I don't have plans for you. The mechanism is called table extension hardware. One place you can get it is www.woodworkershardware.com . The legs can be made removeable by installing a metal bracket on the corners and inserting a hanger bolt into the leg so the legs just bolt on with a single bolt. A hanger bolt has one end that is a lag screw and the other end is a machine bolt.I am building a dining room table for my daughter. She wants it somewhat modern looking and it has to break down so I can ship it to her on the west coast. The real challenge is the underneath mechanism that allows it to expand and put in a leaf. Does anyone out there have plans they can provide?