Model of the Month – May
Congratulations to Carlo Quinonez, the Model of the Month winner for May! He has created an extremely unique thermal chamber for his work at FATHOM, aiming to enable community-driven development of the tools scientists use in the lab. Read below about how he came up with this idea and where he can see it going in the future.
I’m Carlo Quinonez, currently the Director of Research at FATHOM, an additive manufacturing-focused company driven by advanced technologies that enhance its customers’ product development process. I have over twenty years of experience in additive manufacturing, prototyping, product design, and electrical and mechanical engineering. Although I received a doctorate in biology from the California Institute of Technology, I’m really an engineer at heart—I just didn’t realize that until halfway through grad school! After obtaining my PhD, I focused on hardware development and joined a product design studio building bespoke lighting systems. However, my passion has always been developing tools for scientists, and my path eventually led me back to science as a post-doctoral researcher at the University of California, San Diego. There, I developed 3D-printable scientific instrumentation for microfluidic experiments, including the earliest versions of this thermal chamber. After my post-doc, I joined Autodesk Research and worked on cloud-based design tools for life sciences. As Director of Research at FATHOM, I coordinate internal and external research projects at the forefront of advanced manufacturing.
Thermal Chamber Project
In 2009, I started my post-doc at UCSD with the goal of reviving a hand-built instrument that was used in some older research. The instrument was built by a graduate student as part of his thesis and could do some remarkable things. However, I struggled to figure out how to reassemble everything and get it working, so I decided to start from scratch and focus on using 3D printing wherever possible so it would be easier for other scientists to reproduce. The central piece of hardware was an incubator: a chamber used to maintain a constant environment (including temperature) to keep cells alive.
The first version looked a lot like other commercially available incubators designed to sit on top of a microscope. I used heaters attached to a large aluminum chamber to evenly warm the incubator, but the rest of the parts were 3D-printed plastic.
Over time, I realized that making it look like other incubators was making the CAD hard to handle. I asked myself, “Why am I designing a box when I have a 3D printer?” The answer, of course, was that’s the way all incubators look! Challenging that assumption led to some changes in the next version—I removed the hard edges and started letting the underlying function dictate the form.
Over the 3 years of my post-doc, the design for the incubator continued to evolve, and I began to incorporate more and more functionality into the 3D-printed portions of the incubator. However, I never questioned the central assumption that I needed to use a metal chamber to maintain a constant temperature. Incubators traditionally use metal because of the high thermal conductivity inherent to metal. Plastic is basically an insulator, and you can’t stick a heater on a sheet of plastic and expect it to work the same, if at all.
When I finished my post-doc and worked on other projects, the thought of making a completely 3D-printable incubator gnawed at me for years. Recently, while exploring other complex 3D-printable geometries, my thoughts turned back to the incubator I’d made at UCSD. Could I use complex geometry to work around the inherent limitations of plastic and make a thermal chamber?
I started exploring this question while I was an Artist-in-Residence at Autodesk’s Pier 9 at the end of 2014. I used the opportunity to explore how to design printable geometries for forced air convective heating. In the image above, you can get a sense of the ducting and heat exchangers that are integrated into the design of the red component. This is just a proof-of-concept model so that I could get a feel for the geometries before trying to build a full chamber.
The residency was over a lot quicker than I realized, so I didn’t get as much done as I’d liked. But I did get to spend a few weeks working with Autodesk’s Ember printer to print out all of the early proof-of-concept models. After my residency ended, I started working on a full size version on nights and weekends. Over the next few months leading up to the Bay Area MakerFaire this year, I finished all the designs for a full-size prototype.
The design for the 3D-printable thermal chamber uses forced air convection through a series of ducts to evenly heat the chamber walls. The CAD for the prototype is the most complicated design I’ve ever made—re-computing the feature tree takes almost an hour on my workstation! With this design, I let the form emerge from the underlying functionality. It’s a pyramid because I’m designing it to be printable on an FDM printer, like a Makerbot, and sloping sides of 45 degrees are self-supporting. A 3D-printed fan in the base circulates air over heating elements and through the ductwork. The electronics are based on a Raspberry Pi to monitor the temperature and control the heater and fan accordingly.
We’re currently printing out a full-size chamber at FATHOM and will be testing it shortly!
My big vision with this project is to enable community-driven development of the tools scientists use in the lab. I’ll be making the thermal chamber designs open-source so anyone can download, customize, and print their own versions. Of course, a key part of that is having access to professional CAD tools that can handle the complex geometries we need to use. Since Fusion is freely available to hobbyists and anyone in education, it seemed like a great choice. The added ability to easily share and collaborate on CAD designs and is perfect for an open-source project like this. I love using Fusion and really appreciate the cloud rendering feature that simplifies the creation of stunning renderings like the visuals I’ve shared on the project gallery. I’m also planning on using the programming API’s to automate aspects of the design to make it easier for others to design their own chambers without laboring through all the hard work themselves.