Protect From Dryness
Extremely dry temperature is not good for wood instruments either, and you should do what you can to protect your instrument from drying out. Hot, dry rooms in winter should be avoided. Don’t leave your instrument near a radiator or hot air register. Extremely dry temperatures can be partially offset if you will carry a humidifier in your case. Your music dealer can supply this.
When your wood instrument becomes very dry, retaining rings on bell and on tenon receivers become loose and drop off, key posts become loose and twist, causing keys to bind. A quick way to tighten a retaining ring is to stretch a piece of cheesecloth over the tenon receiver or bell, push the ring over the cheesecloth, and then cut away all the cloth which shows. A quick way to tighten a loose post is to take some emery powder or some sand off a piece of fine sandpaper, unscrew the post, drop some of this powder or fine sand under the base of the post, and screw the post back in place. This will hold the post in place for some time. Of course, the best way is to drill a small hole in the base of the post and drive a pin through this hole into the wood. Some clarinets have a post lock which avoids all this trouble with posts in dry weather.
Repair a Crack
Wood is a product of nature and cannot be standardized. From the time the grenadilla wood log is cut from the wasteland of Mozambique or Madagascar, South Africa, up to the finished clarinet, fully 90% of the wood has been discarded through expert saving, careful selection, long years of curing, treating in oil, and repeated inspection. The wood in fine clarinets is as near perfect as human skill and experience can get it. And yet a certain percentage of clarinets will crack in spite of everything, and even though they receive expert care while in use.
If your clarinet does crack, don’t be unduly alarmed. Experienced professional clarinet players think nothing of it and they consider the clarinet after it is repaired to be less liable to crack again than it was before it was repaired. Many fine old clarinets are pinned in several places.