3D Printing Startups funded by Y Combinator (YC) 2026

Topological is developing physics-based foundation models for CAD optimization. We help hardware teams iterate at the same speed that software teams do. Our technology is accelerating the engineering workflow with AI and scales design and optimization to identify the ideal designs for complex problems given their physical constraints with enhanced speed and performance. Our first model, UToP-v1, is a SOTA topology optimization model that understands physics, geometry, and manufacturability. It can generate the most efficient design given a problem’s physical requirements. It has <5% compliance error and is 1930x faster than current methods. We're reimagining mechanical engineering and computational design with precision spatial AI.

We are making drone swarms of arbitrary size which are strategically immune to RF interference using phased arrays at 60GHz steered by a novel radar algorithm.

Atum Works is building 3D ASML. Founded by Caltech and NASA engineers, we're starting the next scaling law of semiconductor manufacturing, this time in 3D.

There are 10 million dialysis and bypass surgeries per year, but half of them fail. VenoStent saves lives with a wrap that goes around blood vessels during surgery so they don't fail.

Archform is teeth aligner software startup that lets orthodontists create, design and 3D print aligners within their own offices. The idea is to provide orthodontists with a way to better compete against some direct-to-consumer teeth aligner startups and cut down on the cost of Invisalign.

AON3D is a rapidly growing startup on a mission to put industrial 3D printing capabilities into the hands of those who need it most. Our technology has made it 10 times cheaper than before to 3D print with advanced thermoplastics, and we continue to push the boundaries on commercializing new materials for 3D printing. Our customers span the globe and are pioneers in the application of 3D printing in their field – from automotive tooling to aircraft interiors, foundry molds to public art installations, prosthetics to guides for radiation and surgical oncology. AON3D is a graduate of Y-Combinator and venture-backed by top investors from Silicon Valley.

Relativity is building humanity’s multiplanetary future. We invented a new approach to design, build, and fly our own rockets, starting with Terran 1 – the world’s first entirely 3D printed rocket, and Terran R, our next generation medium-heavy lift fully reusable launch vehicle. As a vertically integrated technology platform, Relativity is at the forefront of an inevitable shift toward software-defined manufacturing. By fusing 3D printing, artificial intelligence, and autonomous robotics, we are pioneering the factory of the future. Disrupting 60 years of aerospace, Relativity offers a radically simplified supply chain, building a rocket with 100x fewer parts in less than 60 days. We believe in a future where interplanetary life fundamentally expands the possibilities for human experience. Our long-term vision is to upgrade humanity’s industrial base on Earth and on Mars.

Layer By Layer is an online marketplace for the buying, selling, and sharing of printable 3D designs. We're going to make it possible to get the things you need and want by printing them yourself, from your own home. We want to allow anyone, technologist or amateur, to be able to use a personal 3D printer - so we decided to create an easy way for people to find and print great products.