Bellows check
#1
Hi everyone,

I would like to know how to check bellows on air leak in correct way and how many seconds are good  for this?
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#2
Hiya,
the reference for this is http://accordionrevival.com/ACCORDION_RE...#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. Rest your accordion on its feet on a sturdy table. Unsnap the bellows straps, grip one end of the treble keyboard in each hand, press a few keys on each end, and lift the treble section to expand the bellows. Don't mind the discordant sound as air rushes into the bellows through the random combination of open valves. Keep lifting until the bellows is all the way open and the bass section lifts off the table. Shake it a bit to make sure the bellows is fully extended, then release all the keys so all valves are closed (but don’t drop the accordion). Note the time on a clock with a sweep second hand and let the bellows close by itself under the full weight of the treble section. Don't let go, but don't hold any weight, either. Use your hands to keep the bellows going down straight, but not to hold it open or force it closed. If the bellows takes less than 35 seconds to close, it has some external air leaks, as nearly all accordions do. If it takes less than 20 seconds to close, then you probably have an external leak large enough to easily locate and repair. If it takes between 20 and 35 seconds to collapse, the leaks will be much harder to find

It's fairly easy to do once you've done it a couple of times.  Fixing air leaks is more tricky but can be done yourself.

I've got a Hohner Lucia that scored 25 seconds, it's now around 70 seconds.
https://www.accordionists.info/showthread.php?tid=5666
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#3
'Glug' pid='72516' datel Wrote:Hiya,
the reference for this is http://accordionrevival.com/ACCORDION_RE...#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. Rest your accordion on its feet on a sturdy table. Unsnap the bellows straps, grip one end of the treble keyboard in each hand, press a few keys on each end, and lift the treble section to expand the bellows. Don't mind the discordant sound as air rushes into the bellows through the random combination of open valves. Keep lifting until the bellows is all the way open and the bass section lifts off the table. Shake it a bit to make sure the bellows is fully extended, then release all the keys so all valves are closed (but don’t drop the accordion). Note the time on a clock with a sweep second hand and let the bellows close by itself under the full weight of the treble section. Don't let go, but don't hold any weight, either. Use your hands to keep the bellows going down straight, but not to hold it open or force it closed. If the bellows takes less than 35 seconds to close, it has some external air leaks, as nearly all accordions do. If it takes less than 20 seconds to close, then you probably have an external leak large enough to easily locate and repair. If it takes between 20 and 35 seconds to collapse, the leaks will be much harder to find

It's fairly easy to do once you've done it a couple of times.  Fixing air leaks is more tricky but can be done yourself.

I've got a Hohner Lucia that scored 25 seconds, it's now around 70 seconds.
https://www.accordionists.info/showthread.php?tid=5666
Do you have demonstrative any video/images how to do it in correct and carefully way?

I am new in accordion.
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#4
(01-06-2020, 09:42 PM)AccordionPlayer23 Wrote: Hi everyone,

I would like to know how to check bellows on air leak in correct way and how many seconds are good  for this?

To determine whether there is a leak in the bellows or the pallets you should first check whether you are losing more air on pull or on push. If you lose more air on push then air is leaking through the pallets. If pull or push does not matter for the leak then it's the bellows.

In addition to the other posts I would suggest to first of all start with either all register sliders closed (can be done manually on the treble side but not on the bass side but there you can set the "lightest" (highest) register. This minimizes the amount of air lost through the pallets. An accordion bellows seldom leaks (unless pierced with a sharp instrument) and in most cases the air leak is in the gasket that seals the connection between bellows and treble and/or bass side. On an old accordion replacing the gasket tape is always a good idea.
If you want to find a leak that's to be found in a certain spot somewhere you can either use your eye to feel the air coming out when the bellows is being pushed closed or you can try with a cigarette paper held on one end. A very slight puff of air will already move the paper.
Paul De Bra (not Debra...)
http://www.de-bra.nl
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#5
Would masking tape work around the perimeter of the bellows where they join the accordion on both bass and treble sides? If the leak goes away, then you'd know if it's the gaskets or something else? My bellows on my Excelsiola open by themselves with hand in bass strap, without notes depressed.
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#6
(29-06-2020, 02:53 AM)danp76 Wrote: Would masking tape work around the perimeter of the bellows where they join the accordion on both bass and treble sides? If the leak goes away, then you'd know if it's the gaskets or something else? My bellows on my Excelsiola open by themselves with hand in bass strap, without notes depressed.

What's most important to guestimate first is the *difference* in how fast the bellows opens versus closes with no notes played. If the bellows closes faster than it opens (with similar force applied) then you are losing air through the pallets of all notes combined. If the air loss is similar in both directions then it may be the bellows seal or the bellow itself. Once you know it's the bellow or the seal you can start looking for the leak. The masking tape trick is a neat idea. I have not tried it before. But... it cannot "mask" a leak if that is in the seal where the bass registers are, and my experience has been that it is precisely that area that is the hardest to seal well.
Paul De Bra (not Debra...)
http://www.de-bra.nl
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#7
A few years back I posted on finding bellows leaks. Just the other day I received a phone call on the same subject.
I was mentored by a now late but well known accordion repair tech Emil Baldoni. Emil called his method of detecting
bellows leaks "Nosing around the bellows" and it it's done like so --
First of all the upper skin of your hand and upper lip tend to be the most sensitive skin parts of your body you can use to detect air leaks. This "Nosing around the bellows" is done like so - First wet your upper lip (under your nose), place the accordion on a workbench or table and pull up the treble side to fill the bellows with air, and now by letting the weight of the treble side to close and "Nosing around the bellows" your upper lip will detect even the slightest leak. I've been "Nosing around the bellows" for 40 years now.
Owner & Operator "THE FISARMONICA SHOP" Chicopee, MA USA
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#8
I found the easiest way to locate a leak at the bellows seal was to paint soapy water at the bellows/body junction and look for bubbles while compressing the bellows.
I painted 6 inch patches and then wiped it dry to avoid leaving it wet for too long.

Might be because my upper lip has hair on it.

A stethoscope was also used to locate body / pallet leaks, and then soap to confirm the exact location.

Stethoscope: https://www.amazon.co.uk/gp/product/B004...UTF8&psc=1
with end replaced with 6" of metal tube (6mm diameter).
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