 The Clarinet BBoard
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Author: nellsonic
Date: 2024-12-14 23:09
Attachment: IMG_7229.jpg (1375k)
A crack that was supposedly just pinned shouldn't be opening up again at all, especially after just a few weeks, right? This is my student's instrument. I am not a tech but it was sent to one who claimed he would pin it. I think it was just glued and it seems to me that it clearly needed more than that. Yes?
(image attached)
Anders
Post Edited (2024-12-14 23:14)
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Author: m1964
Date: 2024-12-14 23:49
I see what looks like one pin. If it was just pin it was not enough to keep the crack from opening.
Did they placed a bushing into the lower thrill key tone hole?
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Author: Julian ibiza
Date: 2024-12-15 00:21
That's quite a crack and it may be difficult to arrest its movement. It looks like it's been pinned ( I can see where the hole for the pin has been filled). Probably not a very good job and I think it's going to have to be done really well if it's not going to open. Unfortunately this crack will make the trill key chimneys leak.
Julian Griffiths
Tel. 34 696 798 853
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Author: clarnibass
Date: 2024-12-15 10:11
No, it's just not possible to know for sure or 100% control a crack and it could re-open or not after repairs, even if it's glued, pinned and banned. Cracks vary in how much they "try" to open and re-open.
For example two cracks that look similar, both are (e.g.) 1mm wide, one might already be at its limit, the other might still have an enormous amount of force and try to open to 1.5mm.
Some cracks can be fine without any repairs. I have one customer with a clarinet that cracked about 40 years ago... it was glued (not by me)... obviously re-opened slightly since then (also a very long time ago)... and it's been fine since then with no repairs.
In contrast, I had a bass clarinet with several bad cracks, and no matter how many pins, bands and glue I used, it still re-opened slightly every once in a while (it's not common, it was the worst cracked clarinet I've seen).
So you can't expect a crack to absolutely not open after a repair, but better to explain it before. There are all sorts of things you can do to prevent a crack from re-opening as much as possible, but it's not really guaranteed (assuming one of the standard methods like gluing, pinning or banding).
There is what looks like one pin hole in that photo. There are also some sanding marks near that same area. That doesn't mean there aren't more pins, and it doesn't mean that even six more pins would completely prevent it from re-opening.
Pinning (and repairing in general) in the most relaxed state can help, but it's not possible to say whether this was done or not (it can change over time, especially if it cracked recently, it might still try to find its way to that state).
Post Edited (2024-12-16 09:15)
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Author: Julian ibiza
Date: 2024-12-15 13:27
I would be inclined to describe that crack as one with the laws of physics very much on its side, so as Clarnibass says, I wouldn't be too hard on whoever attempts to repair it. Ideally they should first point out that there are can be no guarantees however, so that everybody knows where they stand.
Julian Griffiths
Tel. 34 696 798 853
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Author: Chris P
Date: 2024-12-15 15:02
Whoever did that was indeed pinning all their hopes on that one pin to fix an extensive crack that potentially runs all the way from the tenon shoulder right down to the thumb ring pillar following the grain, so it was destined to fail.
Chances are they pinned it when the crack had closed up again which is what they often do on their own accord, but will reopen as soon as you start introducing moisture to the bore and the stress forces the surface crack to reopen.
I've found it best to fill the cracks in while they're still evident, then both carbon fibre band around the entire circumference of the joint and pin in the least accessible areas where banding isn't possible due to pillars and toneholes being in the way.
A poorly repaired crack will always fail regardless of the method used if it's been done at the wrong time. Catch the crack early as you can to repair it or if that's not possible, then force the crack to reopen again by introducing both moisture and heat from the inside.
Anyone saying "cracks are always a straight line" are idiots - I don't care who they are, they're still idiots and they need to shut the eff up. Cracks will follow whatever line of weakness there is and that's the line of the grain which is rarely ever a straight line as you can clearly see in the photo.
http://test.woodwind.org/clarinet/BBoard/download.html/1,8448/IMG_7229.jpg
Even a repaired crack done well doesn't mean another crack won't happen elsewhere on the same joint. Wood is a live substance and will change according to humidity changes. Right now in the northern hemisphere with low humidity levels and then suddenly introducing humidity to the bore, this is where wooden instruments are at the mercy of everything that can possibly destroy them.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
Post Edited (2024-12-15 15:07)
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Author: kdk
Date: 2024-12-15 18:36
I had a clarinet (my first R13) once with a crack similar to this one that went through a trill key's tone hole. A repairer flush-banded it with some kind of metal (probably steel) bands. I was too young to tell if he also pinned it. He told me (back in the 1960s) that there wasn't much he could do where it went through the tone hole. Now, 60 years later, I wonder if it's possible/practical to bore out the tone hole itself and glue in a new (probably hard rubber) chimney or a sleeve to replace the cracked pad seat. I think I've read comments here suggesting that that's possible.
