This is a baseplate with an angled protrusion that engages at the lead angle of the lead screw. A pointer carries a similar protrusion and can pivot, lengthening or shortening the pitch. It is not an accurate tool for measuring absolute pitch unless you can calibrate it, but it will show the pitch difference between multiple screws. Print with PLA. Use an M3 screw. Run the screw in from the back of the baseplate and turn it multiple times so it turns freely, but with no slop. Thread the screw into the pointer so the pointer moves freely but has minimal slop. Highlight the three index marks and the end of the pointer with a silver Sharpie. Be sure to have the length of the baseplate in contact with the lead screw when measuring. The marks, if I calculated correctly, are plus and minus 1/2 percent of the pitch. No guarantees are given or implied as to how well this will work. EXPERIMENTAL DEVICE!

In my photo, the pointer is a bit off scale, but all my screws matched quite closely.