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How to work in a tone chamber

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I've got a couple of questions about working in/around tone chambers. I generally avoid work associated with them, unless it’s spot tuning and minor maintenance. I don’t seem them very often, which is a good thing.
I recently fixed some leaky pallets within the chamber, but I find it difficult and (tbh) easier just to decline the work.
Tuning... with a double tone chamber, the two reed blocks are set sideways on, tucked one in front of the other. What is the technique to tune them, other than pulling them out, making adjustments and returning to the chamber? Obvs you can’t get at the reeds at all (except the very front row).
Fixing or even replacing pallet facings, I was recently asked about refacing pallets, which included the levers tucked inside the tone chamber. Previously I had successfully relaminated some leather facings that had come adrift, within a tone chamber (l have done this job a few times...but it is horrible). The key levers were not the sort that are individually removable, so I had to pull the axle/spindle in and out (about 4 times in the end, to test the repair for air tightness). So what is the technique for refacing tone chamber pallets and setting the pallet flat, if you happen to remove the pallet? You can’t get into the chamber to apply wax or glue and it all needs to be exactly correct, the levers (that I have seen) have two pallets, one in the tone chamber and one sitting at 90degrees on the fondo, where you can see it. If you are threading the lever onto an axle to get it back into the chamber, you can’t re-fix the pallet flat until its in the chamber, but once it’s in there, you can’t get at it. I assume there are special toolS...or is this something only possible during factory construction, where they probably do it on a jig?
 

Dingo40

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Roger,
It sounds like a nightmare!
I totally empathise with your comment: sometimes it's better not to become involved and to just leave it well alone!🙂
 
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debra

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If I were to decline repair (and tuning) jobs on accordions with cassotto I would lead a very quiet life. About 90% of what I do is accordions with cassotto. The worst possible things to do when working on accordions are 1) trying shortcuts and 2) rushing a job.
When I tune an accordion I first sit down, play and measure each note with each reed separately and write a list with all the deviations from the "standard" frequency. Then I take out all the reed blocks and do a "guestimate" tuning, trying hard to not overshoot (when a note is too low I will raise the pitch, but not to the point where it's now too high). Then I put everything back together and measure again. (I tend to not do it on all reed blocks at once, but the principle is the same.) I repeat the process once or twice until the measurements are close. Then I start fine tuning in LM, MM and MH registers, making sure all of these sound right on all notes. (A reed may be tuned slightly differently when it is played alone versus together with a different reed, so L alone may differ from that L reed in LM register for instance.)
It's actually a fairly efficient process, it works in cassotto the same as outside the cassotto, and it does not involve fiddling with reeds in the very narrow space between reed blocks. Of course for some final smaller adjustments I will work on the reeds inside the accordion (unless it's in cassotto).
Likewise, if you need to do something precarious like work on a pallet inside the cassotto, take the key out. And yes this probably involves first removing the register switch assembly, then pulling out the rod partways and removing all keys up to the one you need to work on. Nobody ever said that accordion repair was easy and/or quick. And this explains why (unless you get a volunteering trained non-professional like me to do it) repairs are always more expensive than you anticipate. The "it's just one key" idea is a fallacy, just like "only a few notes are out of tune". I always either tune a complete accordion or I do not tune it at all. (The one exception is when tuning one of my own accordions, because they are always tuned and I fix a single reed the moment I hear it is out of tune. I do not wait 30 years like many people do...)
 
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Thanks Paul. Good reply. I imagine the cassotto levers must have their pallets fixed in the factory on a jig.
If the keys are mounted on a key way it makes things just a little bit easier, because they can be taken off individuall.
I guess if I kept getting cassotto instruments I’d have to get used to it. But it isn’t that common here in the UK.
 

