Wall Thickness Caliper

This is a custom wall thickness caliper designed for use with 20x40 V-slot aluminum profiles and a few 3D-printed parts.
It’s especially useful when renovating or inspecting a house, as it makes it easy to measure wall thickness around windowsills, door frames, and other openings where a regular caliper won’t fit.

Jaw width: 120 mm – ideal for getting around obstacles and into narrow spaces.
Adjustable length: Depends on the extrusion you use. With 300 mm profiles, you can measure up to ~100 mm wall thickness.
Tape measure integration: Add a 10 mm self-adhesive tape measure to make readings quick and accurate.

Materials Needed:

*28 × M5 8 mm hex bolts
*28 × M5 T-nuts
*4 × M5 20–30 mm countersunk screws
*2 × 20×40 V-slot profiles (minimum length 300 mm, longer for thicker walls)
*1 × ~10 mm wide self-adhesive tape measure