Curled reed valve related to tuning issue?

[stickista]

I recently noticed that 2 or 3 of my low bass notes have gone out of tune in one bellows direction only.
The reeds for each note are an octave apart, and I’m not sure which reed is off. I was going to take it into the shop when I realized that the leather valves on the off notes are curled. (See photo)

Is it possible that these leather valves may be the cause of the detune, and that replacing them may address the issue?

Also, not having done this before, what type of glue should I use to attach the new valves?
(Amazon has leather valves, buy none this exact size… am I safe getting the larger size and just triming them down to match the originals?)

 

[dak]

have gone out of tune in one bellows direction only.

Which bellows direction, and out of tune in which direction (up or down)?

when I realized that the leather valves on the off notes are curled. (See photo)

What does "on the off notes" mean to you? The valves which are open when the off notes are played, or the valves which are closed? By the way, the fourth valve from the right looks like it is not warped (from humidity) as much as its plastic booster appears to have gotten creased. When putting in the next reed block maybe?

 

[stickista]

Which bellows direction, and out of tune in which direction (up or down)?

What does "on the off notes" mean to you? The valves which are open when the off notes are played, or the valves which are closed? By the way, the fourth valve from the right looks like it is not warped (from humidity) as much as its plastic booster appears to have gotten creased. When putting in the next reed block maybe?

He off tuned note happens on opening the bellows.

Is glueing a thin strip of plastic to the outside of the valv another option for straightening it. On the one you point out, there actually is no leather valve, just a couple of strips of thin plastic.

 

[John Doe]

It's quite possible and since they surely need to be replaced in any case you might as well bite the bullet and do it.

Valves available in many sizes on EBay (Bossetto Accordions as an example). You should get as close as you can and then trim with a razor or sharp scissors. Try to keep the ends squared.

Available are all plastic (usually several leafs), plastic/leather, leather. any one of these can work. The all plastic are really easy to work with and last well. Several major reputable manufacturers now use them.

For glue I use Fiebing's Leathercraft Cement- a dab'll do you; smear the end of the valve using the removed valve as a guide for how much to cover, wait a minute or so, position it and push it down. After a couple of minutes press it down again and then it should be good to play after twenty minutes or so. DO not get it on the adjacent reed. Use the search function in this forum for other glue recommendations; there are many.

 

[Big Squeezy Accordions]

Yes, this will cause the reeds to sound out of tune. You do not want to use all plastic ventiles for low reeds, as you will hear the plastic slapping against the reed plate. Use leather backed with plastic or a metal booster. Most glues are fine for this. I use tacky glue from a craft store, but regular PVA like Elmers will work just fine.

 

[John Doe]

You do not want to use all plastic ventiles for low reeds, as you will hear the plastic slapping

Agree completely in the case of the "deep bass" reeds. For those the plastic over leather work great and silently but the plastic tends to lose its springbackitineity after a while; the conventional metal boosters on leather are more longlived. All plastic does have a bit of a faint slap as they close.

The reeds involved in the picture are all high enough pitched/small enough that the slapping noise as they close would be pretty much undetectible. Surely undetectible by me though others may have better hearing.

As an aside, one wonders how the interior leathers are faring...

I'd replace the obvious suspects and if that renders things copacetic; declare victory and play on.

 

[debra]

The cause of the detune is indeed most likely the curled-up valves. You should straighten them (remove, curl in other direction, then straighten and glue back with shoe-glue). But you should also investigate the cause of the valves being curled up. Are they getting caught in the bellow folds for instance?

 

[stickista]

Thanks for everyone’s input. I ordered a bunch of leather valves on from Amazon and replaced the 4 bent ones today, and the tuning issues are gone!
I should have posted the ‘after’ photo. Looks lovely.

Thanks!

 

[CharlieHunterFan]

Wow stickista. Great job!

I have observed this exact issue on a few of the bass notes a Bayan I recently purchased. I would love to read a more detailed description of your process. I am a bit scared to get some leathers and replace the originals.