Make Architecture



Final Project: Breathing Wall


The goal of this project was to create a building system using the tools and techniques learned over the course of the term while solving a problem. I chose to tackle the problem of transferring motion through a modular system such that each unit could use the motion to affect some change. I created a modular aggregating wall system with a gear train embedded in the wall. Merely by placing more wall “bricks” next to or on top of an existing one extends the gear train into the new brick, so the system is infinitely aggregatable with only friction and construction imprecisions limiting the scale. I then used this embedded gear train to act on the wall surface, pulling apart and bringing back together the stretched fabric skin for a breathing effect.

Over the course of this post, I will describe some of the work, and split how to make this system into three parts – the basic wall brick, a motor brick to power the wall, and how to make this specific surface system.


I looked at previous aggregating systems as well as systems that involve motion as the precedents for this project. Some of these precedents include

Heather Roberge’s tiling systems, although static, show how modules can aggregate together to create unique wall surfaces

Maison De Verre, where many of the building elements involve motion also inspired a motion-based architectural system

Ralph Steiner’s work with gears also inspired the work and showed a lot of what was possible with gearing  systems

Living Glass by Soo-in Yang and David Benjamin, for its opening and closing surface

Finally another inspiration for the apertures (and the color) was BMW’s Gina concept car

In terms of my previous work – my best projects came from the shop bot, which led me to use that as my primary machine. I had become better acquainted with its features from these two projects and had no problems at all running the machine because of it

Rotating Pocket milled piece:

And the week on gears also helped me such that constructing the gears for this project was a manageable task


Now I will show you the procedure for building the pieces of the breathing wall project

Basic Wall Unit


For each 1 foot by 2 foot wall unit, I used:

Roughly 12 square feet of 1/2″ plywood

24″ of 1/4″ threaded rod with 10 Nylon Spacers, 10 fender washers and lock washers, and 20 nuts

Thread Locker Fluid

Tools you will need:

Shop Bot CNC mill

Band Saw to cut threaded rod

Hand Tools, specifically Wrenches and a Mallet, and a file for cleaning up edges


For the design, I started planning in 2d, then designed in 3d, then went back to 2d for laying out pieces and editing details. I did all these steps in Rhino, then saved as .dxf for cutting on the shop bot. The first step is to lay out the gear pitch wheels in plan such that you get the desired ratios and that the brick is aggregatable. Don’t forget the thickness of the walls. An easy way to make sure the pitch circles are tangent is to use the quad snap point when creating the circles, then only rotating them around the center of the adjacent circle.  I started with the assumption that my unit would be 1′ x 2′, that I wanted to main gears running at a 1:2 ratio, and I wanted a connection point at the sides and top. The next step is to run the GearGen script (described in Varvara’s Page) to make all the gear profiles. In order to make the gears with the largest profiles possible, for robustness and so that the mill bit could make all the details, I made the smallest gear have 13 teeth, then based all the other gears on having all the same module. This means that there will be no stepping down or up of gear power through the train.

The next step is to bring it into 3d, giving the gears thickness, designing the supports that their axles will sit on, and designing the 4 outer walls with appropriate openings such that the gears can travel through to connect to the ones next to them. Also make sure to put in tabs for friction fit assembly.

Finally bring it back into 2d using the make2d command on each part. Then do some test cuts on your specific material to determine what offsets work best for friction fit pieces and the gears. In order to have a good fit, I reduced each tab’s width by .05″ and the thickness of slots to .42″. I also offset the gears by 1/32 so they are less likely to get stuck, and decreased the hole size for the spacers to .495″ from .5″ so they fit very snugly. Then lay out the pieces efficiently for the shop bot, remembering that you need about 1″ in between pieces to avoid excessive vibration. I had Home Depot cut my plywood into 2′ x 4′ pieces so I could easily transport them, so I needed 1 and 1/3 sheets per brick – so I cut 3 of the top sheet for every 1 of the bottom sheet.


I then ran these on the shop bot with a 1/4″ mill. For details on how to do this on the Media Lab’s shop bot, which is what I used, see Juliet’s excellent Guru post on the Shop Bot. I bought 2 4’x8′ sheets of plywood at home depot, giving me enough wood to make 5 of these units with left over wood for the motor unit and the wood I used for testing. Each sheet takes about 15 minutes to cut, but with prep time it grew to about 25 minutes per sheet. Make sure to leave enough time to cut everything! It is very important to screw down the sheet to the bed everywhere you can to avoid vibrations which lead to inaccuracies – its worth the time to put in a lot of screws.

One problem I ran into is that some of the plywood delaminated, making the pieces splay apart. I just glued them back together using wood glue

The other part of fabrication is to cut the threaded rod down to size – I had 3 rods at 4″ each and 2 rods at 5″ for each brick. The trick is to put a nut on each side of a cut to keep the rod up and so that you can repair the threads by twisting them off if the cut messes something up.


This is the fun part! Take all of your pieces:

First hammer in the nylon spacers to the support pieces

note: halfway through I ran out of nylon spacers, and I could not find more anywhere. Solution: make some more on the laser cutter. Almost exactly the same.

Then you should put together the gear and axle assemblies, which includes a fender washer, lock washer, and nut on each side. The axle should only stick out one nut’s thickness on the front side of the support piece, (about 1″ for the two main gears) so use one of the side pieces as a guide for placement on the threaded rod.

