On July 4, 2005, at 0745 central daylight time, a Piper PA-22-180, N5807Z, experienced a gear collapse during a bounced landing on runway 18 (4,000 feet by 75 feet, asphalt) at the Porter County Municipal Airport (VPZ), Valparaiso, Indiana. The student pilot was not injured. The airplane was substantially damaged. The 14 Code of Federal Regulations Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The flight originated at VPZ at 0730. The pilot stated he was practicing takeoffs and landings when the accident occurred. He stated that the first landing was "fine." The pilot stated that during the second landing touchdown, he heard a "pop." The airplane became airborne again and the right wing raised slightly. He stated he corrected with aileron and the left main gear collapsed as the airplane touched down again. The pilot reported the left wing and the propeller contacted the runway prior to the airplane coming to a stop. The airplane had been converted to a tail wheel aircraft in 1982. The airplane had been flown 84 hours since the conversion. The airplane was examined by an inspector from the Federal Aviation Administration South Bend, Indiana Flight Standards District Office. The inspector reported the landing gear strut was compressed and the gear was folded inward under the fuselage. He also stated the axle was pushed through the wheel and the wheel bearings were broken.