How to build (and rebuild) with glass

Stern and Kaitlyn Becker ’09, an assistant professor of mechanical engineering and another coauthor, got the inspiration for the bricks partly from their experience as undergraduates in MIT’s Glass Lab.

“I found the material fascinating,” says Stern, who went on to design a 3D printer capable of depositing molten recycled glass. “I started thinking of how glass printing can find its place.”

“I get excited about expanding design and manufacturing spaces for challenging materials with interesting characteristics, like glass and its optical properties and recyclability,” says Becker, who began exploring those ideas as a faculty member. “As long as it’s not contaminated, you can recycle glass almost infinitely.”

For their new study, Becker, Stern, and coauthors Daniel Massimino, SM ’24, and Charlotte Folinus ’20, SM ’22, of MIT and Ethan Townsend at Evenline used a glass printer that pairs with a furnace to melt crushed glass bottles into a material that can be deposited in layered patterns. They printed prototype bricks using soda-lime glass that is typically used in a glassblowing studio. Two round pegs made of a different material, similar to the studs on a Lego brick, are incorporated into each one so they can interlock. Another material placed between the bricks prevents scratches or cracks but can be removed if a structure is to be dismantled and recycled. The prototypes’ figure-eight shape allows assembly into curved walls, though recycled bricks could also be remelted in the printer and formed into new shapes. The group is looking into whether more of the interlocking feature could be made from printed glass too.