I've recently started playing horn and picked up a pre-WWII Elkhart Conn 6D off of ebay for $500. It was in pretty rough shape, so I sent it in and got it completely refurbished. I sent it down to a place in Wisconsin called "Badger State Repair."

While it was there they completely took it apart and cleaned it. It was a pretty intense cleaning, took it all apart, stripped whatever lacquer was left on it, gave it a chemical bath, polished it, re-lacquered it, and soldered everything back together. The only thing they had to completely replace was the leadpipe, but other than that the horn is completely original.

Now I've started to notice some little bubbles starting to appear in some places on the lacquer. They almost look like red rot, but it just went through all of that (expensive) cleaning just a year ago and I'd assume that they'd have caught any major problems like that and replaced the parts. They even said that they put some kind of heavy-duty, extra resilient lacquer on it, so I don't know why it's doing this.

The bubbles are pretty small, not even the size of a pencil eraser. They're raised and rough, and if I scratch at them, the lacquer itself will wear away leaving a slightly discolored bare spot behind. Some of them are a darker yellowish color while some of them are more of a red-orange color, and a couple of them are even more of white color. Only one appeared at first and I wasn't too concerned but then more started appearing around the same area. They aren't even in a place that I touch with my hands that often, they're on a pipe that I occasionally pull out to empty spit from my horn.

Should I be worried about them? Are they just minor damage to the lacquer or is it damage to the horn and the metal itself? I'm planning on taking it in to a shop to have a technician actually look at it, but I'm pretty busy and want at least some kind of opinion until I can get the time to take it in.