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

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?


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.


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!

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.

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.

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)