At colorFabb, material development never stops. We’re introducing a fascinating new material, first of its kind, in FFF 3D printing materials.

We’re proud to announce, colorFabb LW-PLA. This filament uses an active foaming technology which is triggered by temperature. At it’s peak the filament will expand nearly 3x it’s volume, meaning users can decrease flow by 65% to obtain lightweight parts, or use the expanding properties to speed up print time by using big layer heights or single extra thick perimeters. colorFabb LW-PLA is available in two colors, natural and black. The foaming also gives printed parts a rough matte surface finish, which makes parts look very appealing.

For the filament to expand it is necessary to put a certain amount of energy into the filament. The amount of energy a filament can absorb during printing depends on the length of the hot-zone and the time it takes for the filament to pass through the hot-zone. The longer a filament will reside inside the hot-end, the more energy it can absorb which will increase the amount of expansion. Assuming nozzle size and layer-height are fixed, our main input variables are Temperature, speed and flow to determine the amount of expansion.

To print lightweight parts, which are dimensionally accurate, it’s important to first determine the possible expansion of the material. This can be done by printing single perimeter test cubes without top and bottom layers. Use the following 4 step process to determine the maximum expansion at a certain speed, temperature and flow.

  1. Print cubes at a set speed in temperatures varying from 200°C up to 280°C
  2. Measure perimeter thickness of each cube, note temperature with highest expansion
  3. Print cubes with decreasing steps of flow, using temperature found in step 2
  4. Find the cube at which perimeter thickness equals nozzle size

Lightweight printing can be done by using the settings determined in the paragraph above. Keep in mind that if the flow is decreased to low values the hot-end might clog due to the filament expanding before exiting the nozzle.

On the left we printed the same gcode using regular PLA, on the right our colorFabb LW-PLA showing the expanding properties enabling 0.6mm layerheight from a 0.4mm nozzle.

Due to the expanding behavior of the material it is possible to 3D print with larger layer heights the nozzle itself, this means short build times for quick draft models.