Phone: +1 (855) 994-2233 | Location NH/NV: 9:00 am to 5:00 pm M-F
Loading Your Kiln For a Bisque Fire
The primary purpose of a bisque fire is to remove water from the clay, break down organic materials, and turn the clay into ceramic, making the piece more durable and ready to accept stains and glazes.
How do you know when the clay is ready to be bisque? Well, there are several ways, but the easiest by far is to place the pot against your cheek. If the pot is still cold, it's not ready... if it's about room temperature, it's ready to go.
Here are some tips on loading your kiln for a bisque fire. On Friday, we'll go over what to do once you remove them from the bisque fire, and how to prepare them for that final step... the glaze firing!So, you've checked all the pieces you want to bisque, and they are "bone dry." What's the next step? Load them into the kiln.
Preparing the kiln...
- Make sure the kiln is clean. Vacuum out all debris from previous firings, including the element channels.
- Bottom shelf should be placed on 1/2"-1" posts to allow for heat circulation.
- All kiln furniture (posts, shelves, stilts etc...) should be kept at least 1" from the elements.
- Kilns shelves should be properly coated with kiln wash
A few notes on loading...
- You need to be VERY careful loading bone dry pieces into the kiln. This is the most fragile state of the clay... one slight bump can ruin the entire piece. Don't pick pieces up by the top or by attached handles, always pick them up from the bottom.
- Having a full kiln isn't always necessary however; it is much more cost effective.
- Bisque pieces can be stacked on top of each other for this step, but stacked too high or tight can cause problems, so use caution not to overload the kiln.
- Large plates, platters and bowls warp less if they are placed in the center of a shelf. This allows for more even heating.
- Make sure you place the witness cones on a shelf near a peep hole for easy viewing. Witness cones should be used even if you use a kiln sitter or electronic controller.
- Items with lids should be fired with the lid in place to assist in even expansion and contraction and help ensure a proper fitting lid.
- Don't allow pots or kiln furniture to touch the walls of the kiln. There should be at least 1" between them.
- Load shorter pieces on the bottom shelf and increase the size as you move up if need be as shelves are more stable on smaller posts.
- When placing posts on the shelf, they should be placed directly over the posts on the shelf below.
- Allow 1/2"-1" of space between the top of your pots and the next shelf, and the same amount between the top of your pots and the kiln lid.
Once you've loaded the kiln, close the lid and let the firing begin. Refer to your kilns manual for firing instructions.
Questions or comments? Email us at email@example.com.