For years, I have been reading about reusing track if you gently slide a putty knife under the track. Today, when running a train, the locomotive derailed. I watched it run back and forth over the offending spot. I noticed the locomotive and cars rocking slightly. Upon closer inspection, the inside rail had vertical kink in it. It wasn’t where a rail joiner was, so I looked even closer. I must have bent the track when removing it. 2 hours later, I had the offending segment of track cut out and replaced, soldered in place and ballasted.
IF you’re going to reuse track check it thoroughly before you do. 2 minutes of closer checking would have save me 2 hours of replacing it. When the diluted glue dries, I’ll paint and clean the track. Lesson learned.