So here’s our example of finish plastering using earthen plaster on this wattle and daub sample. Several people did this. You just use the edge of your hand right here. Just put on a thin layer. So the edge of your hand becomes like a trowel. You could do this with a trowel, but we’re using our hands to show the simplest way. Same basic mixture (as first coat) except the straw is chopped into smaller pieces. Be careful not to use too much moisture or it will crack. Use fairly thin layers on the finish coats. You could put one or two more on top of this. You can also take a yogurt lid or piece of plastic and you can go around and make it smoother and smoother. That’s it, very simple. You don’t need to use a trowel, but this is a good shape to have (curved trowel). And a pointed trowel like this is good for along edges and in corners. I’m demonstrating this to show how you can flatten it — get it flatter and better with a trowel. You’re basically just cutting away — see — you cut away from the high places as you’re troweling and you can put that into a low spot. Like here’s a low spot. So you can work it. Get your trowel wet and you can continue to smooth it as much as you want. It could be as smooth as glass. And this is only the second coat. You can keep doing this over and over until it’s polished. (Or use a less than perfect finish.)
So we’re just playing around here just a little bit to demonstrate the possibilities. But you can see it’s getting harder and flatter, smoother and what’s happening is you’re removing material from the high places, depositing it in the low areas, so you’re flattening it a little at a time. The clay platelets (particles) are realigning. You’re compressing the clay platelets and creating a harder, stronger surface. Of course a professional would do this same thing but much faster, but this is the basic process that they’re using.
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