debra

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Thanks Paul. Good reply. I imagine the cassotto levers must have their pallets fixed in the factory on a jig.
If the keys are mounted on a key way it makes things just a little bit easier, because they can be taken off individuall.
I guess if I kept getting cassotto instruments I’d have to get used to it. But it isn’t that common here in the UK.
There are several different keyboard mechanisms that do not use a long rod as axle which the key mechanism rotates around. On these you can remove individual keys in the middle. But the most common mechanism used today is the one with one or more axle-rods.
When building keyboards in the factory they do have a jig for the right angle between the cassotto and non-cassotto part, but the arms for each key are bent individually with pliers to make them fit perfectly. It is different for each note, so you need an expert who can do this quickly and perfectly. (I have seen one do it in the factory. Amazing!) As part of training I have done just one key, without cassotto. That took long enough, but it did make the general idea very clear. (Same with bass pistons, by the way.)
 

boxplayer4000

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I agree. A nightmare, mostly, to deal with.
I sympathise with Roger in declining work. I worked with a high profile recording artist who’s cassottoed pallets were in need of attention (an air leak resulting in the reed sounding when the note was NOT being pressed). The final straw in refusing the work was that the midi key contact strip, which was blinding the access, was installed in such a way that a mass de-soldering job was required.
Roger touches on the subject of adjustment of the two pallets serving the one note, one inside the cassotto and one outside. If one of those are out of adjustment by as much as the thickness of a piece of paper air leakage will occur. Three parameters need to be met when adjusting; namely the two pallets but also the height of the key top (which needs to be level with the other keys). Since the pallet inside the cassotto is not accessible then the adjustments can only made at the other two components.
Can somebody please remind me of the maker of the cassotto system whereby the two pallets are not ‘fixed’ but one is hinged with a spring so that the pallets are always in adjustment?
 

Ventura

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i re-padded my Gola once, many years ago, after trying first to deal with 3 errant chambered valves..
fuggedaboutit
was way easier to just do them ALL at once and the same, in chamber and out, new pads were all
the same thickness so really only a tiny bit of finesse leveling was needed

i will say that on an older accordion (pre articulating pallets era) i would run away
as fast as i could... a flexibly mounted pallet can seat itself at the correct angle

you would have to have the patience of Jobe ( or Debra ) to work on a waxed pallet
tone chambered model !!! and a very delicate touch

ciao

Ventura
 

debra

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i re-padded my Gola once, many years ago, after trying first to deal with 3 errant chambered valves..
fuggedaboutit
was way easier to just do them ALL at once and the same, in chamber and out, new pads were all
the same thickness so really only a tiny bit of finesse leveling was needed

i will say that on an older accordion (pre articulating pallets era) i would run away
as fast as i could... a flexibly mounted pallet can seat itself at the correct angle

you would have to have the patience of Jobe ( or Debra ) to work on a waxed pallet
tone chambered model !!! and a very delicate touch

ciao

Ventura
When you have a "wheezer" (a note sounding while not being pressed) you can adjust the arms (inside cassotto or outside) by using the proper tools, which are called "torciferri". They are indispensable for an accordion repairer. But sometimes you can do small corrections on a "wheezer" with waxed pallets by softening the wax (not completely melting as it will run) and correcting the position. Basically what you do is put a piece of cardboard with a cutout over the pallets (cutout over the one you need to adjust) and then you heat up the wax with a hairdryer. You can only do this on the pallet outside the cassotto this way. For the one in cassotto you do need the right torciferri.
 

NickC

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I have zero knowledge of tuning accordions, but can the reeds be tuned outside of the instrument on a 'tuning table.'? Or did I just now make up the word 'tuning table'?
 

boxplayer4000

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Debra
The key bending tools I have (all home-made from mother-in-laws clothes drier which was made from chromed steel) are all simple, straight tools.
I suspect your 'torciferri' might be variation of these. Would it be possible for you to describe them or better still post a photo please?
 

TomBR

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I have zero knowledge of tuning accordions, but can the reeds be tuned outside of the instrument on a 'tuning table.'? Or did I just now make up the word 'tuning table'?
Yes a tuning table is a piece of equipment for tuning reeds.
Reeds can be tuned outside of the instrument, but only approximately, the pitch is likely to be affected when they are reinstalled so fine tuning has to be done in the instrument.
 

