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Hi

I've just aquired a new concertina (well, new to me, anyway) and about half of the buttons are impossibly stiff. For me to use, anyway.

Opening it up, the wire used for most of the springs seems very thick - there appear to be a couple of (what I assume are) 'older' springs left, which are much closer in guage to the springs supplied by Davis Leese. The rest are thick, although they look like springs made for the job.

Is this usual? The box has been repaired in the last 50 years (judging by the biro markings).

I know there are different opinions on what is the ideal button pressure - but this seems unplayable to me.

Anyone any comments?

Many thanks,

Lleanne

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Lleanne,

0.025 for phosphor bronze wire and 0.020 for steel seem to be the most popular guages for spring wire these days. An anglo air valve often needs a heavier guage and doubling up of springs.

 

My repair observations lead me to believe people often resort to what is at hand to effect q quick repair ("Any port in a storm!") I've encountered customized saftey pins and all sorts of wire configurations probably improvised to "just get by" for the moment and then forgotten to upgrade because they worked well enough.

 

In your case perhaps someone was able to make or obtain replacement springs but of a heavier guage wire than the originals.

 

I have often encountered instruments that had "oversprung action". I would venture that perhaps the instrument's pads had deteriorated and the instrument's former owner(s) had attempted to make it more air tight by bending the springs or going to a heavier guage. In many cases a change of pads makes it possible to back off the spring pressure and maintain air tightness.

 

There have been several discussions on cnet. of ideal spring pressure and how to measure and acheive it. Here are a couple of links:

 

http://www.concertina.net/forums/index.php...spring+pressure

 

http://www.concertina.net/forums/index.php...spring+pressure

 

In the final analysis your playing comfort and the instrument's playability are the ultimate determining factors.

 

Greg

 

Edited to add the necessary zeros so that I wouldn't lose my way returning from the moon.

Edited by Greg Jowaisas
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Lleanne,

0.25 for phosphor bronze wire and 0.20 for steel seem to be the most popular guages for spring wire these days. An anglo air valve often needs a heavier guage and doubling up of springs.

 

My repair observations lead me to believe people often resort to what is at hand to effect q quick repair ("Any port in a storm!") I've encountered customized saftey pins and all sorts of wire configurations probably improvised to "just get by" for the moment and then forgotten to upgrade because they worked well enough.

 

In your case perhaps someone was able to make or obtain replacement springs but of a heavier guage wire than the originals.

 

I have often encountered instruments that had "oversprung action". I would venture that perhaps the instrument's pads had deteriorated and the instrument's former owner(s) had attempted to make it more air tight by bending the springs or going to a heavier guage. In many cases a change of pads makes it possible to back off the spring pressure and maintain air tightness.

 

There have been several discussions on cnet. of ideal spring pressure and how to measure and acheive it. Here are a couple of links:

 

http://www.concertina.net/forums/index.php...spring+pressure

 

http://www.concertina.net/forums/index.php...spring+pressure

 

In the final analysis your playing comfort and the instrument's playability are the ultimate determining factors.

 

Greg

 

Thanks Greg,

That could be it (the stronger springing to cure a pad issue)... as an amateur tinkerer one doesn't know what's 'normal'. I think I may put the instrument in the hands of a proper repairer!

Lleanne

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I didn't know there was a choice... it's amazing that anyone could have played it at all, as it was (or still is, in the main - I've only tackled a few springs). A light action would make a huge difference. I'll carry on tinkering a bit more. It's do a couple of springs, then put it back together, to make sure the pads don't leak...

L

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Lleanne ,interesting you post this now. I've just finished re-springing an english concertina that should have been "playable" but the springs gave me great pain in the finger tips after 5 minutes of playing. New springs now and it's transformed the instrument. Regards Robin

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Spring weight is not solely a matter of wire gauge, preload is the important factor. Before replacing all of the springs why not unload one of the springs and see how it feels? By unload I mean bend the spring so the ends start closer together.

 

In addition, more coils = weaker spring. So a thicker steel wire with more coils and less preload may be indistinguishable from a thinner brass with less and more.

 

Chris

Edited by Chris Ghent
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Spring weight is not solely a matter of wire gauge, preload is the important factor. Before replacing all of the springs why not unload one of the springs and see how it feels? By unload I mean bend the spring so the ends start closer together.

 

In addition, more coils = weaker spring. So a thicker steel wire with more coils and less preload may be indistinguishable from a thinner brass with less and more.

 

Chris

 

Thanks Chris -

Trying out the instrument this morning, the replaced springs are still too strong. I'll do what you suggest & pre-load them a bit. This instrument has small buttons and they really hurt the fingers if the pressure isn't right (as the post above - it's nice to hear that i'm not just being a wimp) - my other instrument has bigger buttons & they are much more forgiving.

It's all a bit of a learning process - I'd put it in the hands of a repairer if there was one close! I'll see how I get on.

