metrology

A lot of measuring techniques involve the use of cylindrical rods, for ex, to measure dove tail with a micrometer, one can place rods at both ends, measure the distance between the rods, subtract the diameters. I'm not equipped to turn rods as accurately as I'd like (unfortunately), so I'd...

I have rough cut 3x2 rectangular structural steel tubes to slightly longer than my desired length. I would like to scribe a line as a guide to grind, file and sand them down such that the ends are as near as 90 degrees to the length as I can manage. Using a machinists t-square works fine for...

Today, May 20th, Is World Metrology Day! http://www.worldmetrologyday.org Let the celebration begin and continue into the wee hours of the morning....