Anatomy of a Clarinet Crack Repair


Recently, we launched one of 2 new sites for our company focussing on the repair side of our company. The first, is www.ClarinetRepairs.com and the other www.SaxophoneRepairs.com. As we post new features on these sites, I might borrow some of the content for my blog because they are things that many players might find interesting.

One of the biggest fears for a clarinetist is of their wood clarinet cracking. Sadly, you can’t predict whether the clarinet will crack or not. You can be the most meticulous player who breaks in their clarinet and oils it regularly and still the clarinet can crack. You can be one of the most abusive players who never maintains their clarinet and it doesn’t crack. There is no rhyme or reason behind it.

As a player, you can help limit the chances of your clarinet cracking. For information on proper care & “break-in” on a new clarinet, download our “Wood Care & Preservation Guide” by clicking here.

So the question is, what happens if your clarinet cracks?

Crack repairs are not a simple thing to do well. There are many ways to “repair” a cracked clarinet, but many of them negatively effect the performance, appearance and value of your clarinet. When performed properly, your clarinet will play exactly like it did prior to the crack and there is little to no cosmetic blemish to your instrument.

Here at ClarinetRepairs.com, we are more then properly equipped to handle even the worst crack repairs. They say that pictures are worth a thousand words… so below, we present to you the step by step photo process of how we handle crack repairs.

The Crack

Why do clarinets crack? Sadly, there are several reasons why a clarinet can crack. Wood is hygroscopic. This means that it can absorb and release moisture. If your clarinet absorbs this moisture unevenly (perhaps through not properly breaking in your clarinet when it was new or when picking it back up after a period of not using it), this can create a stress pressure that builds up in the wood and just like an earthquake, that pressure has to be released.

With this clarinet, the student had not properly broken the instrument in when it was new and as a result, it cracked within 2 months. The instrument in question is a Leblanc but that has no bearing on whether it can crack.

As you can see, the crack is a wide crack that goes through 3 total tone holes (you can click the photo for a much larger version). This is no simple job. Before we can perform this repair, we clean the crack and joint to ensure that there is nothing that interferes with sealing the crack. We also will let the joint sit and dry slightly as the crack will close a little before we perform the repair.

Tone Hole Inserts

When the crack goes through the tone hole, the only way to bring back it’s integrity is with custom tone hole inserts. The original tone hole is cut out down to about 50% of the body. This leave the original undercutting shape in tact so that the performance of the clarinet when done is not affected by the insert. Depending on the severity of the crack, the tone hole inserts can be done before the full repair of the crack. This ensures a nice tight fit of the insert as was done on this clarinet.

As you can see in the photo, the top trill key tone hole has the insert installed and the next tone hole is bored out ready for it’s insert to be installed. We custom make each tone hole insert from hard rubber in our shop. The hard rubber gives a material that is easily machined so that we can ensure the tone hole is made and fit well and also gives a material that has a weight very similar to wood so that tone is not affected.

Pinning and Sealing

To properly seal the crack, we use a technique called “pinning”. We insert metal pins into the body of the clarinet. These pins are carefully placed so that they do not enter the bore of the instrument. These pins will force the wood back together in to its original position. This ensures that the inner bore shape of the clarinet is restored and the performance of the clarinet will be returned to its original design.

After the pins are inserted, the crack is sealed. The pin holes are then covered with Grenadilla dust and a Cyanoacrylate adhesive.

While this might look ugly now, all evidence of this work will disappear when we are all done with the repair. This pinning technique ensures that the crack will never re-open and will not leak.

Cosmetic Restoration

 

Now that the crack has been sealed and repaired, we then finish the job addressing the cosmetics of the instrument. The first step lightly sands the entire area to remove the excess buildup of the pin covers as well as the glue on the crack. As you can see, the evidence of the crack repair quickly blends away.

Next we refinish the body to give the entire clarinet the same cosmetic appearance. As you can see, other than the tone hole inserts and the glue remaining on the tenon (which will be covered by the new cork), the crack has basically disappeared.

The Finished Product

When all is said and done, our method of crack repair restores the shape of the bore thus restoring its performance, structurally stabilizes the instrument and cosmetically eliminates 99% of the evidence that the clarinet was ever cracked in the first place.

This particular crack repair would cost on average $170 as this was a very bad crack that needed 5 pins and 3 new tone holes. Most cracks are not as severe and can be repaired in the $60-$100 range. Our crack repair process takes on average 3-6 days depending on the severity of the crack.

If you have a crack repair that you would like performed by us, please give us a call.