 The Clarinet BBoard
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Author: Ben Shaffer
Date: 2014-07-20 17:18
Well several weeks ago after a session of playing my Wood Normandy 4 I was dismayed to discover a crack about 2 inches long on the top part of the top section. ( left hand section for me)
The " Crack" did not go all the way through to the inside of the bore, so technically I believe its called a check
I took it down to my local repair Guy and he filled it in with a glue and wood powder concoction of some sort.
When I picked up the Horn after the repair you could not even see where the crack had been...except where the repair went through the logo
Anyhow , I went home played the Horn for a few days and the crack opened up again and now extended as far as the tenon, where previously it had only gone about an inch below the tenon
I took it back to my repair guy, who was surprised.
He is now going to create a carbon Fiber band around the tenon........ if I understand him correctly.
He says this should take care of things.
Can anyone tell me about this repair method?
Post Edited (2014-07-20 17:21)
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Author: Chris P
Date: 2014-07-20 19:22
Merely filling in a crack won't stabilise it, so it's very likely to open up again or spread further than before.
Having it carbon fibre banded or pinned will add stability and reduce the chances of it opening up again.
Search 'carbon fibre banding' and you should find more info - if it goes through the logo, then that's a shame, but it's a cosmetic sacrifice.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
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Author: Bruno
Date: 2014-07-20 20:43
If you think that your "repair guy" should have suggested pinning and banding your clarinet in the first place, as I do, it might be wise to ask a different repair person to evaluate it.
Seems to me he should have known that filling the crack wouldn't be adequate.
bruno>
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Author: clarnibass
Date: 2014-07-20 21:20
>> Seems to me he should have known that filling the crack wouldn't be adequate. <<
I sometimes do carbon fiber banding and pin cracks too so I'm not against doing that. Some cracks are completely stable with just glue. Some cracks will actually never get worse by doing nothing. Unfortunately it is never possible to know that, since the size of the crack means nothing to how it is going to behave later.
A big crack that is not leaking or causing a leak might stay exactly the same forever, while a crack that starts tiny might grow fast or very slowly and create all sorts of problem. Or any other possibility.
How do you suggest the repairer could have known whether filling the crack would adequatre or not...?
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Author: cyclopathic
Date: 2014-07-20 21:47
@ Bruno
that does not mean anything. I have glued cracks which didn't come apart and glued old pinned ones which had opened up. It depends on stability of specific piece of wood, and if you wanna minimize cracking restoring it with bore oil and keeping out of extreme temps helps, but it is never 100% proof, YMMV
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Author: Bruno
Date: 2014-07-21 07:37
From what the OP said, and this answer by a poster, "Merely filling in a crack won't stabilise it, so it's very likely to open up again or spread further than before." . . . .
I just thought that it was what happened to most cracks. My mistake - sorry.
bruno>
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Author: clarnibass
Date: 2014-07-21 12:38
>> this answer by a poster, "Merely filling in a crack won't stabilise it, so it's very likely to open up again or spread further than before." <<
In some cases, the wood is stable after cracking without anything done to it. If glued, the crack will be as stable as it was going to be anyway. I just saw a clarinet with a 40 years old crack that was never repaired and no issues as a result at all (no leaks and not getting bigger).
Sometimes the force trying to re-open or enlarge a crack is not more than the force of the glue holding it, so the glue is enough to stabilise it. This also depends on the type of glue, how it was applied, etc.
Pinning and banding repairs are done more as a safety, not always necessary, just because statistically some cracks do open after less intrusive repairs.
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Author: Chris P
Date: 2014-07-21 14:37
If the crack has been allowed to close up a bit since it split and is then filled, it's more likely to open up. If the crack is fresh and filled immediately, it will be in compression and may not open up afterwards.
These are all possibilities - cracks can happen at any point in time, so the risk is always present. Sometimes another crack can open up somewhere else once an existing one has been filled in, so expect the unexpected.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
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