Do It Yourself “Fraction of an Inch Adding Machine” at Evil Mad Scientist Labs 
The worthy gadgetophiles of Evil Mad Scientist Laboratories have taken a 1950’s “Fraction of an Inch Adding Machine” and turned it into a do it yourself project.
This reminds me of the proportional scale that I still sometimes use. What this one does is to make it simple for you to add fractional measurements (like 1/16″ + 5/64″). Still a useful, old school device in the workshop.
Note: Always remember to Measure Twice, Cut Once.
