Chrome plating problem- wavy metal

I recently had the exhaust system for a vintage motorcycle (steel pipes and rolled tapered steel muffler body) re-plated and when it was returned the muffler metal was slightly wrinkled and wavy. What went wrong?

I would bet you had an over aggressive buffer working on the pipe. You can actually warp and put waves in thin metal like that if you get it too hot when you are buffing it. Only way to fix it would be to strip the chrome off, re-copper for a couple of cycles of 90 min each with block sanding in between. Then continue with buffing, re-nickel, and finally chrome. Try and find a plating shop that will tell you what they will do to fix it. don't simply give it to them and ask them to fix it.