The Liberator – CEB Press Prototype IV – Design Complete

We’re pleased to announce design completion of Prototype IV of the Compressed Earth Brick (CEB) Press.  The machine has come a long way since Prototype I. The main changes since Prototype III – part of our Christmas Gift to the World of 2011 –  includes redesign of the hopper, a stronger frame, the next iteration of the automation controller, and general  streamlining of the design for fabrication.

Below is a video history of the Liberator from 2007 until present :

The CEB Story 2012 from Open Source Ecology on Vimeo.

Below is a video illustrating the latest 3D CAD of the machine.

The improvements are detailed as follows:

  • Hopper Design – The hopper will now catch 99% of the soil dumped into the grate due to reduced hopper aperture and improved cut design of the hopper panels from a single 5×10 sheet of steel.
  • Hopper Interface Saddle – A sheet metal saddle now cradles the hopper and allows a tighter funnel for soil to fall into the compression chamber
  • Compression Chamber – The long sides of the compression chamber can now be cut out of ½” steel with ½” flanges welded on as support contributing to flatter bricks.
  • Primary Structural Improvement – Several structural members of the press are now built out of 3x6x3/8” steel rather than 2×6 “heavy” U-channel improving overall rigidity.
  • Cylinder Press foot – The press foot which presses the bricks is now specified out of abrasion resistant (AR300) steel increasing durability.
  • Press Cylinder – The press cylinder is now specified with a bare shaft on which the press foot is pinned rather than welding in the previous design
  • Hopper Piano Hinge – The hinges holding the walls of the hopper together are now continuous or piano hinges rather than a series of door hinges.
  • Drawer – The drawer is now designed out of nearly all ½” steel plate and could be cut out of a small sheet of it using CNC technology.
  • Drawer supports – The drawer is now supported by 4 cam followers which are held by a modular drawer support assembly.  See image below
  • Grate attachment – The grate is now attached to its structural support using a continuous hinge so the grate can be opened up like a hatch to maintain the soil flow when blockage occurs.

<Click image to Enlarge>

To maximize production efficiency of the Liberator we are using a rapid development platform which utilizes a universal indexing system which includes every raw piece of steel, hydraulic fitting, fastener, and electronic component as well as assemblies of components.  This index is a base to reference from every other piece of documentation.  I have also created a diagram which graphically indicates the sequence of composition of these components and assemblies.

The Liberator IV CAD files in Solidworks 2012 format and .step format are on the wiki.  You can also download a complete set of fabrication drawings. The Bill of Materials is on the wiki. The latest on the electronics are  Solenoid Driver, Terminal Case, PCB Mount and Terminal Block. The current hydraulics design is compiled in a schematic diagram.

We began our first Collaborative Production run today, and some of the above fabrication files are already being modified, so proceed at your own risk if you want to replicate. We will update the CAD and fab drawings as soon as we are able.




  1. Full Product Release | Factor E Farm Blog

    […] Note: this is not a Full Product Release as stated. Further prototypes and improvements have been made, see update post of Sep. 24, 2012.  […]

  2. anon

    These new videos are really cool, well done to the who ever made them 🙂

  3. john

    Congratulations! This is really really exciting!

  4. Rich Fitzner

    I am the lead mentor of a high school FIRST robotics team. Our robotics competition season runs from Jan. – March. What are your thoughts of our team of 14 – 17 year old students capability to construct the liberator over the other five months of the school year? We have a large work area with a drill press, band saws, a tig welder, and electrical wiring ability. I would like to be able to possibly donate it to worthy organization/entity when complete.

    1. marcin jakubowski

      This is definitely possible. Please email me at marcin at opensourceecology dot org to discuss details.

  5. […] Diagram, and sourced the materials for the production run. You can download all the files from our last blog post on the CEB. The social results were positive, while production efficiencies need […]

  6. Alan Pierce

    You guys are doing an amazing job and are truly an inspiration to everybody who sees your efforts and understands the magnitude of your goals. I hope one day to be able come and either aid in some way or be an independant replicator. Keep going!!!

    Alan Pierce

  7. Tom Braak

    Would love to have a liberator for our work in Haiti. We could use it to build our compound and later many schools. We could also sell the brick. Everyone likes concrete block but most could never afford one. This is the perfect solution. I may try to find someone to build one for us.

  8. Marcin

    September 24-28 was our first Collaborative Production Run for the CEB Press. The next is Nov. 23-24 – to get production time down to 2 days, and grand finale is no Dec. 18 as we aim to get production down to 1 day.

  9. […] have streamlined the production of our open source, automated, compressed earth brick (CEB) press, The Liberator – down to a single day of production – via small-scale, open source, Collaborative Production. […]