Digital Caliper thickness checker
For people who want a fast, easy way to measure thickness and record it on the spot, I tacked stainless steel caliper jaw extensions to a $20 Harbor Freight digital caliper. Notice you can zero the jaws easily before making measurements.
Below is a closeup of the quick and dirty weld job plus you see the off-on button and the zero button. The blue button at the top toggles the caliper between inches and mm.
The tips are brought together first, then the zero button is pushed. After that, you can make as many measurements as you wish and map them.