Don't try this with a vernier!
My Six Inch Calculator
© Frank Ford 2008; Photos by FF, 2005

Like much of what I write about, this is pretty simple stuff; I hope it's interesting and fun.

Seems like years ago I was much better at simple calcuations in my head, but half a lifetime surrounded by pocket calculators changed all that. (I'm guessing age may not be helping, either.) Now, I find myself reaching for a calculator all the time in my shop.  When it's not handy for simple addition and subtraction, I sometimes do the calculation using my digital caliper, like this -

Here, I've made a measurement, and I'd like to subtract 0.125" from it:


Without moving the slide, I zero the reading.


Now, I close the slide to indicate negative 0.125"


Zero again:


When I slam the jaws shut, I have my calculated result:

Hey, it works for me. . .

Back to Machining Index