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Bradley Gray
01-14-2016, 10:24 PM
I have a East German conertina that is about 25 years old. It's not fancy, but had nice tone. The bellows are made of fabric - looks like muslin. Anyway, the bellows are no longer airtight. As best I can tell the air is leaking through the fabric generally over the whole surface. Any thoughts on how to seal it?

John K Jordan
01-15-2016, 12:20 AM
Bradley, I have not worked on a concertina. Long ago I did completely rebuild a player piano and replaced the cloth on all the bellows. (66 striker bellows, pump, reservoir, motor, governor, alignment, etc. Good fun! It was so leaky to start with you had to pump like crazy with both legs to get anything from it. When I was done I could play it by pushing on the foot pedal with my thumb! The fabric is a special air-tight bellows cloth made several ways - the thicker stuff is actually two layers of heavy cloth with a layer of rubber between. The thinner cloth has a tight weave coated with what looks like some type of plastic.

However, player piano bellows are extremely simple compared to those on concertinas I've seen. I found descriptions of how to build a new one from scratch - that would be a big project!

I see from a quick google search there are people that sell and repair bellows. Yikes, they are expensive! I assume you cannot find a replacement to fit so you want to repair. Google shows a lot of pages about but I didn't see one that matched your description of leaking through the fabric everywhere.

I suspect you already searched and looked at all these:
http://www.concertinaconnection.com/bellowsrepair.htm

There is a book recommended on this page:
http://www.concertina.info/tina.faq/conc-rep.htm

Another mention of repairing but no technique I could find:
http://www.concertina-repair.org.uk/page16.html

This guy appears to invite questions! Might be worth a try.
http://1accordion.net/bellows.htm

If in fact the hinges and structure are fine and the cloth is uniformly leaking and after exhaustive research AND with nothing to lose :-) if this was mine I might consider applying a flexible air-tight coating to the inside of the cloth. I would certainly look around and do some tests first to find the right substance. I have seen liquid rubber made to paint on electrical components as an insulator but I would be afraid to try that or anything else without testing it for flexibility and durability.

It does "sound" like an interesting project!

JKJ

Bradley Gray
01-15-2016, 10:10 AM
John, Thanks for your thoughtful reply. I bought this instrument new in the late 80's. At that time I was making a lot of dulcimers and had wholesale accounts for buying tuners, strings and cases. I think I paid about $50. for the concertina. it would probably not be worth buying new bellows as a new Hohner can be had for $175.

Your suggestion about the liquid insulator is worth investigating, I also thought about canvas tarp sealer.

roger wiegand
01-18-2016, 5:02 PM
Aren't concertina bellows leathered rather than done with rubber coated cloth? I think I'd choose a thin kangaroo leather if I were to re-do one. (I also rebuild player piano and player organ mechanisms.) If you had an old Wheatstone it would be worthwhile, but probably not for a $150 instrument, unless you'd like to practice. Thinking about it, it might not actually be so hard. Lots of stiffeners to place, but you can do them all on the flat and then roll it up into a cylinder, then glue and tack onto the ends. Columbia Organ Leathers and Leather Supply House both sell high quality, airtight material. Use only hot hide glue for gluing the leather-- it is unique in fracturing to yield a flexible airtight joint. I wouldn't mess with patching, that always turns out badly.