Do not sand them. And beware the over simplified methods which you may find on the web. The Spizzichino vat is legendary! Thanks orangemi.
Yes, I have successfully used vinegar and salt to take the shine off cymbals. It is a mild acid and it acts as either a cleaning agent or a patina generating solution depending on how you use it. This is the basic difference between a list of ingredients and a full recipe which includes the method. I've used other ingredients and recipes as well as part of my experimentation. Note that it is oxidation which does the work so you don't just put them in a bath of some solution to get patina. You have to bring them in and out so they have contact with air.
Here is a tried and true recipe thanks to Craig Lauritsen. His formula is vinegar, lemon juice and salt (roughly a teaspoon per 50 ml), with red wine and or port (more will make a browner colored patina). The addition of a little black tea will also give a browner finish.
[list]Clean the cymbal vigorously with the patina agent and a rag and let it dry.
[*]Then spray on the patina solution and use a small roller to get a nice even coat.
[*]Let it dry and reapply. The trick is to spray on the correct amount of patina. Too wet and it will drip or build up in some areas and create a less even finish. Too dry and air bubbles will form from the roller and create a less even finish.
[*]After the solution has dried again, it may be necessary to do another application if there are coloration differences due to evenness.
[*]Once the patina is as pronounced as I want it (2 - 5 days, depending on heat and whether I can let it sit in the sun for a day or two), I clean the cymbal with a vinegar soaked rag and then rinse with water.
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This gets you this sort of look on a brand new cymbal when you take it far enough:
[img]http://black.net.nz/cym2014/CL-patina1.jpg[/img]
It takes patience to do the number of "apply and dry" iterations required to get this level of effect. In my experiments I've put on, removed, and put back on a number of different patina styles on a "sacrificial" Chinese (Dream) B20 crash. I've even put a patina on half so I could compare the two sides. All in the name of patina science. Note this isn't the cymbal pictured above.