One of the tools in my arsenal travels with me everywhere. As a watchmaker I have many solvents and cleaners at my disposal. I use them all sparingly and in accordance with safe practices.

For cleaning watch movements I use L&R Ultrasonic Cleaner and L&R Ultrasonic Rinse. The cleaner is Ammonia based, the rinse has a high content of Naphtha. At the bench I have trichloroethylene, hexane, denatured alcohol & acetone. For cases I use an ammonia free detergent in water. I’m sure there are a dozen other solvents around, each with their specific purpose but sometimes the best agent is saliva.

For removing gunk from crystals a little spit on a rag often works better than all of the above. I suppose its the enzymes, but I really don’t know any of the science behind it. Sometimes on a dial some fog from your breath does the trick. It’s amazing how the simplest (and perhaps safest) cleaners sometimes work the best.