Kiln shelves and kiln posts are often referred to as “Kiln Furniture” and they are a must for every kiln. The size of the shelf and the height of the kiln posts is dependent on the kiln you purchased.
Kiln posts. How many do I need? How many inches should they be apart? Do posts need to be put under molds? What size post do I need and why are there so many sizes?
First, your shelf should be at least 1″ less in overall size than the interior size of the kiln. For example: A 16″ x 16″ chamber of a square kiln requires a 15″ x 15″ square shelf to allow room to insert and remove the shelf easily from the kiln. A 14.5″ octagon shaped kiln chamber accepts a 13″ round kiln shelf.
Second, always get more kiln posts than what your shelf would estimate. They’re really inexpensive, and extremely helpful.
Use kiln posts to elevate your kiln shelf at least ½” to 1” off the bottom of the kiln floor. This allows air circulation for more even heat distribution during firing. A good rule of thumb for how many kiln posts to use depends on the size and type of shelf. Use a minimum of 3 for up to a 14” round shelf for stabilization. The larger the shelf, the more posts you will need to insure it is stable and does not warp. You can never have too many! Kiln posts are also necessary for elevating slumping molds off the shelf, again, allowing air circulation for even heat distribution.
One of the biggest question we get, is, should I use shelf paper or primo primer in my kiln. It is really based on preference. Our recommendation is to try both, and see which you like better.