My first bellow built

[Shuenhoy]

Just for fun, I built a bellow for one of the cheap Chinese factory made 40b Concertinas I own in this summer vacation.

 

 

I generally followed the Tedrow method, though I were unable to exactly reproduce it due to lack of experiences, skills and tools.

I found this method is very clever and designed for someone who is professional and wants to build the bellows efficiently, but not suitable for someone like me that does not have a table bandsaw. I used a hand saw and the result is that the sizes of each card are not accurate. I would just cut individual cards if I were to build another bellow, which would be slower and more laborious but I think it will be more robust.

 

The other problem I had was with the glue, I used PVA glue and I found it very difficult to glue the leather to the leather. After the initial gluing, I spent a lot of time gluing the leaky parts again. Perhaps a Titebond adhesive would be better. I know hide glue is a common choice, but it's a bit tricky for a non-professional like me.  It could also be because I was using a 0.2mm thick synthetic leather though, I'm not sure.

 

While my building is far from perfect, it is indeed much better than the original bellow, thanks to the building method.

 

I have learned a lot and understand the structure of the bellows.  Now I have many ideas on how to build a bellow more easily for the non-professionals, such as making some auxiliary parts with 3D printing.  I might try these ideas after I finish my PhD in 2026 or 2027. I probably should also buy a concernina built by the top makers to better understand the feelings of the best bellows before the next building.

[Alex West]

Good effort!  There's no need to buy a whole new concertina though.  If you go to Alex Holden's website (https://www.holdenconcertinas.com/) and search through his concertina build stories, you'll see how he makes his bellows.  Every maker has their own methods (adapted to their tools, experience and ability) and every one can have an opinion as to what is and what makes the best bellows, but following Alex's stories and looking at the improvements he's made along the way will give you a good start.

 

Alex West

[Lappy]

Nice job! What is the thickness of the cards you used please?

[genepinefield]

What was your experience with a low-cost 40-button Anglo concertina with the original bellows and is the internal structure like?
I'd appreciate it if you could write a review on a different topic.

[Shuenhoy]

8 hours ago, Lappy said:

Nice job! What is the thickness of the cards you used please?

 

I used a pressboard for electrical purposes of 0.8mm thinkness. I looks similar to the "Presspan" board that has been mentioned past in this forum.

 

2 hours ago, genepinefield said:

What was your experience with a low-cost 40-button Anglo concertina with the original bellows and is the internal structure like?
I'd appreciate it if you could write a review on a different topic.

 

Oneday I may start a new topic about it, but now let me make a brief review here for you.

 

As I see you are located in Japan, I believe this is the same nameless 40b model you can buy from celtnofue (with maybe different quality control and potential post-processing tweaks like re-waxing). 

 

I can see the actions are similar to the the higher 30b models of the factory (i.e. celtnofue Heather and Shamrock models) instead of the Stagi style button. But the bass reed frame is similar to a Stagi.

The hand straps are also in the Stagi style.

You can find further details about its internal structure from a video of someone repairing one of the button from the Chinese video website Bilibili: https://www.bilibili.com/video/BV1k34y1L7d9 . 

 

Different from their higher 30b modes that have been marketed under various brands (Blazefine, celnofue, ICC, etc., but not including McNeela, whose models look similar but are indeed different), their 40b model is rare. I only see Blazefine (in China) and celnofue (in Japan) selling them. Its exclusivity suggests a potentially marginal status, which could limit the flow of feedback needed to refine and improve the manufacturing process over time.

 

As for my experiences, the major issue is the stiffness of the bellow. And as the fold depth is shallow, there is often no enough air.  If I give higher 30b models bellow a score of 60/100, then I can only give this bellow a score of 35/100.  Maybe it is worse than the lower 30b model (i.e. celnofue Furze), where the bellow has 8 folds at least.  (just my guess, I have never tried a lower 30b model)

 

While the treble reeds are ok, the responsibilities of the bass reeds are slow. I have to push for a while to hear its sound.  The factory states the reeds are also from Czech (harmonikas.cz?), but I do find their sound is different from the higher 30b model. Probably this model uses Czech reeds of a lower class.

 

On the plus side, it's currently the most accessible 40b model in the world, with ample stock and a low price. It's also easy to upgrade by replacing the bellows and reeds. The bellows can be only upgraded to the level of the higher 30b model, which will not be costy (I heared a craftman in Tianjin, China, can make a 8 fold leather bellow with about 300 CNY, still Accordion style continuous card bellow, of course), instead of the laborious individual card bellow like what I did.  A set of Tipo a Mano reeds for a 30b from Harmonikas costs about 50 EUR. While the price for a 40b set would be a bit higher, it's still quite affordable.  If someone want to buy the 40b model, I think they must be prepared to make some upgrade by themselves.

Edited September 8 by Shuenhoy

[Shuenhoy]

9 hours ago, Alex West said:

Good effort!  There's no need to buy a whole new concertina though.  If you go to Alex Holden's website (https://www.holdenconcertinas.com/) and search through his concertina build stories, you'll see how he makes his bellows.  Every maker has their own methods (adapted to their tools, experience and ability) and every one can have an opinion as to what is and what makes the best bellows, but following Alex's stories and looking at the improvements he's made along the way will give you a good start.

 

Alex West

Thanks Alex for mentioning the Holden Concertina website. It is a joy to read these wonderful posts. I will definitely learn a lot from them!

 

My main purpose is still to learn the instrucment better, and my current concertinas do not satisfied me. So a new concertina is on my plan. I would probably order an ICC Eiru Silver or an Edgely New Model, or other models in the similar price range. I think I might learn something about the bellow construction from the new concertina, but that would be just a side benifit.

 

Haoran Sun

[Julian Macdonald]

I'd be interested to know what you thought of the gussets of the original bellows.

I have a 30 button anglo no-name concertina (but identical to the ones you see under Scarlatti or Trinity College) with gussets of a sort of rubberised cloth that lose air because the rubber layer has cracked from flexing. Bought second hand so I don't know how much use it's had, but otherwise in mint condition so I guess the gussets were never much good. Cheers Julian 

[David Lay]

Shuenhoy,

Please share where you found you can order a single set of Harmonikas reeds. 

I tried the Chinese factory link but could not read it without English. 

Also, you mentioned having used synthetic leather, which I expect is vinyl.  As such, PVA was probably not the best glue and will likely continue to be a problem.  PVA works best on materials that are porous (paper, wood) and absorb the PVA a bit.  I am not sure what I would use to bond a vinyl "leather" - perhaps contact cement?

[SIMON GABRIELOW]

What about vulcanising fluid ( like in the bicycle kits)? It has to grip innertube  material, which is used under pressure, and for parts always moving and yet has to remain flexible once dried.

Only a guess ( from a hardy cyclist!)🌝

[Shuenhoy]

3 hours ago, Julian Macdonald said:

I'd be interested to know what you thought of the gussets of the original bellows.

I have a 30 button anglo no-name concertina (but identical to the ones you see under Scarlatti or Trinity College) with gussets of a sort of rubberised cloth that lose air because the rubber layer has cracked from flexing. Bought second hand so I don't know how much use it's had, but otherwise in mint condition so I guess the gussets were never much good. Cheers Julian 

Julian, Upon receiving the originals bellows, the gussets did appear to have some cracks. However, my tests showed that there were no air leaks yet. I'm not sure what problems this might cause with continued use.

 

 

2 hours ago, David Lay said:

Shuenhoy,

Please share where you found you can order a single set of Harmonikas reeds. 

I tried the Chinese factory link but could not read it without English. 

Also, you mentioned having used synthetic leather, which I expect is vinyl.  As such, PVA was probably not the best glue and will likely continue to be a problem.  PVA works best on materials that are porous (paper, wood) and absorb the PVA a bit.  I am not sure what I would use to bond a vinyl "leather" - perhaps contact cement?

David, I found the price in this thread (I did not try to order one by myself, though): 

I am not sure what the factory link you found, the factory building this 40b is named Tianjin Zhongling Musical Instruments Manufacturing Factory (In Chinese: 天津市中玲乐器制造厂). I do not find they have an official website. I found them because they attended the Music China Expo 2024, you can search and find some information in the expo website:  https://online.musicchina-expo.com/24MusicListEn/#/home?ExhID=8595

 

The synthetic leather is of Polyurethane (PU) material, is that the same as vinyl?  Before building, I saw some discussion about that PVA is not very suitable for such scenario. But I never knew what exactly the issue is at that time, and I did not want to make my first building process too complicated, so I use PVA for everything for simplification. I will definitely use other types of glue if I were to build another bellow.

Edited September 8 by Shuenhoy

[David Lay]

59 minutes ago, Shuenhoy said:

Julian, Upon receiving the originals bellows, the gussets did appear to have some cracks. However, my tests showed that there were no air leaks yet. I'm not sure what problems this might cause with continued use.

