A small but important part of the manufacturing process involves making certain the yarn is strong enough, particularly for the warp. Testing can be done quickly with a couple of machines.

First, a specific length of yarn is taken off the spindle. This machine counts to the proper number of revolutions and stops, thus producing the same length of yarn for each test.

Here the gauge shows this batch broke at about 99.5 kilos - nice and close
and well within accepted tolerance.

This batch of yarn can be put on a loom to have knots tied on it.