2025
We expanded our SLS automation cell for the Formlabs Fuse 1+ to include optical cassette and IR sensor cleaning. Using a single robot arm with a tool changer, the cell now performs every step from chamber swapping to precision cleaning.
SLS 3D Printing
Automation
INTRO
Building the foundation for a self-sustaining SLS workflow
Last month we demonstrated how a single robotic arm could manage chamber swaps and powder cleanup for the Formlabs Fuse 1+, creating a compact lights-out SLS cell. That first version automated chamber handling and vacuum cleaning but still relied on human maintenance for two critical tasks: cleaning the optical cassette and the IR sensor.
To remove those manual steps, we equipped the system with new tools and routines that let the robot clean, inspect, and prepare the printer for the next build entirely on its own. With these upgrades, the same cell now performs optical cassette and IR sensor cleaning - two of the most frequent maintenance tasks that previously limited unattended production.
The result is an SLS workflow that runs longer, stays cleaner, and maintains consistent print quality with minimal operator involvement. Read below to see why this step matters and how we built it.
PROBLEM
Why Cleaning Still Limits Automation
SLS printing is ideal for small-batch functional parts, but consistent uptime depends on how well the printer is maintained between jobs.
Even when chamber swaps and powder cleaning are automated, the optical cassette and IR sensor still need regular attention. Powder particles accumulate on the cassette window and around the sensor during each cycle. Over time this affects laser focus and thermal measurement accuracy, which can lead to rejected builds or print interruptions.
Cleaning these components manually requires precision and consistency - two things that are difficult to maintain across shifts. Automating this step ensures every cycle begins with a clean, verified system, preserving print quality and extending hardware lifespan.
WHAT WE DID
Extending the SLS Automation Workflow
The new cell keeps the same foundation: one robotic arm, one printer, and a tool magazine. From there we added several new tools and routines that allow the system to perform complete maintenance automatically.
Optical cassette cleaning
We designed a dedicated nozzle attachment that mounts on a new tool changer. The robot enters the printer bay, sprays ethanol toward the optical cassette, then follows with a pressurized air pass to dry the surface. The cycle runs after every few prints (typically every 5–10 prints or 30 printing hours) to maintain optical clarity without interrupting production.
IR sensor cleaning
The robot checks the sensor after each print. A dedicated jaw gripper removes the sensor and places it on a cleaning stand on top of the printer. The robot then switches to the nozzle attachment to clean and dry the sensor before switching back to the IR sensor gripper and reinstalling it.
Modular gripper jaws exchange
The new IR sensor gripper shares a physical stand with the servo gripper used in the previous automation phase. Instead of adding another tool changer, the robot swaps the jaws of each gripper directly on the stand. The servo gripper continues to handle the printer plug operations - locking and unlocking the build chamber during changeovers, while the IR sensor jaws perform the cleaning cycle.
All other functions remain in place. The vacuum attachment removes powder residue after every print, and the mechanical fork handles chamber loading and unloading. The combined system now executes the full turnover sequence plus cleaning using a single robotic arm. The system maintains a three-chamber buffer to ensure uninterrupted printing and immediate turnaround.
CONCLUSION
Advanced SLS Automation, Ready for Scale
With optical and sensor cleaning now integrated, the Fuse 1+ cell operates at a new level of autonomy. The robot no longer just swaps chambers and clears powder, it also maintains the printer’s key components with precision and consistency. Each cycle runs identically, with chamber changeover, cleaning, and inspection handled by one robotic arm through modular tool changes.
The only remaining manual steps are powder refilling and filter replacement. These require a short operator visit roughly every few prints - about five minutes to top up powder and inspect filters. Filter changes take around ten minutes and occur every one to three days, depending on job volume. In practical terms, the system runs unattended for many hours, needing only brief, scheduled checks to sustain continuous production.
This project shows how incremental automation transforms standard 3D printing equipment into a scalable production platform. The same hardware, the same footprint, but with dramatically higher consistency, reliability, and uptime.
For manufacturers and labs using the Formlabs Fuse series, this upgrade represents a clear step toward truly autonomous SLS production.
Talk to our team to see how DHR can design a custom automation cell that expands your capacity and lowers operational overhead.
If you're facing throughput challenges or planning your next production ramp — let’s talk. We work with hardware teams who build things that matter, and need their automation to move fast and perform flawlessly.