Since the early 1980s, the development of CMMs that incorporate “virtual accuracy” has had some significant ramifications for users. Originally, error mapping involved software used to aid linear accuracy calibration of machine axes. Using this method, a CMM’s software scales are adjusted by using scale tensioners. Because this allows scale accuracy to be equated with a laser interferometer readout, it improves the CMM’s accuracy without compromising its mechanical qualities..."

Take a master ring used to set a reference on an air plug as an example. The standards define the physical dimensions, the class of the size (that is, how close to the specified size the ring is), the surface finish and form of the ring, squareness of the hole, roundness and cylindricity. Because of these defined conditions, the master ring can be used at any orientation or height along the axis of the ring. While the certification for the size of the ring will typically be measured at three heights at the 12 and 3 o’clock positions, there are form definitions that ensure that the diameter is the same within the roundness specifications that are applied to the ring. This makes it possible to use the ring as a reference anywhere..."

Character Quote of the Month

"Failure is the opportunity to begin again more intelligently." - Moshe Arens

While the products are more powerful, smaller and less expensive, one thing hasn’t changed: like any other gage, they are no better than the way they are used. Here is a checklist to follow when using a portable surface finish gage..."

 

Generosity is a means of influence. Used to subvert morality by influencing someone’s actions, we call it a bribe. Generosity can encourage a worthy pursuit, however, as illustrated in the story of Benjamin West, 'The Father of American Fine Arts.'

The Generosity of a Mother’s Praise

 On a warm summer morning in 1745, Benjamin’s mother and older sister went out to the garden for flowers. Six-year-old Benjamin was left to watch his newborn niece and to keep flies away from her as she slept.
Benjamin forgot about swatting flies, however. He was so intrigued by the little girl’s expression that he retrieved his father’s ink and drew a childish portrait of her sleeping grin.
When his mother returned, Benjamin sheepishly hid the picture, fearing he had been naughty. Upon finding the picture, however, his mother praised her fine little artist. Thus young Benjamin continued to draw