Drill 3 holes of 3" diameter through the table surface for the pendulums to hang through. The hole for the rotary pendulum should be centered in a corner about 8" from each side just clear of the leg brace underneath. The other two holes should be aligned near the opposite edges, about 8" from the common side, and 3" from the other. You'll need a special large circular drill bit for this. Alternatively you can first drill a smaller hole, and then cut a wider opening with a jigsaw.