Cracks In Wooden Instruments - Do They Matter? CASS Article

Cracks In Wooden Instruments - Do They Matter?

The vexed question of cracks in wooden clarinets and oboes arises frequently and can be the cause of much anxiety for players or potential purchasers of instruments. A bit of background may help to bridge a gap in the perception of cracking, its reason for occurrence and its relevance to performance. I wish to state that this blog entry is a sharing of information and a relation of my experience over many years - it is not a scientific treatise and should not be interpreted as such.

The African blackwood Grenadilla, latin name Dalbergia melanoxylon, or mpingo in Swahili, which is chosen for most wooden instruments is among the densest wood available for instrument manufacture. It has been the wood of choice for centuries, prized for its stability, workability and resonance for the purpose. It is still a piece of wood. The wood has a grain and the grain is a natural occurrence.  Blackwood grows very slowly (hence its density) and with a very close grain that helps to resist motion and absorption of moisture. The best wood is quite rare and supplies are diminishing worldwide so manufacturers take great care of their wood stocks and use them very efficiently.

Once the wood is harvested, billets are cut from which the joints, barrels and bells will eventually be manufactured. Since the late 1970's until the present day the billets are subjected to a heat and pressure treatment by the manufacturers to stabilise them and further reduce the likelihood of cracks occurring. For instruments manufactured before this technology came into use oil soaking was employed to the same end.

FYI - This is why oiling is not often recommended for modern instruments as it tends to be ineffectual and is more likely to cause damage to pads than real protection to the wood. For older instruments oiling with almond or linseed oil can be very helpful but the caveat of taking great care not to oil in excess must be observed. Oil will shorten the life of any pad with which it comes into contact. If you do wish to oil an instrument use a dedicated swab, chamois leather if available, and only apply a small quantity of oil at a time. Oil the inside of the instrument, as this is where the oil has a preventative role stopping moisture absorption. If the outside of the instrument has a 'tired' or dry look about it some oil may be applied to 'liven up' the appearance but do exercise caution.

Should the wood grain on the surface of an instrument 'open up', either following use or due to climate changes, it is a sign of the wood releasing tension and if this is sorted out by a skilled repairer, usually by the application of modern 'super glue(s)', the wood will actually be more stable than previously and the repaired 'crack' will be made invisible. If the crack opens up to a greater extent and goes through the wood entirely it may require more extensive attention including the possibility of 'pinning' to stabilise it - this is the more serious insertion of a screw mechanism into the wood which is used to draw together the walls of the crack. Prior to the advent of super glue technology this was the common practice to address cracks. If the crack goes through to the edge of a tone hole sealing with glue may work and should be tried initially but it may be necessary for an experienced repairer to insert a liner, usually made of plastic, and remake the tone hole itself. Once this is done the instrument should perform 'as good as new' and will be even less likely to have a similar problem in the same are in the future.

I have played on clarinets and oboes that have had cracks both sealed and pinned for many years with no loss of performance or my confidence in them. When a crack happens on a new instrument despite the best efforts of the manufacturer, if it still under warranty (typically a 1 year warranty is standard with exceptional manufacturers offering a 2 year warranty against cracking) in most cases the instrument will be received back by the manufacturer to have the crack assessed for either repair or  joint replacement. If an instrument is out of warranty an experienced repairer should be able to offer the same attention and the same likelihood of a successful repair to the instrument.

Players can dramatically reduce the occurrence of cracking by observing some very simple care suggestions:

• Use the swab frequently during practice sessions and performances
• Pull it through slowly to allow for absorption of moisture - do not 'whip it though'
• Blow across opened upper joint tone and trill key holes to dislodge moisture
• Clean the inside of joint recesses to remove accumulated moisture
• Use cork grease regularly as this helps both assembly and to seal joint tenons
• Avoid moisture extremes wherever possible
• Avoid 'stressing' cold instruments with warm air, always bring to room temperature before use
• Never store instruments in cold conditions
• Avoid direct sunlight or any heat source that could damage the wood
• Examine your instrument regularly but without anxiety - just get to know it's natural condition
• If a grain is noticed to be opening up have it seen to straight away and you will likely have no further trouble

In my experience it is extremely rare that a grain 'crack' has not been able to be successfully and cosmetically satisfactorily corrected. I have taken more than a little solace in the knowledge that should a crack happen and been sorted out my (an) instrument is actually better off and more stable than it was previously when the 'crack' was waiting to happen. It is a bit like the adage 'Whatever does not kill you makes you stronger' and but another example for the musician to heed.

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The tips and comments above are the result of many years of providing help and advice, my personal interest and study, and the teaching that I have done during my career. I have many colleagues and teachers to thank for sharing their thoughts and suggestions on this and other topics. In addition I am indebted to Woodwind & Reed, Cambridge ( www.wwr.co.uk ) where, in the course of helping customers, many of these concepts have been refined and have proven helpful.
Thomas Dryer-Beers