Could a Pug Mill be used to make uniform Earth Bricks suitable for construction?

I've been looking for ways to create Compressed Earth Bricks and thought about using a Pug Mill (commonly used to get air out of clay) with a rectangular extruder to do all the hard work.  Has anyone had experience with these mills?  Am I crazy for thinking this could speed up the process of building with earth?

Comments

[steveastrouk]

I don't see how you would get the isostatic compression that making them individually would give you, so the resulting blocks would tend to fall apart.

Steve

[kretzlord]

I'm just going by my limited experience with pug mills. The extrusion that comes out of them is pretty darn solid (and yes, i understand a mix using sand would be less so). as far as the compression goes, i know these mills are used to remove all air from clay, giving the highest possible density with a given material.

If you could have an extrusion of say, 10'x8"x18", you could cut it into sections and let the blocks dry individually. This would turn the blocks into a batch process rather than a 1-off.

Thanks for the replies!

[steveastrouk]

Don't get me wrong, I like the idea too, but I just have doubts that the resulting block could ever be as dense as a simple pressed block, and I know that earth block strength COMES from that compression.

I'd be "happier" (as if my view mattered.... :-) ) if you extruded your block and THEN stuck it into a form to apply a substantial squish (technical term) to set a final, high compression.

I think you'd still be winning, in terms of labour saved.

[Kiteman]

What is the normal method for making earth bricks?

Most earth-built houses I have seen recently have the earth in bags, or poured into hollow forms that stay in place when the house is built.

[kretzlord]

well, i had my terminology wrong, they are "Compressed Earth Blocks". the method involves having a slightly damp clay/sand/binder mixture that gets pressed in a form. the blocks are released from the form and set out to dry The blocks are made one at a time this way, though there are larger machines that automate the process. the result is similar to a rammed earth wall (but much smaller)

http://en.wikipedia.org/wiki/Compressed_earth_block