Q: Does CAC repair kilns?
A: You betcha! We have loads of experience working on kilns and other equipment. Commonly we see people bring in used kilns that they want to have brought back to original working condition or have basic maintenance performed. We are certified SKUTT repair techs and we can also service kilns made from the other leading manufacturers as well. Parts availability is limited to what is on hand and ordering parts from the manufacturer may be necessary; typically we have most parts for SKUTT on hand.
Please visit our Kiln Repair page for the most up to date info
Q: My brand new kiln has cracked or chipped firebrick, is this a problem?
A: Firebrick is very delicate and easily damaged. Often times there may be hairline cracks in the brick even on brand new/never opened kilns. This is normal and not cause for alarm, it is purely cosmetic in most cases and can be patched if desired. In the event that you have more considerable damage we will advise you on the best method of remedy.
Q: I see that you sell 2.5" and 3" firebrick kilns, what is the difference and what is best for my needs?
A: If it were up to use everyone would be buying 3" kilns. We find that they are more efficient to heat and work better for most situations. A 2.5" kiln would be ideal for folks doing low fire work where they need faster cycling times. Your shelves will often be slightly bigger for a 2.5" kiln which will increase their cost when compared to the 3" sizes.
Q: What is Kiln Wash and do I need to use it?
A: Kiln wash is made of refractory substances, like silica, alumina, or zirconium, that have high melting points and don’t cause melting when combined. The exact formula is adjusted based on an artist’s intended firing temperature; silica is typically used in low- or mid-fire temperature ranges, while alumina, which is sourced from kaolin, the foundation of porcelain clay bodies, is typically used for higher temperatures since it has a higher melting point.
Kiln wash provides a protective layer between your artwork and your kiln shelves. Though glaze is never intended to come in direct contact with kiln shelves - hence, why stilting or wiping glaze off the bottom of a project is important - sometimes it will unexpectedly run, spit, drip, or melt onto the shelf. Long story short, kiln wash protects your investment in shelves and is highly recommended!
We produce a standard version of Kiln Wash and we also produce a version called Z-Tech which is less prone to flaking off when flipping shelves and also will leave very minimal pockmarks when something does stick which facilitates easy reapplication of Z-Tech to only the problem spot.
Q: How do you apply kiln wash?
A: If you bought dry kiln wash you will need to mix it before application. Add water and mix to the consistency of buttermilk, just mix enough for the job. If using pre-mixed just shake and coat!
- Fire new kiln shelves dry. Before even mixing your kiln wash, if you are using brand new kiln shelves, it is recommended you first fire them once in an empty kiln. This initial step will drive out any organic material from manufacturing and transport. Now they are ready to have kiln wash applied.
- Mix a small amount of wash in a bowl. Mix some of the powder with water until it has the consistency of skim milk.
- Apply thin coats. Using a wide paintbrush, utility brush, roller, or even sprayer, apply a thin layer of wash to the kiln shelf. If the coat is too thick, it could cause more cracking and peeling. Also, be careful to avoid getting kiln wash on the edge of the shelf; it can flake off during firing and onto your glazed pieces below. Many artists sponge off a half-inch of kiln wash around the perimeter to ensure it won’t go over the edge.
- Apply at least 3 coats of kiln wash. To ensure that there is enough protection between your ware and the kiln shelves, you should apply three full coats of kiln wash. Let each coat dry thoroughly before applying the next one - allow about 60 minutes per layer. Some artists even chose to fire between the application of each coat, building it up during bisque firings or adding additional layers during glaze firings.
- Scrape any wash that flakes off. If you notice that your kiln wash is flaking, remove any loose pieces with a paint scraper and reapply. Similarly, if any glaze drips onto your shelf, use the paint scraper to remove it, clean up any loose flakes around it, and then dab some kiln wash on the bare spot.
Q: I bought some CAC Plum Black or Aardvark Obsidian black clay and I want to fire it, is there anything I should know first?
A: Obsidian is a beautiful black mid-range stoneware and it has some specific considerations to make when firing. We recommend what is called a Oxidized Bisque firing, which means that you want to fire with all of your peep holes open which will help make sure all organics are fully burnt out. Additionally this clay should not exceed Cone 5 when glaze firing as it will bloat, bloating is even more of an issue if you don't do the oxidized bisque. Use witness cones and make sure you know how your kiln fires to compensate if need be.
We recommend you read Steve's Oxidized Bisque for a more in depth understanding of this process.