Autodesk Aims to Replicate Speed & Precision of Gizmo 3D’s Ultra-Fast 3D Printing
Carbon3D created quite a stir when they announced their super fast CLIP technologythat grows parts instead of building them layer by layer. The announcement spawneda race to match the top-down, high-speed (100 mm/hr – 500 mm/hr) DLP-SLA technology, including an Australian company called Gizmo 3D, which hopes to launch its own similar technology this year. With the race for speed gearing up all over the world, Andreas Bastian, a 3D printing research scientist at Autodesk, wanted to see what all the fuss was about regarding the top-down DLP process used by Gizmo 3D. The Autodesk Ember team, led by Bastian, set out to build their own top-down printer that stood up to the high-speed hype, presenting their findings as an Instructable.
The Ember team was more interested in learning about top-down DLP and the strengths and weaknesses of the process and decided to investigate Gizmo 3D’s claims, as they seemed to offer a significant differentiating factor between bottom-up and top-down. Gizmo 3D’s research and development was done in secret and, so, Bastian and his team wanted to put in the hours to try to match their results and see what happened.
Bastian explains in the Instructable, “Given the magnitude of some of these claims–up to 500 millimeters per hour–if true, it would appear that others had made substantial advances in the stereolithography process that would be worthy of investigation. The Ember team was curious about these claims, so we built a top down DLP SLA 3D printer, with Fusion 360 and STEP files attached, and attempted to reproduce the results…”
Here is Bastian’s list of the parameters, employed by the team:
- Continuous build speeds of between 100mm/hr and 500mm/hr
- Discrete, layered build speeds of between 100mm/hr and 350mm/hr
- Continuous exposures
- Discrete, shuttered exposures
- Liquid-liquid incident light interfaces
- Sonication of the resin
- Oscillatory resin vibration
- Dipping cycles
- Inclined build platforms
- Mesh build platforms
Team member Cappie Pomeroy worked with the team to design programming for the project. Together, they automated the hardware and began to test several different kinds of resin including the following:
- PR48 – the standard Autodesk resin for prototypes, with viscosity of 183 mPa·s
- Spot A Materials’ Spot-GP Resin– 63 mPa·s
- Fun To Do Industrial Blend Red Resin– the team was not able to measure the viscosity, but estimates it to be close to PR48 and Spot-GP
- Homemade low viscosity resin – Created by Ember team polymer chemist Brian Adzima. Estimated viscosity was 60 mPa·s, similar to the others.
From those resins, a variety of geometries with thin walls from 0.5mm and 3.0mm, as well as an array of tubes and a skull model with a 2 mm shell, were all printed as tests. Their results showed promise; they were able to build their own top-down printer. The Ember team was a big asset, as it used the Ember’s Z-stage for bringing down the build platform into the resin pool 100um at a time. They were even able to match some of the claims of speed in 3D printing a skull geometry. Bastian said, “We were able to build a somewhat solid geometry at a build rate of approximately 120 to 150 millimeters per hour.” But, they also experienced a lot of problems with the top-down DLP process as they kept on printing.
Bastian reported their findings, saying, “While we were able to replicate speeds close to those claimed in the Gizmo3D video, we were unable to do so with any meaningful object coherence or build quality. We were, however, able to gain a better understanding of the problem-space for top-down DLP SLA in its continuous and discrete implementations.”
The real win from Autodesk and Ember’s experimenting is that they have developed a list of solutions, concerns, and items to continue investigating in regards to the DLP SLA printer. They found that, gaining speed, the printer lost any type of assured quality. The ‘dead zone’, or areas where curing is not allowed, makes it so that it is impossible to manipulate the resin the way Gizmo 3D seems to be able to do with their technology. The team explained, “The top surface immediately cures, the sidewalls begin to form again, and the process repeats. This results in weakly connected ‘layers’ and an overall very porous object.”
Lateral migration and viscous flow of cured material proved to be an issue. The cured material expanded and began to sink, spreading and “[scrolling] up.” This caused obvious surface tension problems and a disrupted workflow. But, Bastian and his team didn’t just note the problems with this technology, they also came up with several solutions for improvement.