Hand-bent stool after 3D printing with LW-PLA

The idea behind the stool & working with LW-PLA's material behaviour

The starting point was to challenge how 3D-printed furniture is typically made. Most printed chairs are extruded as a side-view profile, with the machine building the shape vertically, layer by layer. We wanted to break that norm. By printing flat and then heat-bending into the final form, we're using the process differently, finding new ways to work with the properties of 3D printing rather than simply accepting the default approach.

LW-PLA plays a specific role here. The inner layers are printed at higher temperatures to activate the foaming process, significantly reducing weight. The first and last layers are printed at lower temperatures, remaining solid. This creates a harder, more durable surface while also producing a visible colour shift between the dense outer shell and the lighter foamed core. That gradient isn't just structural; it becomes an aesthetic detail that reveals how the object was made.

The bending itself isn't about the material's chemistry; it's about how we print. In the bend zone, the toolpath splits into separate lines rather than solid infill. This allows those areas to heat faster and more evenly, turning the print pattern itself into an indicator of where the fold happens. The structure tells you how it wants to move.

Why this project called for LW-PLA

Our collaboration with colorFabb started with a shared curiosity to explore the possibilities of LW-PLA FGF pellets. We were immediately interested in the weight reduction and the ability to build volume with less material. On a large-scale printer, that matters a lot.

The project started with the material itself. We began by exploring what LW-PLA could do, and the stool evolved from there. That's often how we work: letting the material's properties guide the design rather than forcing a predetermined form onto a new material.

Just by controlling temperature...

We don't use a slicer. We code the toolpath directly, controlling temperature, speed, and extrusion rate line by line. This let us fine-tune exactly where the material foams and where it stays solid.

The result is a stool with two distinct zones. The inner layers are printed hotter, activating the foaming reaction. They come out in a light pink with a crispy, matte texture. The top and bottom layers are printed cooler, staying dense, with a deeper red colour and a shiny, almost mirror-like surface. That contrast isn't just aesthetic: the solid outer layers add strength and durability, while the foamed core dramatically reduces weight compared to standard PLA.

So in one print, with one material, we get both the structural performance and the visual expression we wanted, just by controlling temperature.

What is the overall experience printing with LW-PLA?

Surprisingly easy. We started from an article by CNC Kitchen, dialed in the settings a bit, and it just worked. No clogging, no stringing, consistent behaviour throughout.

For a material with such active properties, the foaming reaction, the temperature sensitivity, we expected more trial and error. But it was straightforward to get reliable results. The surface quality is excellent, and the overall experience felt premium. We'd recommend it without hesitation.

How did the LW-PLA respond during the heat-bending process? Did the material behave differently than they expected?

This was our first project using this print-flat-then-bend approach, so we didn't have a direct comparison. But it worked more or less as we anticipated. The bending points are built into the geometry. The toolpath splits in those zones, so the material heats faster there and naturally wants to fold at those spots. It can't really bend anywhere else.

Both the foamed and solid sections behaved the same during bending, which made the process predictable and controllable. No surprises. It just did what we designed it to do.

The difference LW-PLA makes

Mainly weight and aesthetics. The bending process would work with other materials, but the stool would be significantly heavier. At furniture scale, that weight difference matters for handling, for transport, for how the object feels when you pick it up.

The aesthetic is unique to LW-PLA. The colour shift between the foamed core and the solid outer layers comes from the trapped air in the foam. It physically changes how the material absorbs and reflects light. You can't get that effect with standard PLA. It's not applied, it's structural.

How do you see this material exploration evolving in the next stage of the project?

We developed the design into a dining chair for our exhibition with UKURANT at 3 Days of Design 2026. Adding a backrest and refining the details allowed us to further develop the concept.

We want to expand the concept into other typologies. We'd love to see a table using the same print-and-bend approach: legs made with this technique, topped with a large glass surface that lets you see and appreciate the construction underneath. The transparency would make the process fully visible, how the material folds, where the bending points are, the contrast between foamed and solid zones. That's the direction we're excited about.