Karl
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Author: RBlack
Date: 2024-12-15 20:42
Totally possible to put in a tonehole insert!
Some techs tend to not do it, not sure if it’s lack of the tools, or too busy and not wanting to take the necessary time. Ideally you’d want someone who has done it before, rather than someone who doesn’t normally do it and lacks the experience with the process. It is a little bit scary to do the drilling out of the TH part, but imo drilling holes for pins is more anxiety inducing.
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Author: m1964
Date: 2024-12-15 21:11
I once had a clarinet where the crack went through a tone hole- my tech fixed it by placing seven pins and the tone hole insert.
He said that there was (sort of) a rule of two pins for every inch of a crack.
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Author: Chris P
Date: 2024-12-15 23:39
Tonehole bushing is the best course of action whenever a crack runs into or across a tonehole. The damaged tonehole is cut out and then bushed with either a plastic or an ebonite bush and should the crack reopen, it won't run across the crown and cause a leak where the pad seats against the tonehole and the crack can then be filled in.
Even if a crack goes right through to the bore, it's still fixable and if done well, it shouldn't impact on the playability of the instrument.
Even under guarantee, it's far better to have the crack repaired than replacing the entire top joint as that way the clarinet you chose is still the one you'll have once the crack has been repaired, as opposed to a top joint transplant which may not play the same way as it did with the original top joint. Plus the fact that scrapping a top joint is wasteful and more costly to the company that made the instrument.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
Post Edited (2024-12-15 23:45)
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Author: clarnibass
Date: 2024-12-16 09:44
>> Some techs tend to not do it, not sure if it’s lack of the tools, or too busy and not wanting to take the necessary time. <<
Sometimes it's neither. I've done it, have the tools and don't mind taking the time, but often don't do it. It's usually the clarinet owner's choice. Most here prefer to save the cost, time and "intrusiveness" of that repair unless it's absolutely necessary.
By sometimes not doing it, I statistically proved to myself that more often than not it's not necessary. I've seen inserts fail too.
In some cases I consider it necessary and only agree to do the repair if it includes an insert, but not most of the time.
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Author: Chris P
Date: 2024-12-16 14:55
It's always best to bush a tonehole with a crack running into or across it as you can't guarantee it won't reopen again if it's just been filled in. That's especially vital for top joint toneholes as that will be the difference between your clarinet playing well or not at all.
If your usual repairer doesn't or just refuses to bush cracked toneholes, then find another one that does. Any decent repairer should be able to bush toneholes in their sleep, especially if they specialise on oboes and cors as they often have cracks running across the trill toneholes or from the 3rd 8ve vent through both trills and into the LH1 tonehole.
The same can be said about any aspect of instrument repair - if your repairer can't or refuses to perform any relatively simple and routine task, find someone else who does and who can put their money where their mouth is instead of being all talk.
There's loads of different ways to achieve the same result - they can even be done freehand using the right types of cutters, pilots and a bench motor as well as a steady hand. Another way is using a pillar drill and another way is machining the bush to the correct profile and gluing it in. Typically they'd only be sunk into around 4mm into the joint which is as deep as cracks tend to go (joint walls are usually around 8mm thick), or to the depth where the undercutting starts.
As for carbon fibre banding, that will support the entire circumference of the joint rather than just holding the crack in one area. I've seen some brand new clarinets (Royal Global I think) are even made with pre-emptive carbon fibre bands on the top joint.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
Post Edited (2024-12-16 15:37)
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Author: donald
Date: 2024-12-16 15:49
My 1990s R13 had a crack that ran into the "side Bb" tonehole- and this was repaired initially with glue (Francois Kloc/Bufet) then when it opened again a tonehole insert/bushing was installed, and the instrument played well for a further 10 years.
When it was finally sold, the teacher who bought it from me (to on-sell to a student- but he also makes considerable income buying/selling used instruments) announced that "crack or no crack" it was the best R13 he'd ever played.
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