 

 

David, I found the price in this thread (I did not try to order one by myself, though): 

I am not sure what the factory link you found, the factory building this 40b is named Tianjin Zhongling Musical Instruments Manufacturing Factory (In Chinese: 天津市中玲乐器制造厂). I do not find they have an official website. I found them because they attended the Music China Expo 2024, you can search and find some information in the expo website:  https://online.musicchina-expo.com/24MusicListEn/#/home?ExhID=8595

 

The synthetic leather is of Polyurethane (PU) material, is that the same as vinyl?  Before building, I saw some discussion about that PVA is not very suitable for such scenario. But I never knew what exactly the issue is at that time, and I did not want to make my first building process too complicated, so I use PVA for everything for simplification. I will definitely use other types of glue if I were to build another bellow.

Maybe easiest to switch to goat leather than to use the synthetic leather again. 🤔

[4to5to6]

 Very nice! Congratulations on your first bellows!

[genepinefield]

I'm replacing the gussets on this type of concertina with goat leather, and am currently working on my 8th or 9th. I would like to make a bellows someday, but I'm not good at cutting.

https://concertina.pinefield.asia/gusset-repairs-synthetic-leather-concertina-bellows/

[Ken_Coles]

Hats off to each of you! My brother, who eventually became an electrical engineer, said that when you want to repair something, not being afraid to take it apart is half the battle. Maybe one day some of us will follow your example.

 

Ken

[Shuenhoy]

1 hour ago, genepinefield said:

I'm replacing the gussets on this type of concertina with goat leather, and am currently working on my 8th or 9th. I would like to make a bellows someday, but I'm not good at cutting.

https://concertina.pinefield.asia/gusset-repairs-synthetic-leather-concertina-bellows/

 

Your blog post is inspiring! I did not have a jig, and that indeed cause some trouble to me. If I had read your post about your method for building a jig, the building must be better (I have to admit there is still some slight leak on my bellow.  I think one of the reasons is the absence of the jig, so that the presure is not enough on some parts).  

 

As for cutting, my idea is that the original Tedrow's method of cutting a whole sheet block requires skills and experiences.  However, directly cutting the board into all individual trapezoids should be not that hard (just consuming more time). I assume this can be relatively easily done with a guillotine paper cutter.  I am sure you will do better than me!

[genepinefield]

On 9/17/2025 at 8:17 PM, Shuenhoy said:

 

Your blog post is inspiring! I did not have a jig, and that indeed cause some trouble to me. If I had read your post about your method for building a jig, the building must be better (I have to admit there is still some slight leak on my bellow.  I think one of the reasons is the absence of the jig, so that the presure is not enough on some parts).  

 

As for cutting, my idea is that the original Tedrow's method of cutting a whole sheet block requires skills and experiences.  However, directly cutting the board into all individual trapezoids should be not that hard (just consuming more time). I assume this can be relatively easily done with a guillotine paper cutter.  I am sure you will do better than me!

When using trapezoidal paper shapes to make bellows, it is difficult to cut them.
So I wondered if I could use the same cutting dies used for processing leather, and when I asked a company that makes cutting dies, they said that they could also be used for paper. I don't use a press, they cut it out with a hammer.
https://www.internationalleatherclub.com/leather-die-cutter/

Apparently the blade of the die breaks after making one bellows. I heard it can be made for around 20 pounds.

Edited September 19 by genepinefield

[Shuenhoy]

1 hour ago, genepinefield said:

When using trapezoidal paper shapes to make bellows, it is difficult to cut them.
So I wondered if I could use the same cutting dies used for processing leather, and when I asked a company that makes cutting dies, they said that they could also be used for paper. I don't use a press, they cut it out with a hammer.
https://www.internationalleatherclub.com/leather-die-cutter/

Apparently the blade of the die breaks after making one bellows. I heard it can be made for around 20 pounds.

 

How to you think about things like these?

 

This cannot be used for Tedrow method like a table band saw, but I assume it can cut the individual trapezoids and seems relatively safe.

[alex_holden]

I use a pair of Wiss W1226 12" carpet shears to cut my bellows cards. I have in the past tried various guillotines and mat board cutters, and I struggled to make them cut exactly on the line. You can also use a trim knife on a cutting mat; I made one set of bellows that way but I found it to be more tiring than the carpet shears. If you use a trim knife, remember to change the blade when it gets dull.

 

I wouldn't use a cheap mini table saw. Those things look scary.