The pilot of the tailwheel-equipped airplane reported that he landed hard and bounced. The pilot further reported that after the bounce, he knew that the left main landing gear had collapsed, and he held the left wing off of the runway until the airplane slowed and the wing stopped producing lift. Subsequently, the airplane veered off the runway to the left and collided with runway signs, which resulted in substantial damage to the horizontal stabilizer.
The pilot reported that the "½ inch fine thread bolt" on the left main landing gear failed during the bounced landing.