To oil, or not to oil?
For decades, I’ve heard many opinions about oiling woodwind instruments, specifically clarinets and oboes, from players and teachers. One professor told me years ago to paint the bore of a new instrument with oil daily until it saturates. He claimed it would never need oiling again. Another said to coat the entire body inside and out every month for a year, then twice a year thereafter. A clarinet player once told me he never oiled his instruments because he thought the “break-in” process was bogus. An oboist I knew had a long and specific playing schedule she religiously followed to break-in a new oboe. This also included regular bore oiling. Techs have many varied opinions on this subject. Some will swipe a little oil down the bore, while others go through an elaborate process that involves soaking the wood pieces for days in a heated immersion tank of oil. There are a lot of variations to choose from. So which one is right? Like a lot of techs, I have an opinion, so here goes.
Let’s start by looking at the wood itself.
African Blackwood, also known as Grenandilla and Mpingo, is the primary wood used in clarinet and oboe making. It is a high density hardwood that turns well on a lathe. It holds its shape and stability after becoming an instrument. The tree grows mainly in the Tanzania region of Africa and is their primary cash crop and principal export.
It grows gnarly and twisted in this dry desert area. Because of this, it is a very oily wood to begin with as this helps the tree retain the water it needs to live. The process starts with felling the tree, cutting the wood into usable billets, and coating them in a sealing wax to prevent oil and humidity loss. Some manufacturers kiln dry and age their billets up to ten years before turning into an instrument.
After the wood becomes an instrument, there is a danger of cracking. This, in my opinion and research, has little to do with oil. Cracking has more to do with the condition of the wood itself from the harvest, the factory processes, and temperature/humidity exposure. There are weak spots that are grown into the grain of the wood at the ring points, and this is where cracking is more likely to happen. Oiling or not oiling the wood will not affect it. If the wood is stressed, it will crack, and the player has little control over it.
The primary thought for many players, teachers, and techs is that oiling wood instruments prevents them from cracking. Not quite. Wood cracks for many reasons, but the main one is extreme and rapid temperature changes along with a moisture imbalance. The oil content has nothing to do with this kind of environmental stress. Wood that is dry to the point of desiccation, is not necessarily missing oil. It’s missing water. Hydration and oiling are two different ideas. However, they are related.
All woods, whether hard or soft, are hygroscopic. This means they will absorb and release water as needed to balance their environment. The equilibrium moisture content (EMC) is more critical than the amount of oil. Wood density, cell wall moisture level, bore dimensions, and the elasticity of the wood all have more effect on pitch production and resonance than oil content. Maintaining the balance of moisture in the wood’s cell walls is where oiling comes into play. Oil is more or less a preventative for water loss and will help slow or prevent the breakdown decay of fibers in the instrument’s bore.
Ever hear a player say their instrument is “blown-out?” I believe this is because of an EMC imbalance rather than oil content. This topic is a major rabbit hole to explore, but the focus here is oiling or not oiling wood instruments. My opinion? I do not think oiling a new instrument is necessary. A steady humidity/hydration level will do more for the instrument than oiling. A hygrometer in the house, band room, or instrument locker room will measure air humidity and indicate what environment the instrument needs. Ideally, the level should be between 40-50 percent.
Where oiling is necessary is on older, well-loved instruments. Specifically, ones of vintage age. How to judge? Look in the bore. Is it dry and pithy, or is it solid and shiny? Does the outside look grainy and shrunken? Is the wood dull?
If the wood is shiny, the bore solid, or if there is a brown residue that appears on the pads, the wood has oil in it and probably does not need more. Again, it will not hurt the wood if the player oils it. It’s a good idea on aging instruments (around eight to ten years) to put a bi-yearly layer of oil in the bore. This will help slow the breakdown of wood fibers and allow the instrument to keep its resonant life a little longer.
As a side note, leaving residual moisture from playing is not a good idea. Saliva is more than just water. It contains minerals, acids, enzymes, mucus, food particles, and proteins. None of this is a good coating to leave in the bore of an instrument and can cause several forms of damage. The rule? Whether it’s two minutes of playing or two hours of playing, swab it out before storing.
If in doubt about the need for oiling, try a test run. Place a dot of oil on the inside of the instrument bore, preferably near the middle tenon. Let it sit overnight and see what kind of residue is left. If the wood sucks up the oil like it’s starving, there is the answer. The best oil to use for testing and home oiling is sweet almond oil available at most grocery stores. Make sure it’s pure oil and not a blend. If the test is successful, it’s time to oil.
If the instrument is completely dried out, my recommendation is to take the instrument to a tech. The best way of oiling at this point is heated immersion, which means the keys, rods, springs, etc, need to come off, and the body needs to be treated. I have a specific blend of conditioning oils for this purpose, and it is a long process.
The home remedy is to apply thin coats of oil to the bore daily with a dedicated swab or large turkey feather. Dip the swab or feather in oil and swipe through once a day for a few weeks or until the oil stops being absorbed into the wood. The emphasis here is thin applications only as too much oil at one time can cause problems for the pads. Wiping thin coats of oil to the outside of the instrument is possible, but care must be taken to avoid getting the pads and corks saturated and making more repair work. For preventative maintenance, use this technique twice a year. Easter and Christmas to make remembering easier.
There is a lot more to be said about the science of wood. Hydration, oil content, capillary movement, absorption rates, EMC balance; enough to fill an entire warren rather than just going down a rabbit hole. For the player and teacher, if the question is to oil or not to oil, go ahead. It may not prevent cracks, but it certainly won’t hurt anything. The better bet is to humidify in addition to oiling.