Thanks

Lleanne

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Lleane

 

see if you can find a weight that is around 55-60 grams and shaped such that you could balance it on the end of the button. A bolt is a good idea, you can load it with washers until the weight is right. Keep bending the spring closed until the weight just makes the button move. By the way, just in case we are talking at cross purposes here, rather than as you said " I'll do what you suggest & pre-load them a bit", what you need to do is reduce the preload by bending the top run so the two ends are slightly closer together. You will need to creep up on it slowly, no big bends, bend it as close to the coils as you can. Better to make 4 adjustments and slowly come right than to make big movements where you go each side of it.

 

 

Start with the longest lever, and see if your desired weight will seal the pad. If it won't then you will have to increase the spring preload until it does. Then make all of the others the same.

 

Chris

Edited by Chris Ghent
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.................another useful trick is to insert something like the end of a pen into the coil and bend against that;tapered is good. Then you sort of "smooth " it to a different position as you press on the inserted object.. It can help to ensure the bend is even and doesn't occur at one point on the wire. Orthodontists have special pliers that do this. You don't want the bend to be in one place.

see if you can find a weight that is around 55-60 grams and shaped such that you could balance it on the end of the button. A bolt is a good idea, you can load it with washers until the weight is right

Excellent idea, Chris. I 've been doing it by feel, which is very hit and miss.

Robin

Edited by Robin Harrison
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Spring function. On the very rare occasions when I treat my Anglo to some non-essential maintenance I apply the merest hint of light mineral oil to the coil of each spring and also to the little twist at the end of the spring where it rests in contact with the metal lever. I have no doubt that this makes sense and is beneficial. Stiff button action could perhaps also be due to lack of total freedom of movement at the pivotal joint of the lever, to which I also apply the very occasional hint of oil. (A 'hint of oil' is, in my case, virtually invisible to the naked eye and cannot possibly induce other problems unless applied in a casual, careless and heavy-handed fashion). There are those who, I believe, prefer graphite powder applied in a volatile vehicle which evaporates rapidly leaving the graphite powder in situ. I prefer the idea of oil as opposed to powder. I guess the vast majority use neither ?

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More questions (sorry)

That .025 - is this a thickness in mm?

I seem to need springs which are left handed, but which are wound up from left to right, as the right-to-left ones catch on the pivot post... may be easier to make them from scratch, rather than re-working bought ones.

So, where would I get the phosphor bronze wire from?

Thanks!

Lleanne

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More questions (sorry)

That .025 - is this a thickness in mm?

I seem to need springs which are left handed, but which are wound up from left to right, as the right-to-left ones catch on the pivot post... may be easier to make them from scratch, rather than re-working bought ones.

So, where would I get the phosphor bronze wire from?

Thanks!

Lleanne

 

 

0.025" = approx 0.63mm as per my vernier caliper readout and my failing eye sight .

 

Mike

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Hi Guys,

 

I use either

22 SWG = 0.711mm / 0.0280" (28 thou) or

23 SWG = 0.609mm / 0.0240" (24 thou) for a lighter spring.

Spring grade phosphor bronze wire.

 

A piano or harpsichord specialist suppliers should be able to supply you in small quantities

 

Dave

 

More questions (sorry)

That .025 - is this a thickness in mm?

I seem to need springs which are left handed, but which are wound up from left to right, as the right-to-left ones catch on the pivot post... may be easier to make them from scratch, rather than re-working bought ones.

So, where would I get the phosphor bronze wire from?

Thanks!

Lleanne

 

 

0.025" = approx 0.63mm as per my vernier caliper readout and my failing eye sight .

 

Mike

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Hi

I've just aquired a new concertina (well, new to me, anyway) and about half of the buttons are impossibly stiff. For me to use, anyway.

Opening it up, the wire used for most of the springs seems very thick - there appear to be a couple of (what I assume are) 'older' springs left, which are much closer in guage to the springs supplied by Davis Leese. The rest are thick, although they look like springs made for the job.

Is this usual? The box has been repaired in the last 50 years (judging by the biro markings).

I know there are different opinions on what is the ideal button pressure - but this seems unplayable to me.

Anyone any comments?

Many thanks,

Lleanne

 

 

It never ceases to amaze me how many springs get replaced by safety pin wire. These are usually far to heavy and don't have enough coils, but people clearly have managed for tens of years with these make-shift repairs.

 

When setting up the action and fine-tuning action weights, don't forget the spring force is a constant for a particular batch of springs, but the lever arm distance between key and pivot, also pivot to pad centre varies from arm to arm in any particular instrument. You need enough pressure to close a pad and keep it closed, but not too much to over resist the operation of the action. You cannot expect to set springs in place with thier arm hooks all located a uniform distance from the pivot post. By varying the contact point you can ofter sort a 'weak' spring, or reduce the effective key force.

 

Just something to be aware of : principle of levers and all that stuff.

 

Dave E

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