I'm with Vito. Doesn't matter whether you call them feathers and wedges, pins and feathers, or shims and wedges -- it's the same system. What you do, is snap a chalk line along where you want the stone to break, and then drill a hole about 2 or 3 inches deep every 3 or 4 inches. You can use either an old-fashioned star drill and a hand-drilling hammer (looks like a small sledgehammer with a short handle), or a pneumatic driver with a star bit. When you have a line of holes completed, put the feathers/shims parallel to the line you chalked and insert the pins/wedges. Now just go along the line and tap -- just tap it, don't hit it hard -- each one in succession. When you get to the end, go back to the beginning and tap each one again. As you are doing this, the internal pressure is building up, and once it exceeds the capacity of that rock to hold together, that rock will give a snap and break right along the line of holes. Then pick up your iron pieces and start again. There is also a product on the market called Dex-pan; once you have the holes drilled, you simply pour the Dex-pan in the holes. When exposed to air, the Dex-pan starts to expand, and eventually will snap the rock open like the pins and feathers do. Unlike iron tools, however, it's not re-usable. The feathers and wedges/pins and feathers (or whatever you want to call them) come in different sizes; I would get the smallest diameter that will still accomplish your purpose. (It's easier to drill a small hole than a big one). We have been using this technique on Maine granite for decades, and if it'll split eastern granite, that ol' sandstone should be a pushover. Feel free to write with any questions. -- Maine Fordson
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