A couple of weekends ago, I headed to Seattle to attend a workshop taught by Elder G. Jones , an artist who carves wet concrete into beautiful garden art. His work is featured throughout my three books on making concrete forms, so it was an exciting opportunity for me. I have big ideas for making sculpture, incorporating trash, inlaying mosaic, and generally expanding my skills.
So, for my first project at home, I decided to go with the most technically challenging possibility. Mike has been building a wood-fired pizza oven, and the exterior is unfinished. For my first trick, I wanted to enclose the hideous chimney assembly in carved concrete, which meant building a form around an existing structure on an uneven surface.
The form is removed when the concrete is firm enough to hold its shape, but soft enough to carve into. At this point, it feels like carving into a very stiff sand sculpture. You have to be very gentle, or it will come away in chunks. But, it quickly begins to harden, so from here, you just work steadily until it sets up completely, which is about 5-6 hours. (No breaks!)
Yes, I obsess about these things.