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Hello and Welcome!

The aim in starting this Index is to make it easier for the public to follow the <A href="http://www.cnczone.com/forums/showthread.php?t=30155">main E/G thread</A> which currently stands at 124 pages.






In <A href="http://www.cnczone.com/forums/showthread.php?t=30155">"Epoxy-Granite machine bases"</A> thread, we began investigating the possibility of using composite castings as bases for various machine tools.

(Read <A href="http://www.cnczone.com/forums/showpost.php?p=273150&postcount=541">this</A> first).




Pictured above: Mikron HSM 600 - Monoblock Epoxy Composite Frame, True High Speed Machining, Feed Rate 1575ipm & 1.0g of Acceleration, Spindle max 32 kW.



What Is Epoxy Granite?

Bases of polymer concrete or epoxy-granite as a substitute for cast iron are manufactured out of compact packed rocks in various sizes, fillers and a low percentage of epoxy binder. The extraordinary temperature stability and damping characteristics of polymer concrete are about 6 times higher than those of cast iron.

Developed by Swiss machinery makers in the 1980s, composite bases have found limited use in standard machinery but are increasingly being used on special machine tools requiring high precision and on other special machinery uses. In High Speed Machining, polymer concrete has become state of the art for all non moving components of the machine structure, such like beds, bridges and columns.

While original formulations of polymer composites came from concrete filling of machine tool bases and included concrete, more recent formulations consist mainly of quartz or granite materials in an epoxy composite. Thus, the name change from polymer concrete to epoxy-granite (E/G).


What About Portland Cement?

Portland cement-based concrete is not dimensionally stable enough, due to its own internal structural variations with time and its hygroscopic nature, to allow it to be used for the main structure of a precision machine tool. Properly cured reinforced concrete on a stable, dry subgrade can provide a reasonably stable foundation only for very large machines that are not self-supporting.



This is what you will find in the <A href="http://www.cnczone.com/forums/showthread.php?t=30155"> main E/G thread</A>:




While my own experiments have not been particularly successful, my findings tend to agree with general E/G idea. Once you try it, you will never go back. There is simply nothing like it!




Epoxy also makes an excellent <A href=" http://www.cnczone.com/forums/showpost.php?p=282777&postcount=839">surface plate</A>. Great way to get an accurate table surface to measure and build your machine on.



All this and more in our <A href="http://www.cnczone.com/forums/showthread.php?t=30155">main E/G thread</A>! So sit back and relax, and let us guide you through it.

(Important: Do not post questions in this thread. It's for indexing purposes only).

Thanks!
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