Tools for makers · 3D printing
Digital calipers
Measures parts to a hundredth of a millimetre. Essential before you design a case, a hole or a mount for an electronic part.
- 23 lessons
What it is for
Calipers have two jaws that close around a part and a screen that shows the size. They measure outside sizes, inside sizes (with the small upper jaws) and depths (with the thin rod at the end).
When you design a part for a sensor, servo or motor, every millimetre matters. Measuring with calipers instead of a ruler is the difference between a part that clicks into place and one that needs filing.
They are also handy for checking printed parts: is the hole really 3 mm, or did the printer make it smaller?
Tips
- Close the jaws and press zero before every measurement.
- Measure a part in two or three places and use the largest value.
- Plastic calipers are cheaper and fine for 3D printing; steel ones last longer.
