We are glad to report that the LifeTrac-mounted, open source soil pulverizer has annihilated soil-handling limits from our compressed earth brick (CEB) pressing ability. Initial testing achieved 5 ton per hour soil throughput, while The Liberator CEB press requires about 2 tons of soil per hour.
We have shown the pulverizer rotor development in a previous post. See the build and testing of the machine after the addition of the bucket and lift cylinder:
The tractor-mounted pulverizer is used to dig soil and load it directly into the CEB machine. Other CEB pressing industry standards may involve a tractor loader, stationary soil pulverizer, conveyor, and then the CEB machine. See this example from Powell and Sons. We’re replacing the stationary soil pulverizer and conveyor with LifeTrac. This simplifies the equipment costs significantly – and our initial tests show that our strategy works well.
Stationary soil pulverizers comparable in throughput to ours cost over $20k. Ours cost $200 in materials – which is not bad in terms of 100-fold price reduction. The trick to this feat is modular design. We are using components that are already part of our LifeTrac infrastructure. The hydraulic motor is our power take-off (PTO) motor, the rotor is the same tiller that we made last year – with the tiller tines replaced by pulverizer tines. The bucket is the same standard loader bucket that we use for many other applications.
Yes, we are making the dream of a life-size lego set for heavy equipment a reality. This has huge economic significance, and is noteworthy from the post-scarcity perspecive.
It is interesting to compare this development to our CEB work from last year – given our lesson that soil moving is the main bottleneck in earth building. It takes 16 people, 2 walk-behind rototillers, many shovels and buckets, plus backbreaking labor – to load our machine as fast as it can produce bricks. We can now replace this number of people with 1 person – by mechanizing the earth moving work with the tractor-mounted pulverizer. In a sample run, it took us about 2 minutes to load the pulverizer bucket – with soil sufficient for about 30 bricks. Our machine produces 5 bricks per minute – so we have succeeded in removing the soil-loading bottleneck from the equation.
This is a major milestone for our ability to do CEB construction. Our results indicate that we can press 2500 bricks in an 8 hour day – with 3 people. One person is the tractor operator, the second person runs the controls, and the third person stacks bricks on pallets. Further optimization involves adding automatic controls to the CEB machine, so the same task can be accomplished with 2 people.
We haven’t seen a similar combination loader-pulverizer anywhere else. Have you? Our strategy appears to be the most efficient from the ergonomic perspective.
Completion of our CEB building infrastructure – a critical component of the Global Village Construction Set – is forthcoming. This includes the large CEB hopper, multipurpose slurry mixer for mortar, and mud sprayer for plastering. This will finally allow us to build effectively – and to bootstrap ourselves out of an inadequate built environment.