Embedded Arch ETHZ CH

Our friends over at the CAAD Chair do stuff we dream about every day...
Canonical hacker Christoph Wartmann is the man to watch - may he inspire us with more of his fantastic ideas and projects...


and make sure to check out his eagle sensor project!

last but no least a few snapshots - there's tons of stuff on his website, a tutorial section, an introduction to arduino, student projects, all sorts of useful links and his master pieces...


Adaptive Systems Lab D-Arch ETHZ

Check out the amazing things our friends (Dino Rossi and his colleagues) over at the Adaptive Systems Lab do with wireless sensor networks and all kind of advanced materials... There's a lot of fabbing going on there!


Concrete Casting Tips

The actual Blog-Statistics indicates strong interest for concrete casting. I assembled some main hints to help you for your own casts. I am not a professional concrete expert, these tips are just condensed info's of my total 5 days of concrete casting.

A Basic Recipe

This is the mixture we used for the models shown in this blog. The mixture has been provided by our concrete specialist Heinz Richner (D-Baug / IfB)

Mixture with Sand 0/1 "Fine"

Material               1 Liter
Cement 52R         982 g 
Flue Ash              165 g
Silika Dust             92 g 
Sand 0/1 *            740 g
Fibers PVA 6mm    16 g
Water                    270 g
Glenium ACE 30   15 g

*For concrete mixture "Normal" use Sand 0/4

Building cast-forms

(In German. Provided by Heinz Richner (D-Baug / IfB))

Schalungsbau Manual

Getting ready

  • Be sure you prepare your project early and gather some experience with this material.
  • Calculate the volume of your project and produce 30-50% more concrete. On one side for covering fails and on the other side to be sure to have enough material.
  • Buy  vaseline, silicone spray, gloves and dust masks
  • Have a recipe ready to calculate your material.


  • When designing your form, think early on how you remove your model when the concrete hardened out.
  • Concrete creates massive forces while hardening. Build your forms accordingly.
  • Stuff floats in fluid concrete. When using foam inserts, remember this.
  • Concrete surfaces reflect the form surface exactly. Use acrylic-glas or polished MDF to get mirror like surfaces. Plastic foils will be deformed because of the forces during hardening. Rough wood-planking result in nice wood structures.
  • Use Vaseline and silicone spray to lubricate your form. Badly lubricated forms are very hard to open after hardening.
  • Review your form. Imagine how you pour concrete in your form, how it distributes, what forces it cause and how you remove the result.


  • Prepare your workspace. How do you transport your finished objects, which form has priority.
  • Prepare your mixture.
  • First dry-mix everything.
  • Slowly, very slowly add 3/4 of your water mixture. Let it stir 1-2 minutes. Then add very small amounts of water while constantly checking the fluidity of your mixture. Never add too much water or add it too fast. The moment, concrete fluidizes happens really fast.
  • Fill your forms and pay attention on how you pour the mixture in your form. If necessary angle your form to release air and be aware of air-traps.
  • Slightly bumping the form on the floor releases bigger air-bubbles.
  • After filling your forms store them in a room with high humidity. Concrete does not dry, it hardens by chemically processing water!
  • Store the forms for a minimum of 24 hours, depending on the mixture you used.


  • When removing your models, be gentle and patient. Never use brute force, you'll damage your model. When getting nervous, better go for a coffee and try again later.
  • To glue model parts together you may use Epoxy or Silicon glue.
  • Handle the model with care, it easily breaks depending on your mixture and thickness.

I hope this helps to get started with concrete casting. Leave a comment if you got success.


Knitted Clothing Simulation

This one is a biggie, clothing simulation at this level has been complicated to do and involved a lot of trickery. This year's SIGGRAPH paper shows the work of a collaboration of Cem Yuksel, Jonathan M. Kaldor, Doug L. James and Steve Marschner. Their paper describes their way to accurately simulate knitted clothing. Fantastic!

 Here some words on the project and some videos, even an implementation in Blender already exists!

Cem Yuksel's Website


3D Printer: The good looking kit....

Junior Veloso posted some more Information on his 3D Printer Kit. It looks nice.

3D Printer: The good looking kit...


Thesis Spring 2012 Part 2

Here some more impressions of our student's diploma work.



Thesis Spring 2012

This year's diploma-models again bear some amazing highlights. These models were produced using our lab equipment like laser-cutters, Zuend cutting-plotter and the wood-workshop. like every year we are pleased what the ETH students accomplish.


Look Mom, We've Got New Laserpower

During semester our laser-tubes are under heavy use for long hours in a row, cutting and engraving tiny pieces. Sooner or later we need to invest in an exchange of laser-tubes.

Here you see the construction of such a tube and a comparison between our old and the new one.



Concrete Casting 2012 Form Removal

After 24 Hours of curing the final forms were removed and the assembly started.

Here some pictures of the assembly few days  before deadline.


CNC-Milled and 3D Printed Master Thesis Model

Lindsay Howe Blair and Vanessa Joos CNC-milled a detailed region of Johannesburg, South-Africa, for their Master Thesis "Post-Apartheid Urbanism". The Model measures about 2m x 1.5m and was milled on our Multicam CNC-mill. Small parts were also 3D-printed on our ZCorp Z650.


Concrete Casting 2012

Every year we give our students the opportunity to cast concrete for their diploma models.

This year we have some really BIG models. We used around 600 Kg of concrete for these models. The Diploma-Show starts this Friday, we blog again next week with photographs of the finished models.


Milled Laser-Queue Waiting Bench

We just made it more comfortable to wait in queue. A CNC-milled bench serves as rest-place to prepare files or just to wait.



To get more consistent labeling of warning messages we decided to renew all labels and use a uniform material. We found nice anodized aluminum plates for this purpose. For the content we did some modelling and composing using Blender and integrated everything to finally laser-engrave the plates.


3D-Printed Torzle

While playing around and testing features of our ZCorp Z650 3D-Printer we encountered a nice website with print-data for creating a "Torzle", a twisted torus made of one single part that is repeatedly stuck into each other to create a pretty cool object.

Apart being a nice Toy or Sculpture speculations also goes into beer brewing (Who thought that!) Here a quote of George Hart's Website:

Beer Yeast Storage Device??

Surprisingly, it seems that this design may be what is known in Danish as a "Gærkrans", which was apparently used to collect and store yeast between beer brews.  Thank you to Bodil G., commenting on a Boing-Boing post of my MakeZine blog, for suggesting this. Here are some references: 1, 2, 3, 4, 5, 6.
After printing it out and some infusion time with super glue we assembled the Torzle, see for yourself :)


Digital-Workshop Laser-Control-System

We reflected how we could improve the management of our 5 Epilog laser-cutters to get a fair and maintenance friendly system. We now can create user-groups, dedicated laser-groups and are able to limit the time per user automatically. Students log-in on our controller-workstation, then the chosen laser-cutter powers on until they log-off.

We built small custom boxes containing an arduino board and a relay to power the machines on and off. The user-interface and database handling has been coded in python.

Using this system we now also provide live usage-information and statistics to help our students planing their laser time.

Here a little photographic production report: