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Air leaking during drop test

Glug

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It's got to come out somewhere so it could be the pressure opening the treble pallets slightly.
But if you get a low drop test time then it could point to a leak in the treble end.

BTW. register selection will probably affect the drop test time, best to do it on master/master to get the 'worst' time.
 
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It's got to come out somewhere so it could be the pressure opening the treble pallets slightly.
But if you get a low drop test time then it could point to a leak in the treble end.

BTW. register selection will probably affect the drop test time, best to do it on master/master to get the 'worst' time.
Ok, how to fix this issue it and close treble pallets properly not breaking them?
Do you think that treble pallets could lost their good properties after long time?
 

Glug

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What drop test time are you getting ?
And what accordion is it ?

The first issue is working out where the problem is: it could be the pallets, or a hole in something (bellows, bellows gasket, case, soundboard, ...).
Take the grille off and try to find where the noise is coming from, there should be a breeze somewhere if you can hear it.

You can visually inspect the pallets from the grille side to check they're sitting over the holes correctly and shutting.
You can also take the treble end off and remove the reed blocks - put a light behind it and look from the reed side to see if you can see light leaking past the pallets (off centre or not closing).
You can try sliding a piece of thin card under each corner of a pallet to check it's pressing down evenly, or open and close it slowly and see if the corners touch down about the same time.

You can also check the 'pillows' on the pallet facing to check they're centred (if you can easily get access to the face).
 
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What drop test time are you getting ?
And what accordion is it ?

The first issue is working out where the problem is: it could be the pallets, or a hole in something (bellows, bellows gasket, case, soundboard, ...).
Take the grille off and try to find where the noise is coming from, there should be a breeze somewhere if you can hear it.

You can visually inspect the pallets from the grille side to check they're sitting over the holes correctly and shutting.
You can also take the treble end off and remove the reed blocks - put a light behind it and look from the reed side to see if you can see light leaking past the pallets (off centre or not closing).
You can try sliding a piece of thin card under each corner of a pallet to check it's pressing down evenly, or open and close it slowly and see if the corners touch down about the same time.

You can also check the 'pillows' on the pallet facing to check they're centred (if you can easily get access to the face).
Accordion Hohner Pirolla III
The rest information will be a bit later.
 
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What drop test time are you getting ?
And what accordion is it ?

The first issue is working out where the problem is: it could be the pallets, or a hole in something (bellows, bellows gasket, case, soundboard, ...).
Take the grille off and try to find where the noise is coming from, there should be a breeze somewhere if you can hear it.

You can visually inspect the pallets from the grille side to check they're sitting over the holes correctly and shutting.
You can also take the treble end off and remove the reed blocks - put a light behind it and look from the reed side to see if you can see light leaking past the pallets (off centre or not closing).
You can try sliding a piece of thin card under each corner of a pallet to check it's pressing down evenly, or open and close it slowly and see if the corners touch down about the same time.

You can also check the 'pillows' on the pallet facing to check they're centred (if you can easily get access to the face).
Did you mean the drop test where bellows are opened or closed fully?
I am just a beginner in accordion and I still feel myself a little bit confused about it.
 

Glug

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Probably my mistake, by 'drop test' I was thinking you meant paragraph 6 in http://accordionrevival.com/ACCORDION_REPAIR1.php#Air_Leaks

To find out if your leak is internal or external, measure the amount of time it takes the bellows to close under its own weight from the full open position with all valves closed....

What drop test are you meaning ?
 

yaroslav9728

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Probably my mistake, by 'drop test' I was thinking you meant paragraph 6 in http://accordionrevival.com/ACCORDION_REPAIR1.php#Air_Leaks

To find out if your leak is internal or external, measure the amount of time it takes the bellows to close under its own weight from the full open position with all valves closed....

What drop test are you meaning ?
I meant when I hold the accordion on the treble side and bellows are moving down. I am writing from another account
 

Glug

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ok :) that's similar ish.

As I said the air has to go in/out somewhere so a hissing sounds doesn't mean you've got a problem.
You have got a problem if it drops too fast.

The easy way to tell if there's an issue is to do the drop test in Accordion Revival - it's essentially what you're already doing but you time it.
Do it 2 or 3 times to check you get similar values (ie. you've worked out how to do it reliably) and do it on master/master.

And don't sit the accordion on a surface that presses on the air button (I've done that).
 

yaroslav9728

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ok :) that's similar ish.

As I said the air has to go in/out somewhere so a hissing sounds doesn't mean you've got a problem.
You have got a problem if it drops too fast.

The easy way to tell if there's an issue is to do the drop test in Accordion Revival - it's essentially what you're already doing but you time it.
Do it 2 or 3 times to check you get similar values (ie. you've worked out how to do it reliably) and do it on master/master.

