Machine Tool Base
Machine tools and other high-precision machines rely upon high stiffness, long-term stability, and excellent damping characteristics of the base material for their static and dynamic performance. The most widely used materials for these structures are cast iron, welded steel fabrications, and natural granite. Due to the lack of long-term stability and very poor damping properties, steel fabricated structures are seldom used where high precision is required. Good-quality cast iron that is stress-relieved and annealed will give the structure dimensional stability, and can be cast into complex shapes, but needs an expensive machining process to form precision surfaces after casting.
Good-quality natural granite is becoming more and more difficult to find, but has a higher damping capacity than cast iron. Again, as with cast iron, the machining of natural granite is labour intensive and expensive.
Read more about this topic: Epoxy Granite
Famous quotes containing the words machine, tool and/or base:
“Much that is natural, to the will must yield.
Men manufacture both machine and soul,
And use what they imperfectly control
To dare a future from the taken routes.”
—Thom Gunn (b. 1929)
“Is it not possible that an individual may be right and a government wrong? Are laws to be enforced simply because they were made? or declared by any number of men to be good, if they are not good? Is there any necessity for a man’s being a tool to perform a deed of which his better nature disapproves?”
—Henry David Thoreau (1817–1862)
“I think it is worse to be poor in mind than in purse, to be stunted and belittled in soul, made a coward, made a liar, made mean and slavish, accustomed to fawn and prevaricate, and “manage” by base arts a husband or a father,—I think this is worse than to be kicked with hobnailed shoes.”
—Frances Power Cobbe (1822–1904)