An instructor pilot at 500 FT on short final for landing at F45 reported a NMAC with another aircraft entering the traffic pattern at 500 FT and not communicating. The reporter talked with the other pilot later and received a negligent response.

Narrative

Aircraft 1 turned a left base leg for Runway 31 for landing at North County General Aviation Airport (F45) when I noticed Aircraft 2 on a final leg for the same runway. Evasive action was taken to avoid a collision of both aircraft. Aircraft 1 evaded to the right while Aircraft 2 remained on original course. Aircraft 2 began a climb to what looked like 1;000 FT AGL along Runway 31 centerline. I asked Aircraft 2 over the radio; what his intentions were; but received no response. I (Aircraft 1) continued the approach to final for a full stop landing on Runway 31. Aircraft 2 announced over the radio that he was entering the traffic pattern on the downwind of Runway 31. After Aircraft 2 landed; I approached the pilot and asked what his intentions were when he flew the final leg at 500 FT. He said he was over flying the airport to enter the traffic pattern. I informed him that the altitude he chose (500 FT) to enter the pattern nearly caused a mid-air collision. His response was; 'I had you in sight the whole time.' I recommended to him that he not fly the same altitude and course (final leg) as the aircraft that are on approach to land if he wishes to over fly the field. His negligent attitude towards the situation surprised me. He did not seem to care that he had just cut-off an aircraft that was on the approach to land. I think corrective action should be taken to account due to the pilot's negligence for safety.