infographics

The slide rule may be a quaint anachronism in this age of ubiquitous computing, but there’s still a place for the slide chart, the volvelle, the nomogram, and other hand-held “paper computers.” These are still published by a few companies, and are a handy source of on-the-spot reference data, particularly in field or workshop environments that may be inhospitable to or inconvenient for electronic devices. Slide charts containing key screw, bolt, and nut data have been around for decades, and the folks at Great Innovations identify TAD’s Universal Reference Calculator, discontinued in the mid 1990s, as inspiration for their chart.