When I became a BAR one of the first rockets that I tried to build was an Estes Solar Flare. About the time that I started building it, the family got a new puppy who I found out really liked to eat balsa and cardboard Attempt#2: Bought a new kit and tried again. While trying to insert the 13mm motor mount in the sustainer, the wood glue grabbed before I got it into place, and I damaged the tube trying to get it out. Attempt #3: Found a piece of (25 year old) 13mm tube from the remnants of my Estes Javelin that got partially crushed over the years and decided to use that as a replacement. The rocket looked good on the launch pad, and lifted off straight, but when the rocket staged, that old tube shredded and the motor went up through the sustainer shredding the recovery system. ALSO - One of the bystanders said that they thought they had heard the motor CATO, but I was sure they must have been mistaken... Attempt #4: Rebuilt the rocket again and tried again. Rocket launched fine, staged fine... BOOM. CATO of the second stage motor (from the same batch) spitting the nozzle out the back end, hitting two of the fins on the booster and breaking them. Attempt #5: Rocket has been rebuilt again, but has not been launched... YET!