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Martin toneholes

Do you own a Martin sax?
If you're very, very quiet and you listen very, very hard you might just hear a faint ticking sound...
That's the sound of the Martin Tonehole Timebomb. Yep, the Martin's very own built-in genetic disorder...Selective Galvanic Corrosion.

What makes the Martin distinct from many other horns is the use of soldered-on tone holes. Most other makes use drawn tone holes, whereby the wall of the hole is pulled out of the body material.
For many years I'd always been puzzled as to why so many Martins came in with leaking tone holes. In most cases there wasn't any collateral damage (such as a dent adjacent to the affected tone holes) to explain the leak, and the only reasonable explanation was that the solder had broken down in some fashion. This supposition was borne out by examining the mating surfaces when the tone holes were removed...the part of the soldered joint that had failed was always a powdery grey colour, with the rest being bright and shiny...typical of a freshly soldered (or unsoldered) joint.
I'd always imagined that this degradation was caused by an initial fault in the joint, which subsequently allowed moisture to get in...which then oxidised the solder and slowly increased the size of the fault.

As it turns out I wasn't so far off the right track...the solder was being broken down, moisture had a lot to do with it - but the actual process is an electrochemical one. It's called Selective Galvanic Corrosion (SGC), and it describes how at the contact point of two dissimilar metals in the presence of moisture there will be an electrical difference. A battery, in other words.
There is a list of metals called the Galvanic Series, and essentially the further apart any two metals are on that list, the greater their propensity for succumbing to an electrolytic reaction.
Brass, which forms the body of a sax, and Lead, which forms the best part of soft solder, are quite far apart - and so they readily react when an electrolyte (water, in this case) is present. A tiny current is produced, and this is sustained by the conversion of the lead in the solder into an oxide. This is the powdery grey deposit where the leak forms.
There need be no initial fault in the joint - all that's needed is for the joint to get wet and it's away.
This phenomenon also goes some way to explaining why other soldered joints fail - such as the crook tenon (or, on trumpets etc., the tuning slide bow joints). What's perhaps rather more worrying is that some saxes have solid silver crooks...silver and lead are further apart in the galvanic series than brass and lead, so the potential (excuse pun) for corrosion is worse.

Manky Martin toneholeAs for how long the process takes, I don't know - but I've seen Martins from the early 1960's with the problem, so a fair bet would be at least a few decades...though that rather depends on what sort of life the horn leads. With many Martins touching 60 or more years these days you can imagine how many of them might be suffering right now.
This tonehole on the left is well on its way to dropping off.
The blue-green stuff is Verdigris (pronounced 'Ver-dee-gree') - a type of corrosion that affects copper-based metals. This in itself can be quite damaging - if left to its own devices it can result in pits in the underlying brass. It's a fair bet that if you find any of this stuff around your Martin toneholes then the solder will be on its way out.
Note the distinct crack on the lower edge of the tone hole - the solder here has been dissolved and a substantial leak has been created. There's no way back for this tonehole, it will have to be removed, cleaned and resoldered. The effects are quite serious for the player - an affected tone hole can be responsible for quite an appreciable leak, and if there's more than one you could be in quite a bit of trouble when it comes to those low notes.
Spotting the leaks can be a little difficult. If you hold the horn up against a bright light you may be able to see chinks of light shining through the gaps (you could use a leak light, if you have one). In some cases though, and for a variety of reasons, the leaks won't show up with this method - and another method I use is to physically test the tone holes by pushing at them with a finger.

By far the most definitive method is to drizzle a little cigarette lighter fluid around the outside of the tone hole (it won't damage the horn's finish) - if you spot any ingress into the bore then you've found a leak. Water won't do the job, the surface tension will prevent it from seeping through a small gap.
It's quite a tricky job with all the keys fitted, but it's just about doable. If you can remove the keys, even a few of them, it makes things a great deal easier. It also allows you to carry out the 'sniff test'. Cigarette lighter fluid has a distinctive odour - if you sloosh some around the outside of a tonehole and then run your finger around the inside, you might well not see any fluid on it...but if you give it a sniff you may find that a tiny amount of fluid has leaked through.

