Valve boosters/helpers

[Waldo]

The name implies their intent, but why do they only appear on the larger valves. Is there some detriment to using valve boosters [the little wires holding the valves closed] on all the valves? Can boosters be used "resurrect" weak valves, bringing them back into contact with the reed plate?

Press on...
Waldo

 

[debra]

They are only placed on the valves that need them the most. They are not placed on smaller (leather) valves to save cost. I would not suggest to use them to resurrect weak valves. When valves are "dying" they should be replaced, not resurrected. My AKKO has boosters on all the valves. I have not seen any Italian accordion with boosters on all valves, not even the most expensive ones (with leather valves).
You want boosters that are only just powerful enough to close the valve, not so strong they offer air resistance while playing (which would then lower the note's frequency). Boosters come in all sizes and thicknesses so there are really small ones you could use on small valves.

 

[Geronimo]

Valves should be weak! They need to open (and close) under as little pressure as possible. Boosters are used on those valves which are prone to open under their own weight.

When valves curl, you can often revive them by removing them, bending them back and forth until they are supple again, countercurl them until they are reasonably straight and reglue them (it's an art form which length you glue and where exactly to glue them). Keep in mind that the valve must cover the reed slot with enough excess that its edge does not interact with the reed slot edge (which makes for stuck valves and/or strange sounds), and that leather shrinks over time (I had to reglue most of my bass valves due to the shrinkage).

 

[Waldo]

Thanks for the advise. Guess I'll become a "tech".

 

[jozz]

for extra fun, you can use colored confetti to glue them on your leathers :ch