Jack Moldave

Formlabs is a 3d printing company that specializes in making desktop stereolithography printers. They are best known for the Form 1, Form 2, and Form 3 and are one of the leaders in the 3d printing world. 

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During my time at Formlabs, I had the privilege of working on many different aspects of 3D printing in many different roles and capacities. I started out on the Print Process team, an interdisciplinary team focused on developing features and processes to make the Form 2 print as efficiently and beautifully as possible. When I started on the Print Process Team, the Form 2 was just launching and the first printers were being delivered to customers. Therefore, I was able to jump right in and start debugging print process artifacts immediately. While on the process team, I worked on all areas of the print process, from laser path planning, to redesigning support structures to reduce markings on parts, to managing multiple R&D projects for next generation technologies.

The Form 3

About 6 months months into my tenure at Formlabs, Form 3 began. This would be end up being some of the most exciting and my favorite times at Formlabs. So I transitioned from feature development from the Form 2 to R&D for the next generation printer. This involved testing any and every idea that we could think of to improve the print process as quickly as possible. I remember some days we thought of an idea in the morning, built a prototype in the afternoon and had a successfully printed test print that very same night. During this time I managed several different R&D projects, including the project that ended up becoming the core technology for the Form 3.

After the technology for the Form 3 was chosen, I was promoted to the Mechanical Engineering Design Team to design the Form 3 for mass production. This was very exciting, as it was the first time I was given the opportunity to see a product through from conception to mass production. While I was primarily a mechanical design engineer for several electromechanical subsystems I also ended up being thrown into several project management roles to ensure that many subsystems in the printer were developed on time and up to spec. My time on the print process team dramatically helped me function efficiently in this role, since I was able to be hands on with EE, Process Engineers, Software Engineers, and do any mechanical design work myself.

Eventually, after much blood sweat and tears, the final prototype of the printer was finished and validated, and we moved forward to mass production. This involved constant communication with our overseas vendors and making all those small optimizations to parts for DFM and overall reliability, as well as demanding test plans to ensure that all parts and systems functioned properly at quantity. I even took my first trip to China to inspect my T0 IM parts and oversea operations at our factories. And then in April, we were given the go ahead and the printer was announced to the public! Now that things are public, I have included a small selection of projects to share.

 

Formlabs Project Gallery

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Form 3 Mixer Project

 

The Form 3 mixer is an essential electromechanical subsystem on the Form 3. The mixer’s prime function, as its name implies, is to mix the resin before a print to ensure consistent quality and process over thousands of prints. Beyond that though, the mixer in the Form 3 is designed to do so much more. There is a front scraping blade that will remove failures from the film to avoid print failures and unwanted artifacts. There is another re-coating blade on the back that ensures there is an even coat of resin that follows every mixer “wipe.” And there is even a third blade on the top that will be used to detect objects on the build platform. This ensures that there are no sharp shards of hardened resin from previous prints on the build platform that could run the risk of puncturing the film.  

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            The mixer is actuated through a magnetic coupling that actually goes through the film in the tank. This reduces user interaction with the mixer and makes coupling automatic, whereas a Form 2 user would have manually had to connect the wiper every time a tank was changed. Furthermore, with a magnetic coupling, the system is able to detect when the mixer disengages with a hall effect sensor. This not only allows the system to detect errors, but potentially self correct and eliminate a failed print. If the mixer encounters a large enough failure on the film, it will actually decouple from the magnetic coupling, the hall effect sensors will pick this up, and the printer will alert the user that there is debris in the tank. Finally you will notice that the mixer has two flexures on either side. These are the “parking features” that keep the mixer in places while the printer is running a print. This prevents the mixer from disturbing the print process and ensures that it is always in a safe location.

 

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Form 3 Level Sense

 

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The Level Sense system in the Form 3 is responsible for ensuring that a print never runs out of resin, and that there is never too much resin in the system that could cause an overflow. This is another quintessential electromechanical system that is necessary for printing for a variety of reasons. Leveraging experience from the development of Form 2 Level Sense, there were new requirements and metrics that Form 3 Level Sense needed to hit. There needed to be the ability to continuously sense the resins level, in order to speed up print times and avoid artifacts resulting from pauses during the printer. Form 3 Level Sense also needed to be future proofed for all materials that would be developed during the printer’s life time.

To accomplish this, a mechanical float is used together with a target which facilitates non-contact sensing through the tank to the printer. The float component moves up and down in response to the resin height, and the target in the back of it moves accordingly. There is a sensor on the printer that picks up the movement in this target, and then is able to calculate the height of the resin. All this is able to be done continuously at any point in the print, and allows the printer to make parts nonstop, without any pauses for sensing the resin level.