Martin low C toneholeOf course, the very fact that the tone holes are soldered on means that they can be unsoldered and refitted.
This is the proper method of fixing the problem.
It's not a cheap job to have leaky tone holes fixed - there are no shortcuts.
You can't just try to resolder the leaking portion, the whole tone hole has to be removed and the mating surfaces properly cleaned before you can be assured of a decent new joint. Any attempt to fill just the leaking portion runs into the problem of the joint being heavily contaminated with a substance that new solder just won't adhere to.
On the right is superb example of this; the photo shows the mating surfaces of a low C tonehole and its corresponding tonehole ring where an attempt has been made to correct a corrosion leak without removing the tonehole. The bright areas indicate where the solder has mated and made a good joint - the dull areas are where the solder had been eaten away and all that's left is a dry, cruddy area that will never take fresh solder in its present state.
Oh, I've tried...believe me I've tried - but no matter how thoroughly you try to clean the hole out you can never ensure a clean you end up forcing ever more soldering flux into the breach in the vain hope that it will remove the oxides and allow a new joint to take.
This makes a dreadful mess around the tone hole, and the usual result is an unsightly wall of solder that doesn't so much penetrate the hole as simply covers it over - as can be seen in the example below.

Martin bari toneholeSome people are happy to leave it at that - but anyone with any pride in their work will admit defeat and remove the entire tone hole...and never make the same mistake again.
If you see a Martin with piles of solder around the tone holes you'll know that there's a very good chance that there's a gap underneath...and that gap will be letting moisture right into the joint...and the tone hole time bomb will be ticking merrily away...

Incidentally, if you look at the above photo of the low C tonehole you can see that there's an area of solder that runs onto the body of the horn off the bottom of the tonehole. Now note the unmarked area to the right of the tonehole. What this tells you is that solder (and heat) has been applied to one area only - and more importantly that it hasn't been applied all the way round (you will nearly always lose the lacquer when resoldering toneholes). This is a dead giveaway for a botched corrosion job - and it will almost always mean you'll have to cough up for a proper repair.

Once the tone hole is off the body the mating surfaces can be properly cleaned and repaired and the tone hole refitted neatly.
The drawback of course is that this does nothing for the finish. It's not so bad if all the lacquer fell of years ago, or the horn is silver plated (though not with a sandblasted/matt finish..the pits fill with solder, very difficult to remove), because no matter how careful you are with a gas gun you're certain to take out some of the finish simply by virtue of the amount of heat needed to get such a large surface area up to soldering temperature (not to mention the cleaning up and polishing).

I said there were no shortcuts, and there aren't for a proper job, but there is a little trick that can get you out of trouble...though if you're a purist, look away now.
Superglue is the answer. In fact, superglue is so suspiciously perfect for the job that I often wonder whether the inventor didn't have half a dozen Handcrafts knocking about.

I'm pretty sure I'll get a lot of flak from various quarters for even suggesting this fix - but then if you're the proud owner of a mint Handcraft and you're staring at a potential bill of £40+ and the prospect of a damaged finish for the sake of addressing a small leak, the offer of a £5 fix that will work without trashing the horn's cosmetic integrity is, to my mind, a viable option.

Martin low D toneholeIt's really only a suitable fix where the length of a tone hole gap is no larger than a quarter of the diameter of the tone hole, and it's important that the hole is glued without any pressure being applied to it as the glue cannot be relied upon to hold against the constant stress of the tone hole trying to get back to its resting position (so if your gap is much thicker than a cigarette paper you'd be better off having the proper job done).
Ideally the glue should be applied from inside the tone hole - but this will mean removing keys, which isn't always easy.
Providing you're careful, a decent enough fix can be made by tackling the outside of the tone hole.
The tonehole pictured on the right is a perfect candidate for this fix. The horn has been finished in black lacquer, which the owner is quite keen not to have damaged. The gap in the rear of the tonehole joint is relatively small and covers barely an eighth of the diameter of the tonehole itself. Incidentally, this Martin had five affected toneholes plus a further four that had previously been patched up.

