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Tuning an old instrument to 440


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Here is what an overhaul of a vintage instrument can look like

 

 

The concertina is a model 21, 48-key treble, manufactured in London by Wheatstone in 1927. It has flat metal ends, metal buttons, and a newer 6-fold bellows. Most of the parts, besides the bellows and thumb straps, appear to be original. The concertina is in "old pitch", and is approximately 55 cents sharp of A440. There are numerous, small cracks in both pad pans, which have been "finished" by a previous repairperson, possibly in an attempt to fill these cracks.

Recommendations:

1) Fill the pad pan cracks with glue to eliminate air leaks. This will involve removing and replacing approximately 12 pads.
2) Replace the valves.
3) Replace the thumb straps. This is, perhaps, optional if you don't find them objectionable; I find them uncomfortably stiff.
4) Shim the bellows frame gaskets to eliminate leaks between the reed chambers.
5) Shim the reeds as necessary to fit snugly in the reed pan.
6) Add solder to the tips of the reeds to bring the pitch down and tune to A440. I believe we discussed this on the phone. It is more time consuming to tune this way, but it eliminates the risk of damaging the reeds by over-filing.

 

Edited by Everett
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13 hours ago, Everett said:

Here is what an overhaul of a vintage instrument can look like

 

 

The concertina is a model 21, 48-key treble, manufactured in London by Wheatstone in 1927. It has flat metal ends, metal buttons, and a newer 6-fold bellows. Most of the parts, besides the bellows and thumb straps, appear to be original. The concertina is in "old pitch", and is approximately 55 cents sharp of A440. There are numerous, small cracks in both pad pans, which have been "finished" by a previous repairperson, possibly in an attempt to fill these cracks.

Recommendations:

1) Fill the pad pan cracks with glue to eliminate air leaks. This will involve removing and replacing approximately 12 pads.
2) Replace the valves.
3) Replace the thumb straps. This is, perhaps, optional if you don't find them objectionable; I find them uncomfortably stiff.
4) Shim the bellows frame gaskets to eliminate leaks between the reed chambers.
5) Shim the reeds as necessary to fit snugly in the reed pan.
6) Add solder to the tips of the reeds to bring the pitch down and tune to A440. I believe we discussed this on the phone. It is more time consuming to tune this way, but it eliminates the risk of damaging the reeds by over-filing.

 

 

I have to say Everett, that your experience of this instrument is unfortunate in some ways, but pretty typical in others.

 

taking your points:

 

1. this cracking occurs (in my experience on less than 5% instruments, then only say 4 pad holes on an instrument). the big cracks along the grain usually need opening out and a filler of veneer applying. Often just running glue into small cracks will be enough to stabilize them and seal any air paths

1.1 pads usually need changing because they are knackered, and you change the full set together, make sure you have a supply of grommets

1.2 springs as needed?

1.4 repair shrinkage and glue failure around the pad board/ casing rebate (say 40% of instruments) I would check this before padding.

2. agreed replace all valves

3. agreed, thumb straps are a conditionally based task

4. leakage here is quite rare,  usually a roughening up of the chamois leather knap is usually all it needs

4.1 more often, ensure all reed-pan support blocks are present and fully secure, shim the top surface of the support blocks to ensure that the chamber wall gaskets are in contact with the underside of the pad board when the instrument is closed up

5. Agreed, reed assemblies have to be secure but don't over-do it, you don't want to cause reed tongue/ frame pinching

6. You shocked me with this one????? The least risk to the reed is to drop the pitch by filing with a 400grit diamond file , usually you are only looking at half a semitone, worst case just over a semitone (the case here). If you are using solder, apply a heat sink and use a very low melting point solder, soldering reed tips is usually an act of desperation. also check the underside of the reed tongues for corrosion and any accumulation of dirt, scrape off. Check also the reed frame vent's inner flanks for any accumulation of Verdigris that may foul the reed tongue. 

 

You should also expect to have some cross bushings to replace, maybe some dampers, and then action box endplate bushes (all at once) if necessary. This may require the removal of the bushing boards.

