We have built the complete automatic controller for The Liberator Open Source Compressed Earth Brick (CEB) press a year ago, and have demonsttrated up to 16 brick per minute brick pressing rates. Now we move on to technological recursion of the open source CEB controller technology – by circuit milling our own control circuits with an open source CNC Circuit Mill instead of buying them off-the-shelf.
The CEB controller circuit is already open source, as it builds on the RepRap and Arduino projects. It is useful to be able to mill these circuit boards ourselves, in case we can’t get our hands on them, or if we want more flexibility. In this particular case, the desirable flexibility would be combining the 2 solenoid driver boards that we currently use in the controller into 1, for a small improvement in the fabrication of the controller box.
It should be relatively easy to build on existing work to come up with a circuit mill suitable for milling our own circuits. Short of developing a CNC circuit mill ourselves, we have identified these available options. There are many others.
We need your help. First, help us identify the best solution for an open source CNC circuit mill, and then help us source the parts so we can build it (we can’t bootstrap ourselves without another CNC mill or router). We’d like to go straight from self-milled boards, as then we are in full control of the technology and we are forced to understand it at a deeper level. SnapLock, perhaps modified for lower cost, is our best choice now, since we have a collaborator who can help us bootstrap this route. Our RepRap in the making is another possibility, but that seems to be a more complicated route. I personally like the super-strapped $100 option of the Mantis 9 machine – with completely bootstrapped electronics and router spindle – but I don’t like the wood frame.
Second, help us generate the toolpath files that can be used with LinuxCNC to mill our own CEB controller board. This means the 2 solenoid driver boards, on one circuit board. And, while we are at it, it would be useful to mill our clone of Arduino. We can then populate these components.There is some cost savings in this, but the main point is to gain mastery of the technology as producers, not mere consumers.
By the way – grand news. The first ever independent replication of our open source hardware is happening. Someone just built a replica of the CEB press controller from the documentation that we have on the wiki and blog. This is history. This was a totally independent effort, not instigated by me: