When I make the cornett, I oil it several times with vegetable oil, mainly linseed and walnut oil. They are both “drying oils”, which means they will harden in contact with oxygen. This characteristic is used since Ancient times in many fields (paints, varnish, wood and leather treatment, black soap, putty…). The cornett is saturated in oil which “dries” quickly on the surface in contact with the air, but slower “inside” the wood. The time a cornett needs to dry depends on the wood and keeps going on a few months, during the “playing in” period after which the cornett is stabilised.
When one blows into a cornett, the breath causes moisture and warmth to change the hygrometric balance of the oiled wood : it’s of course very different than the workshop conditions. This is why it’s important to “play it in”, just like any wood instrument.
This is also true for cornetts which haven’t been played for a long time.
During theses first times, certain cornetts might suddenly seem “resistant” after having been played a few minutes. This is normal and will disappear after a few weeks.
Playning in timetable :
– 2 first days : 10 to 15 minutes, no longer than 1/2 h a day.
– 10 following days : 20 to 25 minutes, no longer than 1 h a day.
-15 following days : 30 to 45 minutes, no longer than 2 h a day.
Gradually increase the daily playing time, over 3 months.
Wipe the water off the cornett as soon as you stop playing and store it vertically.
Its two main ennemies are heat and moisture. The condensation of breath increases when the cornett is cold. In contact with heat, the wood’s pores open and moisture penetrates in the wood. It swells, which causes tensions, and can eventually lead to a crack or to separating the two halves of the instrument. In extreme cases, microorganisms might develop and damage the wood, modifying the bore and thus the intonation.
This is why one must maintain the initial oil treatment of the instrument.
First of all, always dry your cornett after having played. Store it vertically, and if possible, not in an airproof case.
If the mouthpiece is stuck in the cornett, don’t force it out, but wait untill the cornett has dryed to remove it.
The most important before oiling a cornett is to wait that the instrument dries : otherwise, moisture would be kept inside the wood. It’s fine when you haven’t played for 1 or 2 days, and that the cornett is well ventilated.
Oil makes the wood waterproof. Linseed oil or walnut oil will dry quickly and won’t let a greasy film. If you use linseed oil, be careful to wipe off the whole instrument (inner bore and outside) with a strip of cloth (for example, cloth on a long wooden or plastic stick). The cloth will of course be single-use, as it will turn out to be…. oilcloth.
For an easier care, sweet almond oil can also do (and to a certain extent, any vegetable edible oil). But these are not “drying oils” : the treatment won’t last as long and you will need to do it more often.
The first third of the cornett (from the mouthpiece to the thumb hole) is the most important part to oil.
You will need :
– a container, for example a bottle with a large neck, or a plastic bottle if you cut the neck off. If you want to oil all the cornett, build a “curved tube” with hot-formed pvc tube, or ringed sheath (don’t forget to plug one end !!!)
– vegetable oil (750 ml are enough for a curved cornett).
– Cloths, mops…. for any catastrophe (to avoid any, oil the cornett above a washable surface, or in the bathtub)
– a swab : a small wooden or plastic stick to which you tie a cloth strip. The ones you can find in shops (for bassoons, oboes etc) can do, but only for non-drying oils. In any case, the oiling swab mustn’t be used for any other purpose.
Allow the cornett to dry completely before oiling it.
If you want a “fast oiling”, just pass the oiled swab through the bore.
If you want a deeper oiling, you should let the instrument to soak one day (or night !) in the oil.
Be careful that your oil isn’t too cold (avoid the garage in winter), because it makes it viscous. Oil also feeds the parchment.
Allow the cornett to drain vertically a few hours, and wipe it with a clean cloth inside and outside. Let it dry.
Oiling should be done 4 times a year (or more in case of intensive use), and to complete that by applying sweet almond or walnut oil in the first third of the bore, once a month. Once you get used to it, it takes no more than three minutes.