that is rated to 30 amps. Also, according to the Skutt website, that kiln can only go to cone 6, so it's not ideal for doing cone 5/6 work. You'll be maxing it out every time you fire it, and once the elements wear even a little bit it won't get to temp.

The longevity of a fan varies greatly depending on environmental conditions. Saying it will last for X number of years is impossible, but it should last for at least several years. However now that you've done all the hard work, replacing it in the future will be much quicker. When venting heat and fumes from a room, it's all about how quickly/often the air in the room is changed. When sizing a fan, HVAC folks do calculations to size the fan to the both the size of the room and the amount of heat given off by the kiln. There are standards that they shoot for in their calculations. Your system may work very well for your situation, but a 185CFM fan may be terribly undersized for someone with a larger room or a larger kiln. Just as a point of reference, Vent-A-Kiln hoods use a 265CFM fan on hoods for 23" wide kilns.