Filament ASA LW UltraFoam dark grey 0.75kg refill Spectrum

Spectrum LW-ASA UltraFoam is a professional technical filament combining excellent UV and weather resistance of ASA with advanced active foaming technology. This unique material enables up to 3x weight reduction of printed parts without compromising strength or surface quality. LW-ASA UltraFoam is ideal for lightweight, durable, and visually appealing prints for outdoor and technical applications where weight and efficiency matter.
The filament is based on the Spectrum ASA 275 formula, enriched with additives for controlled expansion during printing. The foaming process activates around 230°C, with maximum effect achieved between 270°C-285°C. Printing below 230°C allows the material to behave like standard ASA 275.
In its fully foamed state, the filament expands up to three times its original volume, achieving a low density of approximately 0.33 g/cm³. LW-ASA UltraFoam offers exceptional control over material flow, allowing it to be reduced by up to 66%. The degree and speed of foaming can be precisely adjusted by changing the printing temperature, enabling customization of part density. The foaming effect also supports faster 3D printing by allowing thicker layer heights or solid single-wall outlines.
Using Spectrum LW-ASA UltraFoam, significant weight reductions of printed parts are possible - up to 34% compared to traditional ASA, and up to 3x in extreme cases.
The matte and rough surface finish effectively hides layer lines, giving the final part a professional look. The foaming degree influences the material's shade, potentially becoming lighter as expansion increases. The filament retains key ASA features: high UV resistance, dimensional stability, and mechanical durability. It is a perfect choice for projects where every gram counts, such as RC modeling, drone structures, or lightweight functional components.
Key Features:
Over 3x weight reduction of printed parts
Active foaming technology - activated at 230-285°C
Adjustable material density - full control over flow and part structure
Low final density - as low as approx. 0.33 g/cm³
Over 3x more yield - one spool can print as much as three spools of standard ASA
UV and weather resistant - ideal for outdoor applications
Matte finish hides layer lines
Printing Tips:
Foaming level may vary depending on printer model
Higher foaming level can be achieved in enclosed-chamber printers
Moisture negatively impacts foaming - drying the filament before use is recommended
Increasing retraction helps reduce artifacts and stringing
If the model sticks too much to the bed - lower bed temperature, clean the surface, or use an adhesive aid
If the model comes out too brittle, the flow is too low - increase the flow value
How it works:
To obtain the maximum lightweight part, determine the filament's expansion rate.
1. Print a thin-wall test cube with only one perimeter (vase mode) in the 230°C-285°C range, preferably with 5°C intervals. Use the lowest possible fan speed (0-10%), print speed not exceeding 15 mm/s, and significantly lower acceleration and travel speed. Dry the filament before use.
2. Measure the wall thickness of each test model and choose the temperature at which the wall is thickest.
3. For the determined temperature, print calibration cubes, gradually reducing the flow value until the wall thickness equals the nozzle diameter. Typically, the flow should be between 28-40%.
Spool Information:
SPECTRUM ReFill filaments are wound onto an eco-friendly cardboard core compatible with BambuLab reusable spools. This eliminates the need for printing additional adapters. ReFill filaments reduce plastic waste and support sustainable development. A spool print model is available on the Spectrum website if you do not have a BambuLab reusable spool.