I am currently on a tour with my school band in Austria. I own a torpedo bag, I placed a hair band on my horn to prevent my slides from potentially falling out during transportation. Today, when I took out my horn, I noticed a small chip on the outside of my third valve casing, as well as light scratches over where I had placed the hair band. I pressed the third valve and it got stuck. I was able to get it to move with valve oil, though it was still sticky and slow. After a while it started making a scraping sound. I'm afraid that the chip may actually be a dent in the valve casing. However I do not know how I got it. My only possible explanation is that the glue (quite hard and pointy) that fuses the ends of the hair band was pushed into the casing when I slid the horn into the torpedo bag. So I have a few concerns here:
1) I feel like I am damaging the valve every time I press the valve down, and I still have four concerts left.
2) Should I have this repaired when I get back? If I were to get it repaired, would it ruin the compression? (They would probably have to sand the inside of the casing, right?) Is it better to leave it as is and have the valve scratch until it doesn't scratch?