The pilot reported that when he initially landed the airplane, it touched down hard. The pilot then taxied the airplane without further incident. The pilot stated that when he went to takeoff, during the takeoff ground roll, the right main landing gear collapsed. The right wing and right side elevator contacted the surface and were substantially damaged. Further inspection of the landing gear revealed that the failure occurred at a weld point. The pilot indicated a total time of 1,569 hours on the part.