NickC

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Thanks for the clarification, Tom. I thought I heard that term before. It makes sense though that they would have to be fine tuned afterwards, and even tuned against the other reeds.
 

Dingo40

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Boxplayer,
This website may be relevant?🤔

 
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I also have a selection of bending levers, some bought from Carini (the Italian parts supplier) and some home made. The problem, however, is that any lever height adjustment alters the angle of the face of the pallet. It’s generally not possible to get an airtight pallet, one that is perfectly flat against the fondo, by putting tiny bends in the lever (not side to side, which is different...although I’m not sure if I’ve seen a tool which can actually do this ... it grips the pallet end in place and only applies the bend to the key side...maybe i imagined it). You will always get an air leak. Anyway, If the pallet is floating it is self levelling, so there is no problem (e.g. it is mounted on a rubber hinge). If it is fixed, the technique is to alter the lever by bending it, then releasing the glue/wax so that the pallet sits exactly flat, and reglue/wax. Obvs you can’t do this inside the tone chamber/cassotto, which was the reason for my OP. As mentioned, I think the manufacturers might use a jig to mount the cassotto based pallets in the right place, and then assemble them on the accordion. Or they use some other technique, again back to my OP. Softening the wax with a hairdryer is obvs one way to go. Debra describes this. I perhaps ought to get hold of an old cassotto accordion to perfect the technique. I am intrigued now and kind of want to find a good solution...
 

debra

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I also have a selection of bending levers, some bought from Carini (the Italian parts supplier) and some home made. The problem, however, is that any lever height adjustment alters the angle of the face of the pallet. It’s generally not possible to get an airtight pallet, one that is perfectly flat against the fondo, by putting tiny bends in the lever (not side to side, which is different...although I’m not sure if I’ve seen a tool which can actually do this ... it grips the pallet end in place and only applies the bend to the key side...maybe i imagined it). You will always get an air leak. Anyway, If the pallet is floating it is self levelling, so there is no problem (e.g. it is mounted on a rubber hinge). If it is fixed, the technique is to alter the lever by bending it, then releasing the glue/wax so that the pallet sits exactly flat, and reglue/wax. Obvs you can’t do this inside the tone chamber/cassotto, which was the reason for my OP. As mentioned, I think the manufacturers might use a jig to mount the cassotto based pallets in the right place, and then assemble them on the accordion. Or they use some other technique, again back to my OP. Softening the wax with a hairdryer is obvs one way to go. Debra describes this. I perhaps ought to get hold of an old cassotto accordion to perfect the technique. I am intrigued now and kind of want to find a good solution...
The ones I have are also from Carini. For those who have no idea what they look like, here is a picture from their website.
99501-01.jpg
Typically when you have a "wheezer" it's one reed that is sounding, indicating the pallet is already at the wrong angle. So when you twist the arm in the right direction you are correcting the angle. But, when the whole pallet is too high for instance you can bend it so it gets "closer", and then use the hairdryier method to soften the wax and bring the pallet into alignment. It's all a bit delicate, but sometimes necessary. I once had to do it on a brand new Bugari (289/ARS/C4) conservatory, cassotto model with a wheezing H reed. The hairdryer method was all that was needed to fix the problem. But what is more common is that people have a shoulder strap catch on a key of one of the high notes, bending the key out of shape (sticking up) by 1/4" or so and then rather than brute force on key and lever it's best to use a torciferri to correct the problem.
 

boxplayer4000

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Dingo40,
I missed that picture of the 'cassotto' bending iron on the Hohner website. Thanks. A normal bending iron is a simple straight tool but of course there needs to be a bend on it for a cossotto situation.
Nobody has come back on my earlier mention of the cossotto design where one of the pallet levers was hinged with a spring. This allowed perfect automatic adjustment of the pallets and only the key height was left to be adjusted. Have I just dreamt this concept or should I be contacting the patents office now?
 
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I haven’t seen the hinged lever design, but it would be good to come across it. Some of the problem of air leakage could be alleviated by having floating pallets, though they need more room to accommodate the rubber hinge, so perhaps there isn’t room inside the cassotto?
 
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