"Measurement Sticks" Bar Gauge ~8.25 - 16 inches (~210mm - 410mm)

A simple two-piece interlocking, adjustable beam bar gauge that can be used to transfer and take accurate internal measurements of enclosed spaces that  you can't cleanly measure with a tape measure.  As provided you can take measurements between  8.25 to 16 inches (or between 210mm and 410mm.)  You can cut the part down if you need smaller, or scale up in Z size if you need longer measurements (assuming your printer can print higher, note that the print will be exponentially more difficult as you make it taller.)

Place the bar gauge between the surfaces, expand until the faces touch each piece being measured, hold the bar gauge in position, remove from enclosed space, measure with a tape measure to find the accurate distance.

Both parts are printed vertically on the printbed, so don't be shy about applying a thin layer of glue stick to your bed to help them adhere.