People ask me, "How do you connect pieces of the SketchUp model at their appropriate connection points? And, how do you connect a round component - like a drawer knob - to the door or drawer at the proper position?"
Let's use a drawer as an example to show how connections are made. Remember, it's easier to do these precise connections when you've used SketchUp's Components for the pieces of your furniture.

Step 1: Let's isolate the Drawer Front and one Side for precise connection. Find common points of connection for the two components.

Step 2: Use Move Tool, connect to the specific connect point on the Side, move the Side to specific connect point on Drawer Front.

Step 3; Connecting the Knob at a precise location is more difficult. Any round component does not have the intersecting edges that define connect points. So you have to make some defined explicit points for common connection.

Step 4: Make an intersection point on the Knob.

Step 5: Use X-ray view to help locate the points of interconnection.

Step 6: All done

Tim Killen
http://killenwood.com