Critically any structural long woodscrews through the thumb strap and finger slides must be present and secure. Ensure the structural pillar-spacers that the long screws pass through are in place and if needs be replace the card packers on top of the pillars.

 

I hope that this helps.

 

 

 

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Dave, I think you misread Everett’s post (which, admittedly, wasn’t clear). The points you are responding to are not Everett’s words. Everything but the first line of Everett’s post (note the smaller font) comes from the technician who examined the instrument (presumably Bob Snope at the Button Box) and listed his observations and recommendations. Bob knows what he’s doing, even if it might be different from what you would do.

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I did not read it like that, never the less I shudder at the thought of soldering tips of reeds to reduce the pitch by half a semi-tone. Button Box have a good reputation, I don't know Mr. Snope, but in 30 + years I have only seen this technique applied in the manner suggested, once. When the reeds were nickel silver and too delicate to risk thinning the read tongue bodies to flatten them.

Edited by d.elliott
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I was somewhat surprised by the cracks in the pan as well. Had it spent time in a very dry climate?  I wonder.  I can't comment on the tuning method. Perhaps it is simply because it is reversible? I do expect Mr Snope knows what he is doing.  Regardless, it will be very nice when I get it back.

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There may be a misunderstanding about the tuning method. The way I understand it, the reeds are "old pitch", about 55 cents above 440. Solder is applied to bring the tone down to the right ballpark, then removed with diamond files to bring the tone up to 440. Mr Snope has done this successfully on a number of instruments. Tell me how pitch can be lowered by simply removing material from a reed?

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Taking away material near the fixed end of a reed is of course the usual method of lowering the pitch, but it is irreversible. Where's the harm in adding a tiny dab of removable material near the tip? Something like superglue would be easier to remove than solder, and also lower density, so more amenable to fine adjustment.

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3 hours ago, Richard Mellish said:

Taking away material near the fixed end of a reed is of course the usual method of lowering the pitch, but it is irreversible. Where's the harm in adding a tiny dab of removable material near the tip? Something like superglue would be easier to remove than solder, and also lower density, so more amenable to fine adjustment.

You've mentioned this in some other posts and looking to either raise or lower my Jeff duet an approximate semi-tone  it seems like a good alternative to solder/scratch even if non traditional.  The idea deserves it's own thread but a quick question;  does adding material at the base of the reed raise the pitch?

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2 hours ago, wunks said:

You've mentioned this in some other posts and looking to either raise or lower my Jeff duet an approximate semi-tone  it seems like a good alternative to solder/scratch even if non traditional.  The idea deserves it's own thread but a quick question;  does adding material at the base of the reed raise the pitch?

 

No, not reliably anyway.

 

When you add material to the tip of a reed, it lowers the pitch because of the added weight. To raise the pitch by adding material to the clamp end, it would need to make the reed stiffer. That means adding a hard, springy material. Soft solder is very un-springy, and any sort of glue would be likely to flake off due to the repeated flexing. If you tried to use a hard solder (a copper or silver alloy), the high heat required to melt the solder would draw the temper of the steel, losing its springy properties.

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2 hours ago, d.elliott said:

good luck filing off soft solder with a diamond file, the solder is too soft and will quickly glaze and choke the file. use a cut file that has been chalked and be prepared to clean the file as needed, I use copper for this.

 

 

A small scrap of sandpaper, various types will work, glued to a popsicle stick (or similar) is a cheap functional solution to remove solder on reeds that saves wear or even cleaning of finer tools. No matter how you remove soft solder, clean well and avoid inhaling the lead dust.

 

Edited by Paul Groff
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12 hours ago, Paul Groff said:

A small scrap of sandpaper, various types will work, glued to a popsicle stick (or similar) is a cheap functional solution to remove solder on reeds that saves wear or even cleaning of finer tools. No matter how you remove soft solder, clean well and avoid inhaling the lead dust.

 

I've used emery boards - the type used for filing finger nails.

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