Working with round wood can be a difficult task since most clamps cannot fit around the wood without severely damaging it. Creating your own clamp will prevent damage to the wood while keeping it in place.
Cut the valve off the bicycle inner tube.
Cut the bicycle inner tube in half, width-wise.
Cut the bicycle inner tube in half, lengthwise.
Wrap one strip of the inner tube around the round wood. Stretch the rubber while you wrap it around the wood so that it is snug and acts as a strap.
Clamp the rubber strap to the edge of the table with a spring clamp.
Super glue the two strips together for a longer strap.