Repair Scholer Leaky Bellows - Airproofing Fabric

[Arno89]

I've got an old East German Scholer Concertina with leaky bellows.  It seams like the leaks are at the corner fabric parts. 
Could it be that the fabric is no longer air-proof?  And if so, is there something I can paint on it to make it air-proof?

I've had a look at "Coghlans Airstop", which is actually made for PVC products, but I doubt it will work.

I've tried opening up the ends to look inside the bellows, but after unscrewing the ends, the part containing the reeds are stapled/nailed in place.  So I can't see the inside of the bellows.

Does anyone have any advice for repair, or is it advisable to completely replace the bellows?

I'm trying to see if there is a cheap fix, rather than complete bellows replacement, which could be costly.

I live in South Africa and I know Danie Labuschagne can replace the bellows.  I'm just trying to see what other options there are

[Roger Hare]

There is a series of 4 videos on Youtube about the workings of these instruments:

 

https://www.youtube.com/watch?v=mbPw0yR19zM

https://www.youtube.com/watch?v=88yCVla_Djg

https://www.youtube.com/watch?v=Uvs4-ANFuq8

https://www.youtube.com/watch?v=anBj1hibG0o

 

Offhand, I can't remember if any of them deal with fixing wheezy bellows, but worth a look?

 

[Arno89]

Thanks, I do remember watching these a while ago.  Unfortunately nothing about leaky bellows.

[Stephen Chambers]

On 3/23/2021 at 8:02 AM, Arno89 said:

I've got an old East German Scholer Concertina with leaky bellows.  It seams like the leaks are at the corner fabric parts. 
Could it be that the fabric is no longer air-proof?  And if so, is there something I can paint on it to make it air-proof?

 

I'm confused, and maybe others are too - what "corner fabric parts" do you mean? The accordion bellows tape that runs all around the bellows? Or the white bellows gussets, that should be made of leather, but have sometimes been made out of impregnated cloth? A picture could be worth a thousand words...

 

Quote

I've tried opening up the ends to look inside the bellows, but after unscrewing the ends, the part containing the reeds are stapled/nailed in place.  So I can't see the inside of the bellows.

Does anyone have any advice for repair, or is it advisable to completely replace the bellows?

 

The soundboard/action board, with the reeds on the back of it, should be attached to the ends of the instrument, not to the bellows frame, and it should lift off easily.

 

The simplest answer, if you have easy access to one, might be to buy another Scholer of the same model and use it for spare parts.

 

[arkwright]

In the US there is a brand of paint called "flex seal".  I have never tried it but I understand it "dries" to a flexible rubber-like material.  (sort of like room temperature vulcanizing silicone rubber ),  It also comes as a spray.  If you had access to the inside of the bellows, you could dab a little inside the leaking corners and that might stop the leak and be almost invisible from the outside.  If you don't have access to the inside, you could try painting it on the corners from the outside, or spraying it on.  As I say I have not tried this but it seems like something to try if you have no better solution, and if you do try it, I'd be curious to know how it worked. It is rather expensive, though, like $90 per gallon; a spray can seems to be about $13.

[Don Taylor]

See near the bottom of this old article:

https://www.concertina.net/gs_stagirepair.html

 

 

[Arno89]

6 hours ago, Stephen Chambers said:

I'm confused, and maybe others are too - what "corner fabric parts" do you mean? The accordion bellows tape that runs all around the bellows? Or the white bellows gussets, that should be made of leather, but have sometimes been made out of impregnated cloth? A picture could be worth a thousand words...

Sorry I don't know the technical term.  These areas all around the concertina seems to be where the leaks are coming from.  I can't see any noticeable holes or gaps though, so my assumption is that this "material" is not airtight anymore.

[Arno89]

Thanks Arkwright and Don, I'll have a look at your suggestions as well.  I've managed to find another Scholer, also with leaky bellows, so it might be worth it to compare the two to see if they've got the same issue

 

As per the article that Don shared:
"Bellows leaks are generally not that big an issue. By using electrician's liquid tape, repairs can be readily effected, with a light coating on the inside of the bellows. If there is a large crack or tear, the trick is to lightly saturate a piece of handkerchief cloth with the liquid tape, then apply to the inside, after taping a piece of plastic wrap to the outside in order to keep the goo on the inside."

Edited March 25, 2021 by Arno89

[Tiposx]

I don't think it is a good idea to avoid separating the bellows frames from the action board. The Scholers I have worked on were easy to part. Some had paper tapes along the internal  joins to seal the assembly. If this tape is split already then you will have poor bellows pressure.  When reassembling you can use masking tape, thin packing tape or similar.

When looking for leaks I use a bright led (l.e.d.) torch inside the bellows in a dark room.

You may be surprised at where your leaks are. An artist's paintbrush and a few dabs of pva adhesive should sort it out.

Edited March 26, 2021 by Tiposx
Tipo typo

[Arno89]

So I opened up the second Scholer, and it with this one the action board is actually attached to the ends of the instrument, not the bellows like the first one.  The black fabric indicated above has a sort of plastic layer on the inside which seperated from it.  I'm going to try some Plasti Dip on the inside and see what it does