This is not a joke.A cat or dog walking across a bridge can get the bridge to resonating.I have a pre-1958 20" UFIP ride cymbal. When I do a ride beat, even a medium tempo, the cymbal starts shaking and reverberating or resonating making some kind of strange sound you would not want a cymbal to make. The cymbal has been this way since I purchased the set in the middle '60's.What is the issue?Is there anything that can be done to the cymbal, like a re-cut or re-groove to correct this issue?
"making some kind of strange sound you would not want a cymbal to make".
A sound file would be helpful and perhaps a better description of the effect you're hearing.
Perhaps what your hearing is a wash under the sticking that jazz drummers might love. If you don't like it. Sell it. Don't modify it. First it would cost you money to do so, second its more than likely it would not sound better to your ears, and finally if this is really a good cymbal you will have destoyed any value it had.
The shaking you talk about sounds like a wobble, which usually occurs with thinner cymbals and is often prized by many jazz players.
I don't know what UFIP made in the 50's. Whether this was a good cymbal to start with, whether it used cast bronze, whether it was hand hammered. Others here I suspect can tell you more about vintage UFIPs