The easiest procedure from here is to secure the axles into their holes on the front support, then hammer in the bottom, sides, and top. Finally line up the axles and hammer on the back support. Excessive force and possibly filing will be necessary if you offset it right for a friction fit. Make sure the gears line up in their holes, you can hammer for hours to no avail if the gear is stuck.

At this point, you should put a nut on the other side of each axle, adjust the nuts so that all the gears line up best and there is the least friction with the side holes, then use thread locker on the outside nuts so they don’t slide. I made the mistake of trying to weld the nuts in place for one of the bricks, which melted the nylon spacer leaving the brick with such high friction in turning that it is essentially useless. One casualty for 5 bricks isn’t a bad record though.

And thats it! repeat for as many bricks as you have and you can put them next to each other to transmit the motion.

Power Brick


For the 1 foot by 1 foot power brick I used:

Roughly 4 square feet of 1/2″ plywood

12″ of 1/4″ threaded rod with 6 Nylon Spacers, 6 fender washers and lock washers, and 10 nuts

Thread Locker Fluid

One motor, preferably high torque to overcome the friction in the wood

1 square foot of plexi

Tools you will need:

Shop Bot CNC mill

Band Saw to cut threaded rod

Laser cutter to cut acrylic

Hand Tools, specifically Wrenches and a Mallet, and a file for cleaning up edges

Soldering Iron


For the design of the power brick, I started with the existing wall brick in 3d so that I could have the one gear that would connect it with the rest of the train. I cut the size in half, so I rescaled the top and bottom pieces and the support pieces. I wanted to step down my motor from about 24 rpm to about 1 rpm, so I designed in 3 gear size changes using the same gear layout technique as above. Because the teeth get smaller, I needed to use a laser cutter instead of the cnc for the small drills. This motor came with an IGES file of its shape, so it was easy to design the slot for it in the support piece and the d-shaped hole in the connecting gear. Below are the 3d model and layouts for the motor brick for the CNC and the Laser.

Fabrication and Assembly

Fabrication and essentially are almost exactly the same as for the wall brick. Laser cutting the smaller gears means you need a smaller offset because the laser is more precise. Also, remember the motor needs to fit snugly in its hole, I over filed the hole and it wiggled a bit, so I used a rubber band to hold it in place. I soldered the power cable on, and then ran it through the back

All you need to do is set it next to a wall brick, plug it in, and go!

Wall Surface


For each 1 foot by 2 foot wall unit, I used:

roughly 15″ x 30″ of stretch knit fabric (I chose gray so it wouldn’t show the grime of the shop, but any color works)

4 fender washers and nuts, 2 end nuts

Acrylic (about 1 square foot)

A 1/4″ dowel (at least 2 feet)

Tools you will need:

Laser Cutter

Fabric Scissors

Staple Gun

Hand Tools, specifically Wrenches and a Mallet, and a file for cleaning up edges


Not much computer designing went into this part, but after a few iterations of how to interact with the fabric surface, I chose the pulling apart design, which simply uses the pegged arms to create apertures in the fabric.

Here is the layout for one set of arms to cut on the laser cutter


I cut the arms from acrylic on the laser cutter, reducing the holes for the dowels to .225″ for a snug fit. Then I cut the dowel into 1.5″ lengths for the big arm and 1.25″ lengths for the small arm, then just hammered them in

Then I cut the fabric into pieces to stretch over the front. 15″ tall, 8″ wide for the outsides, then 12″ wide for the center piece.


To begin, I attached the arms to the end of the 2 main wheels’ axles. I wanted the front of the arm to line up with the front of the box, so some creativity was necessary because each of the axles was a slightly different length.

Now comes time to stretch the fabric. I typically stapled each side first, then the middle, stapling the top, then bottom, then folding over and stapling the sides. Trial and error was necessary with the stretchyness of the fabric to get the right tightness.

One down, 4 more to go!

Last Staple!



Breathing Wall in Motion

The quality is poor (taken from my phone) and there is a mill running in the background so it is a loud environment.


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Instructor: Nick Gelpi TA: Skylar Tibbits TA: Varvara Toulkeridou
Class Times, Monday, 1-4pm - room 5-216
4.184 is an intensive introduction to methods of making explored through a wide range of brief but focused 1-week exercises. We'll engage the real and leave behind representation in the focused context of this class gaining skills for utilizing a range of fabrication machines and technologies from lasercutting, waterjet, 3D printing, welding, formworking-molding, casting, gears, joints and composites.
In this workshop we'll constrain ourselves to the territory of the 1:1. Students will represent architectural constructions at full scale and develop a more intimate relationship with technology by engaging the tools and techniques that empower us. We will gain access to the most cutting edge machines and technologies in the MARS lab at the Center for Bits and Atoms.
The second layer of information for this course will be to look at a series of case studies in which construction methods and technologies have played a dominant role in the design process .
Over the past 20 years, architects have focused on the technology of representation to create new ideas of what architecture could be. Looking back today, much of that research failed to substantially change the way we design buildings by focusing on apriori formal configurations. This class makes the contention that this failure comes from a lack of considerations of the potentials within fabrication knowledge. We look to the future of what building might become, given the expanded palette of personalize-able technologies available to us as architects. Students will participate in curious technological and material investigations, to discover the potentials, known and unknown, for these various technologies.
The sub-disciplines of what's drawn and what's built have been compartmentalized and disassociated as the representational tools of architecture have distanced themselves from the techniques of making. At the same time the technologies for “making” in architecture have provided us with new possibilities for reinventing how we translate into reality, the immaterial representations of architecture.


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