Tuning when swapping from leather to synthetic valves

[Dint]

I purchased an old Nobility piano accordion a few days ago that definitely needs it's reed valves changed out, some even being flipped upside down by a previous owner. I was thinking synthetic valves would work best for me but I don't know if swapping the old leather ones for synthetics would throw out the tuning. If it does, I'll probably stick to leather since tuning a reed sounds like a nightmare.
Also, the valves seem to vary in size a lot so I don't know what size to order. My highest pitch reed seems to be wider than some in the middle of the block, and my lowest pitch one is less wide than some, and wider than others in the same block. Should I just buy a large size and cut each one down individually?

 

[Deleted member 2438]

E
Even if you replace them all with leather - you'll need a tune-up. But if you change to plastic - the deviation will be even greater. Even if you change all the leather - you will always need a tune-up. But if you replace it with plastic - the deviation will be even greater. I recommend this job to a competent person. You have to remove all the voices ... to change the valves from the inside ... then you have to put wax on.

 

[debra]

The tuning of a reed depends on many things, but when the accordion, reed block, pallet and key travel all remain the same the tuning depends mostly on the resistance the valve offers. Reeds (especially larger ones) change a bit in frequency depending on volume, and valves also tend to have variation in resistance as they open more. It is this complex interaction that determines whether you will get a stable frequency or not. When you get a stable frequency you can do tuning to get the right frequency. With plastic valves there isn't a lot of control you have. You often have two or three layers of plastic and by keeping a layer longer or cutting it shorter you can change the frequency versus volume effect. With leather valves the stiffness of the leather can be varied, and you typically use metal booster springs which can offer more or less resistance depending on the width and thickness of the strip of metal, and by cutting the booster a bit shorter you also change how the frequency evolves, especially at low volume. You see... it's a very complex matter and not simply a choice between plastic or leather... A "perfect" tuning job is a lot of work and takes quite a bit of experimenting with the valves for the best reed behaviour. Needless to say, most (commercial) tuners do not put this much effort into the valve selection because it would make tuning way too expensive.

 

[Ventura]

my recollection of the Nobility sub-brand is as a student line
marketed to accordion schools

as the condition you mention suggests to me there would be a LOT
more wrong with it as well.. perhaps you should get a professional opinion
on whether it is reasonable to invest in these repairs before you
spend any more money on it

 

[Deleted member 2438]

Whether it's worth repairing or not is up to you... but it's always cheaper than buying a new one

 

[debra]

Whether it's worth repairing or not is up to you... but it's always cheaper than buying a new one

Without pictures of outside and inside at least... it's impossible for anyone but you to judge whether in economic terms it's worth repairing or not. But alas, while repairing is always cheaper than buying a new accordion it is not always cheaper than buying a similar used accordion that was well maintained (and thus needs no valve and/or wax replacement and no tuning). I have seen many proposals from people who are thinking of repair where that repair would cost more than the instrument is worth after repair...
And furthermore, when you want to get the first repair job right, it may and up costing much more than when you already did many accordion repairs and just start another one...
Still, all the best with the repair. Do study what the site accordionrevival.com advises to do. It's a highly valued (and free) resource for all aspiring repairers!