UC Berkeley researchers released OpenCAL on October 19, 2026, an open-source volumetric 3D printer built around Computed Axial Lithography (CAL), a process that forms an entire part at once inside a rotating vial of resin rather than building it layer by layer. The reference print, a replica of Rodin’s Thinker, formed in 90 seconds.
CAL was invented in Professor Hayden Taylor’s Berkeley lab in 2017 with Lawrence Livermore National Laboratory and published in Science in 2019. It took until now, and a two-year effort by project lead Taylor Waddell with more than 40 contributors, to turn it into a printer someone outside a research lab could actually build.
| Spec | Value |
|---|---|
| Bill of materials | ~$1,638 (June 2026 pricing) |
| Assembly time | 5-6 hours, one person |
| Print time | 1-2 minutes typical |
| Controller | Raspberry Pi 5 + consumer LED projector |
| Resin price | $119.99 per 1 L bottle (Prusa, US) |
A projector fires a changing sequence of light patterns into a spinning resin vial, and the resin cures wherever the accumulated dose crosses a threshold, a process the paper compares to running a CT scan in reverse. There are no layers, no supports, no moving print head. Print prep runs through Tomo, a free Windows app built on the open-source VAMToolbox library.
The resin supply problem that kept CAL in labs is what Formlabs and Prusa solved: Formlabs now manufactures the UDMA-based formula at production scale as OpenCAL Resin, and Prusa sells it through Printed Solid and hosts the printable parts on Printables under its Open Community License (OCL 1.1). Prusa’s Rudolf Krcmar said the company wants “to see OpenCAL printers popping up all over the world.”
Machines are already running or under construction at MIT, Purdue, Lawrence Livermore and NIST. Berkeley will run a build workshop at its VAM27 symposium in February 2027. The source gives no figures for achievable resolution, minimum feature size, or vial/build volume limits.