For your trumpet to play properly, you must lubricate the valves with trumpet valve oil on a regular basis. Choosing the best valve oil may involve some trial error as it all depends on your preferences and what kind of trumpet you play. For tight valves and a very quick response, a light valve oil is the best choice. For older or looser valves, a heavy oil is often necessary. Valve oil is relatively inexpensive and readily available in music stores, online, and through catalogs.
There are two basic types of valve oil: natural and synthetic. Natural valve oil is petroleum based. Synthetic oil is typically more expensive than natural oil, and it is not as commonly used. Some experts claim that synthetic works well with newer instruments and that natural oil works better with older instruments, but in many cases, choice of oil is a personal preference.
Newer trumpets typically have tight fitting valves that work well with thin oils. Vintage trumpets that have seen a lot of use usually have more space in the valve and work better with a thicker oil. In some cases, manufacturers rate their trumpet valve oil as heavy, light, or regular. This refers to the thickness of the oil. Heavy oils are typically used with looser valves and light oils with tight fitting valves.
The valve oil, particularly its thickness, will effect how the valve reacts. Some musicians prefer their valves to have slight resistance, while others want a valve that slips up and down with the lightest touch. The only way to find out what oil is right for you and your instrument is to try different types.
Valves should be cleaned thoroughly before trying a new trumpet valve oil. Mixing natural oils can cause the valves to stick and mixing synthetic and natural oils can cause damaging corrosion to the instrument. Corrosion usually requires a chemical treatment to remove, which is costly and must be performed by a professional instrument repairman.
Although it may seem trivial, it is important to consider the packaging of the trumpet valve oil. Most comes in some type of bottle, but the lid or cap can make a difference in the ease of dispensing the liquid. Consider the few minutes before a performance or during rehearsal, and think about whether the bottle would be easy to dispense oil from. Even the best valve oil, if it cannot be dispensed easily, will go unused.
Many new trumpets have a small bottle of trumpet valve oil included in the instrument case. Advanced players agree that this oil is typically not high quality, usually doesn't last very long, and provides unsatisfactory results. Since even good valve oil is relatively inexpensive, it is worth it to throw out the valve oil that comes with the instrument and purchase a higher quality product.