I used to work for Hermle Machine (German Co. Here in Milwaukee area). They now build all of their machines with the composite Granite bases. They are cast in an almost finished state. They machine about 5-6 surfaces flat and their ready to start building. Top quality stuff, +/_ .00005 precision (that's 1/2 of a Ten Thousanths of an inch). But in the right environment they'll do +/_ .00003 all day long. The Composite Granite is vibration stable but also has excellent thermal properties.
Mike Mattera
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