Can I use chamotte, paper clay or other aggregates?

Aggregates added to 3D printing slurries can be useful for modifying their properties and facilitating the printing process. Here is some specific information about two commonly used types of aggregates:


  • Chamotte, also called grog, is a powder obtained by grinding ceramic materials after firing.
  • It can be added to clay mixtures to modify their properties.
  • It is particularly recommended for large prints to avoid collapse and reduce warping during firing.


  • The name “Paper Clay” is used for clay-based slurries to which cellulose fibers, such as paper, are added.
  • The addition of cellulose fibers can help during printing to reduce the collapse of structures and aid the drying process.
  • During firing, the cellulose fibers burn, leaving porosity in the finished piece.

MAXIMUM AGGREGATE SIZES: The maximum aggregate sizes that can be added to slurries depend on the type of extruder used in your LDM 3D printer:

  • LDM Extruder (version 3.0 and earlier): The maximum aggregate size should be a maximum diameter of 0.2 mm.
  • LDM XL Extruder (version 3.0 and earlier): For this extruder, the maximum aggregate size should have a maximum diameter of 0.5 mm.

Higher than stated particle size values could damage the extruder and cause nozzle clogging during printing.

In general, make sure that the press slurry is smooth and free of debris or hard parts that could impair the flow inside the extruder or on the nozzle. By experimenting with small amounts of aggregates and closely monitoring the printing process, you can determine how to achieve the desired results with your printer.