I want to try out a few small projects around the homestead using rammed earth methods, before embarking on bigger things.
Will a small jackhammer like the one in the picture be able to compact the earth enough if I weld on a small foot or something on the end?
Wait, are you wanting to build with rammed earth? Or compressed earth blocks (CEBs)?
There's no real reason that the names are what they are, but they are. "Rammed earth blocks" is muddled, so you'll have a harder time finding what you're looking for.
If you're thinking of building with rammed earth, I think you could maybe make that jackhammer work. I've never seen it done, but I don't see why not, unless the stroke ends up being too short. When people say "rammed earth," they mean compressing the earth into formworks in place, on the wall.
If you're thinking of making blocks, I think probably not. If you compress the soil inside a form for a block, then you need a way to get the block and the form apart. That's why CEB presses have an expulsion step.
It's also true that uncompressed adobes are completely adequate for building a house.
So... step one, a little clarification of what's the goal.
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