Step 5: Mount Support Pole
With a desk shelf these constraints were very easy to satisfy, I simply used a hole saw to cut through the bottom, and attached a plate to the shelf. The plate was only required because I could not access both levels with the hole saw.
On top of the shelf plate sits the height setting ring; two cap screws secure this ring to the pole to ensure it does not slip through the desk. Directly on top of the height setting ring sits the first of the three main pivot plates.
Once these parts are assembled, give it all a firm push/pull just to make sure it is strong enough, and be sure to twist the pole to make sure it is not binding somewhere. Both of these things are a lot easier to fix now than later!