Where I use this method I do so in up to two stages depending on the size of the gap.
First though I clean the gap. For this I use lighter fluid. This will drive out any water or oil in the gap. It can take up to half an hour for the lighter fluid to fully evaporate from inside the gap. A little heat from a lamp or hairdryer will assist - don't use a naked flame.
If the gap is tiny, a hairline crack even, then I would use a standard 'liquid' superglue. For a neat and controllable job it's best to use a needle - apply a small droplet of glue to it, then apply the needle to the gap in the joint. All being well the glue should flow right into the joint nice and tidily.
It obviously makes sense to position the horn so that any glue applied will flow into the gap, and along it - and that position should be held for as long as it takes for the glue to stiffen.
For a slightly larger gap I use the liquid glue first (allowing it to set), then follow it up with the gel type glue. This has better filling properties, though it will not flow into the joint.
You can't easily apply it with the needle, so you'll have to rely on a steady hand and a clean nozzle on the glue tube.
The gel type glue sets a great deal slower than the liquid type, so if you make a pig's ear of the job you might have half a chance of cleaning it up. I would recommend allowing a good few hours for the glue to set completely before using the horn.
If there is a problem with this fix it's that the corrosion seems to take place most commonly at the rear of the tone hole - which can make it tricky to gain access if you're not prepared or able to remove a few keys.
When you're buying your superglue, pick up a tube of superglue remover at the same time - just in case of accidents and spills. In the event of a dribble of glue getting where you don't want it, mop it up as quickly as you can, smear the area with the remover and then gently mop it off. Works a treat.

The big plus with this fix is that it avoids the inevitable damage to the finish that resoldering a tone hole causes (though do bear in mind that you still run the risk of damaging the finish if you manage to get excess glue on it)....and if you do a neat enough job no-one will be any the wiser, and there's every chance the repair will long outlast you.
If the idea of superglue troubles you, you can use clear nail varnish for a less permanent fix...or even warm wax.
Whatever you do, don't be tempted to use an epoxy adhesive. Good though these glues are they rarely have the flow characteristics of a liquid glue and so won't seep into the joint, and they're far harder to remove when the time comes for the tone hole to be properly fixed.

Martin Committee III baritone top bowHere's an excellent example of a corroded joint that's been given the superglue treatment.
There are three distinct areas visible on the joint face; to the right you can see viable solder - the slightly bright, silvery sheen indicates that this portion of the joint was in good order. In the middle you can see the dull grey, slightly powdery section that's indicative of the solder having been broken down - and this section of the joint would have been leaking. To the left the white deposit is the remains of superglue - this is what it looks like after it's been heated during the desoldering operation. Someone's clearly detected a leak and sought to repair it with superglue. I don't blame them - this is the lower section of the top bow on a baritone, and to fix the joint properly requires extensive and expensive dismantling of the horn. The tube is well supported by two braces (so it's not going anywhere), and with at least some of the joint being in good order it made sense to give the superglue fix a go...and wait until the horn required a proper service before dealing with the corrosion. However, as you can see, they didn't quite seal all the leaks.

This is a good example of how SGC can affect any horn - and as it happens, this too is a Martin (a Committee III)...and the irony is that although this joint has been badly corroded, none of the toneholes had. Typical.

As for prevention, probably the best thing you can do is to ensure you thoroughly dry the bore of the horn after playing. It's no wonder that old Martins in excellent condition, due to their not having seen much use, tend not to have the problem...and the old faithful jobbing horns that have been played day and night for decades can be riddled with leaky tones holes.
It would be impractical to treat the joints with a protective coating (though not impossible) such as lacquer, and I'd be inclined to consider a dual-cleaning regime using a pull-through first followed by a pad saver. I would also remove the pad saver afterwards because its slow-drying action wouldn't be an advantage in this case. This should ensure very little moisture is left hanging on in the tone holes...and to be really sure it would be a safe bet to let the horn air for an hour or so before putting it away.

So how worried should you be about this potential problem?
Since this article was first published in 2006 I've seen a wide range of reactions to it. Some people take the worst point of view and decide that they've never going to buy a Martin saxophone - which is a great shame as they're one of the best vintage marques out there. At the opposite end of the spectrum there are those who insist that it's not a problem and that they've never encountered it. The laws of physics dictate that it's a problem, and on this page alone there are four individual Martins that are suffering with it. I've seen quite a few more - which was what prompted this article.
And I'll be frank. It can be difficult to spot tonehole joint leaks, and the only way to be 100% sure is to strip the horn down and get busy with the lighter fluid. If this test hasn't been done you cannot know what state the toneholes are in. Claims of having owned x number of Martins that have never had this problem are meaningless unless this test has been carried out on each of them.

I would advise taking the middle ground. Be aware of the problem and learn how to spot it. If you're buying a Martin take the time to carefully examine the tone holes - and maybe try the lighter fluid test. Don't be put off if you find a problem - just negotiate the asking price down to take into account of the cost of repairs (assume around £40 for a single tone hole, £20 for each extra one - and something on top for loss of finish). If you own a Martin and find it has the problem, take it to your tech and have it fixed - or, if you feel confident enough, try the home workshop fix where appropriate.

Copyright © Stephen Howard Woodwind 2015