Another thread regarding clasps for case making and a comment that few had seen a flute case key lead me to this: I have an antique English flute case with a broken clasp. The only mechanism for opening this case was the key, so some time long ago someone had to break it open to get inside. My ever so inelegant solution to this was to make two large “rubber bands” out of one inch elastic. In my case I repurposed some elastic from a pair of my son’s shorts so they are a cheerful red.
Anyone else have a case that only opens with a key?