And don't sit the accordion on a surface that presses on the air button (I've done that).
On your thread of Hohner Lucia piano accordion I have seen the image of pallet where it is not smooth. Is it the issue of leaking that I try to find?
I have noticed when I play on bassoon register I hear only pshhhh sound, is it related to this issue too?
 

Glug

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The pallet facing develops 'pillows' over time - the bits of the facing that are positioned over the air holes so don't get compressed when the pallet is closed. The flat area on the facing is the bit that's pressed against the soundboard and forms the air seal.

The 'pillows' should be fairly central on the pallet facing so there's an adequate flat area forming the air seal on all sides.

But you really need to do the Accordion Revival drop test to see how much of a problem you have.
Then you can locate the hissing sound, it may not be the pallets.
 

yaroslav9728

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The pallet facing develops 'pillows' over time - the bits of the facing that are positioned over the air holes so don't get compressed when the pallet is closed. The flat area on the facing is the bit that's pressed against the soundboard and forms the air seal.

The 'pillows' should be fairly central on the pallet facing so there's an adequate flat area forming the air seal on all sides.

But you really need to do the Accordion Revival drop test to see how much of a problem you have.
Then you can locate the hissing sound, it may not be the pallets.
Ok, may pallet facings lost their properties and cause air leaking?
P.S. On your thread I saw that you replaced pallet facings)
 

Glug

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That's quite possible, but there are several other things could be wrong.
You need to do the Accordion Revival drop test to see if there is a problem before doing anything else.
 

yaroslav9728

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That's quite possible, but there are several other things could be wrong.
You need to do the Accordion Revival drop test to see if there is a problem before doing anything else.
Ok, thank you. I will try.
This is my first accordion and I don't want to break something in him)
 

debra

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The first thing I would suggest is to remove the grille, then close all register sliders (some accordions have a "mute" register that closes all, but this one does not), and then do the "drop test" again. If you still hear air escaping then you know it's not going through the pallets as they are closed off.
My experience so far with accordions that leak (so you can hear a hiss) but do not have any note sounding in the "drop test" (even with a little added pressure) is that the most likely cause is a leak in the bellows gasket. You can probably find where the air escapes either by listening, by means of your eyeball (move your head around the accordion with the eyeball close to the bellows gasket and your eye is very sensitive to feel the air escaping) or by means of a piece of cigarette paper (easily moved by the wind).
 

yaroslav9728

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Hi members,
I would like to tell you what I found in my accordion when I was looking for air leaking on the treble side.

I removed the grill and then I tried to do the 'drop test' without grill and noticed that F4 note has treble leaking because of register bar is so close before pallet. Is it the reason that I am looking for fixing or not? What do you think?
 

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An easy way to test this is to put masking tape under the F4 pallet, so sticking to the soundboard and blocking air for that note. It might need 2 or 3 bits of tape.
Then try the drop test again and see what the difference is.
 

debra

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Hi members,
I would like to tell you what I found in my accordion when I was looking for air leaking on the treble side.

I removed the grill and then I tried to do the 'drop test' without grill and noticed that F4 note has treble leaking because of register bar is so close before pallet. Is it the reason that I am looking for fixing or not? What do you think?
I'm afraid I don't understand what you are trying to say with "because of register bar is so close before pallet"...
If the F4 note leaks air through the pallet then when you push hard that note will sound. In any case there are two remedies when a pallet is not closing properly: 1) the hairdryer method: heat up the wax that joins the lever (arm) and wooden pallet part so you can then push down lightly on the pallet (I also use a cardboard with a hole so as to not have the heat reach other pallets). A little bit of hot air is enough as you don't want to melt the wax completely. 2) use a "torciferri" to ever so slightly bend the lever (arm) so that the pallet is held closed with just a tiny bit more force.
Both methods are best done by an experienced repairer...
 

yaroslav9728

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I'm afraid I don't understand what you are trying to say with "because of register bar is so close before pallet"...
If the F4 note leaks air through the pallet then when you push hard that note will sound. In any case there are two remedies when a pallet is not closing properly: 1) the hairdryer method: heat up the wax that joins the lever (arm) and wooden pallet part so you can then push down lightly on the pallet (I also use a cardboard with a hole so as to not have the heat reach other pallets). A little bit of hot air is enough as you don't want to melt the wax completely. 2) use a "torciferri" to ever so slightly bend the lever (arm) so that the pallet is held closed with just a tiny bit more force.
Both methods are best done by an experienced repairer...
I meant that when I press F4 note during play I hear knock in register bar and I think but I am not sure that It could lift the key a little bit.

In addition: I have found that air leaking is in master register (in my accordion it is LMM).
What to do in this case?
 
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