Shelter 2.0 is a flat-packed plywood structure that anyone can build with the assistance of a CNC router. For years my longtime Shelter 2.0 collaborator Robert Bridges and I have been shipping Shelter kits all over the world. The Shelter 2.0 project began life as Robert’s entry in a contest hosted by the Guggenheim Museum and SketchUp. Inspired by the iconic Quonset hut, it incorporated a barreled ceiling that we had worked on as we admired the strength and aesthetic appeal of those sorts of curved shapes … a ShopBot can cut a curve as easily as a straight line.

Although originally conceived as transitional housing in emergency situations, the Shelter 2.0 design has been used as housing for the homeless, as team-building projects in schools, and is in the planning stages to provide an option for refugee housing through the Global Humanitarian Lab. It was designed for efficient CNC cutting; we make the CNC files available online so that anyone can cut them, but it requires a CNC machine. We can easily cut and ship them anywhere in the world, or we can ship CNC machines so that Shelters can be cut on site.

Unfortunately both of these options have some problems. Setting up a shop can be expensive, and then teaching someone to run the equipment on short notice is problematic at best, especially when a disaster hits. Cutting and shipping structures is slow and costly, or requires stockpiling, which ties up money.

Shelter 2.0 built from construction lumber

Digital Meets Analog

The Shelter 2.0 design requires multiple copies of a small number of pieces. The trick is to duplicate those copies accurately without having to CNC cut every one of them. That’s exactly how it worked when things were strictly analog. CNC cutting the original patterns would give us the accuracy that we struggled with when hand-making templates. Once these patterns are created, anyone can duplicate them with easily available hand power tools. A hand router with a flush trim bit works well for cutting out pieces, but a plunge router with properly sized templates and a guide bushing also makes it easy to cut holes and mill features that don’t go all the way through.

Over the years Robert and I have worked on quite a few innovative CNC-fabricated house prototypes, and in spite of how careful we and the designers had been, once we started to assemble the structure we would often find at least one missing slot or even a whole part that required on-site fabrication. We’ve never had a CNC machine with us but always seem to have a hand router, and have successfully used this duplication technique to copy a whole part on the job using an existing part as the template, or just add a missing slot, dogbone, or some other feature.

Shelter 2.0 in Haiti

Packed with Potential

Not every technique works for all cases and this one is no different. There are lots of amazing projects and designs that are only possible using digital fabrication tools from start to finish, but there are others where using a similar combination of digital and analog techniques makes a lot of sense. Although we originally became interested in this technique for fabricating Shelter 2.0 in sub-optimal conditions, we’re exploring fabricating all sorts of products where a CNC machine might not be available.

I’m still incredibly passionate about the potential that digital fabrication, especially CNC routing, has for revolutionizing the way that much of the things in our lives are made. If you already have access to a CNC machine, put it to work! But if not maybe this digital/analog hybrid system is worth a look.

This works best when:

»There’s a limited number of unique parts in a design, but several copies of each are needed.

»The parts require mostly 2D outline cutting (although some 3D features like pockets are certainly possible).

»There is an excess of available labor. The process can branch and grow as extra labor becomes available.

»There’s poor security or electrical infrastructure. All the tools needed for this system are small, can be powered by a small generator or solar panels, and can be locked in a closet or secure toolbox.

»The design is somewhat “material agnostic,” allowing the use of a wide range of materials.

»You don’t need absolute precision, or don’t mind a couple of screw holes on your parts.

What are the benefits on a large scale?

This works really well occasionally for duplicating a single missing part or feature, but does it make sense as a manufacturing technique? Here’s why we think it does:

» The files are digital, so patterns can be CNC cut locally, or shipped from elsewhere. A set of patterns is a much smaller package to transport, and only
needs to be done once.

» Most of the knowledge and all of the precision is built into the CNC-cut pattern. Techniques for duplicating the patterns with traditional hand power tools (drills, jigsaws, and hand-held routers) can be learned quickly.

» It can expand. You can increase the number of parts you can produce by simply duplicating the templates on-site and adding more people and hand tools.

» It’s easy to “backup.” A copy of the template can be created and used as the working set, saving the original.

» It can work with materials that are hard to CNC cut.