Burr is an imperfection or excess material that appears at the edges and joints of ceramic pieces, especially those that have been created using molds or casting techniques. These bumps or residues usually form when liquid or wet material, such as slip, seeps through the mold joints, leaving lines or accumulations of clay once the piece is demolded. They can also be generated during the cutting of the clay in manual techniques if the tools are not used correctly.
Removing burrs is a fundamental step in the preparation of the pieces before drying and firing. If not removed, burrs can harden and become permanent defects that affect both the aesthetics and functionality of the part. In some cases, burrs can create stress points that cause cracks or breaks during firing.
The removal process is done with tools such as ceramic knives, wet sponges or even sandpaper. The smoothness of the finish is crucial to prevent the final piece from having rough or sharp edges that may be uncomfortable or dangerous to use.
Interesting Fact
In modern industrial ceramics, burr removal has been practically automated thanks to the development of high-precision molds and assisted demolding technologies, allowing parts to be produced without the need for extensive manual work at this stage.
Helpful Tip
Remove burrs while the piece is still wet or leather-hard, as it will be much easier to smooth the edges at this stage. Use a damp sponge after removing burrs with a blade to completely smooth the surface and prevent the burrs from reappearing when dry.
