Step 9: Adding a roundness indicator.
We will just add one screw onto the original roundness indicator. Note that it is preferable to have a roundness indicator that just touches one side of the rim. It is impossible for a rim to be perfectly even on both sides of the rim, so trying to touch both sides at once is both confusing and inaccurate. By making one edge perfectly round, the other with be as round as possible as well.
The first step is simply to put two nuts on our third bolt, about an inch apart.