After seeing a question about FDM printing of temperature-resistant parts, high-temperature 2-part epoxy came to mind. Are there any (experimental or production) FDM extruders for laying viscous, fast-curing epoxy, mixing it at the last moment before extrusion? Or likewise other cured/resin materials, either 2-part or UV-cured (with whole print volume flooded with UV)?
Yes, it has been done for many years - but it's not referred to as FDM when you use deposition of resins. At room temperature it's often called Direct Ink Writing (DIW, example), and if heated it's often called Hot Melt Extrusion (HME, example).
Disclaimer: I work for Hyrel 3D, a 3D printer manufacturer which has been making heads that deposit one- or two-part resins since 2015. See over 300 published papers, many of which cite this exact process.
Apparently now the answer is yes. A company called MASSIVit has a system they call GDP - gel dispensing printing - that's essentially what I asked about, on an extremely large scale. 3D Printing Nerd has a video from their booth at Formnext 2021 in Frankfurt, Germany.
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Material blasting is a unique 3D resin printing technology that can be compared to an office inkjet printer. It is also considered one of the fastest and most accurate 3D printing technologies available for resin printing today.
Material Beam 3D printers are similar to inkjet 3D printers in that they also have a print head from which thousands of tiny resin droplets are applied to the building platform and then cured with UV light. Once a layer has been completed, the building platform automatically lowers to the height of a layer and the process is repeated until the object is completed.
The technology of material blasting enables high dimensional accuracy, but speed is also a convincing point. The process in which the resin droplets are ejected from several print heads, which in turn move back and forth over the building platform, is known as line-by-line cutting. This ensures that multiple parts can be produced without affecting the build speed. As a user, you also have the choice between matte and shiny surfaces on your 3D printed object. However, the individual components for material beam technology are very cost-intensive. Other disadvantages are the waste of material when you choose to print matt surfaces and the low strength of the 3D printed parts.
There is this enter link description here printer which uses a liquid resin that's cured using UV at the very tip of the nozel, it prints in layers like an FDM printer and is extremely fast but can't do small details.
I've only ever seen it print at a large scale I don't know if there is a prototype for a desktop version.