PLA Melt

PLA melts

Failed prints, filament scraps, and printed designs are no longer relegated to the recycling bin. Erin Riley, a maker, an educator, and an artist describes what can happen when an artist is surrounded by a new material.

While 3D printer filament can be beautiful in printed form, it’s special properties make it quite versatile when thought of as an art material in it’s own right.

At Greenwich Academy’s Engineering and Design Lab, we have been exploring the properties of PLA, or polylactic acid, as a material for flat and 3D relief painting, forming and melting. PLA is a non-toxic 3D printing filament option that becomes soft and malleable at around 60°C (140 °F) and melts at around 180 °C (356 °F). PLA can act like paint; it can be sticky and viscous when heated to melting temperature and then used for flat design, or can be shaped into 3D forms when warm.

Teacher workshop with PLA melts

At NYSAIS STEAM Camp 2017, a professional development opportunity for teachers, participants had a chance to try their hand at combining scraps and thin pieces of printed PLA.  We offered the raw material for creating PLA melts. This included scraps and thin pre-printed material.


PLA Melts process
PLA scraps and pre-printed materials were the raw material for the compositions.
Pieces arranged on silicone mat , ready for the toaster oven.
Teacher’s PLA after melting (photo courtesy of Anderson Harp).

Materials we used

Filament scraps
Filament scraps are like the canvas drips in an action painting. They could be whatever is in your scrap pile, and when heated, take on a mind of their own. Thin, shredded pieces are easier to fuse, and they twist and turn as they melt.

Pre-printed material
Raft “waffle” and thermoforming structures were printed to use as raw material for creating melted compositions with PLA. Available on Thingiverse, the thermoforming structures are designed by Andreas Bastian and scaled to 170 mm x 170 mm x 0.5 mm.

Beetle Blocks “thins”
2D designs created in Beetle Blocks coding environment make great additions to PLA paintings. Designs are scaled to 0.5 mm thickness.


material for PLA Melts
Beetle Blocks design printed thin for melting

Tools for baking

Toaster oven
For melting PLA, use a toaster oven that will reach 400 °F.

Silicone baking mats
Silicone baking mats can be placed on your oven tray for a non-stick, heat resistant surface. They can also be used to protect your table when melts are cooling.

Oven Gloves
Use oven gloves for safely removing melts from the oven.

Turtle melts

Drawing inspiration from Josh Burker’s work documented in the “The Invent to Learn Guide to Fun,” teachers combined the free-form PLA collage approach, with extruded designs they created in TurtleArt. In our combined workshop at STEAM Camp, Liz Arum guided teachers in preparing files for the 3D printer, slicing models and printing, purposefully keeping the material thin. Thin material prints quickly and responds well to heat.


preparing files
Teacher’s Turtle Art design converted to vector graphic in Inkscape.
Extruded form in Tinkercad.
Sliced model ready to 3D print.


Line Weight/Nozzle size experiments
One teacher’s experiments with line weights and nozzle sizes


Toaster oven


Silicone Mat
PLA on a silicone mat


Teacher Melts
Teacher’s finished Turtle Art melts

Teachers were excited by the possibilities PLA melting offered across a range of subject areas, and could envision potential interdisciplinary connections:

Every step in the process from design idea to 2D shape to 3D form brought forth a design opportunity. From sorting through scraps looking for design possibilities to direct design in vector software, design takes center stage in this project.

The precision of digital tools and fabrication is partially lost when heat is applied to the material. This offers opportunities for serendipity and surprise results.

Calculating and planning the shape design brings together math and the design process when using Turtle Art and Beetle Blocks.

Computer Science
Block-based programming provides an intuitive method for turning design idea into visual output.

Students discover the transformative nature of the PLA material when heat is applied. They experience first-hand the states of PLA, from a solid to a viscous liquid to a glass-like material.