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Coupler modification question

CC_PDX

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I have an idea I might like to pursue on one of my boxes.

It has LMMH in the Bass, and I realistically never use some of the combinations provided by the 5 automatic switches.

1) LMH
2) MM
3) LMM*H
4) LM*H
5) LH

I'd like to have #4 turn into MH* or (even M) to give myself a quieter/less dense sound option.

Questions are
1) Is this decoupling of voices from a switch like this done / doable?
2) it a major modification requiring an expert or something I could attempt as a reasonably handy person?
3) is it (easily) reversible down the road?

Thanks!
 
Modifying the function of registers is not your average diy job.
The register mechanism contains 5 sliders like the one shown in the picture. Each slider has stubs as shown that push a lever open or closed, to control a single voice. Some 5 voice bass mechanism have fewer sliders because either one voice is always on and cannot be controlled (typically the second lowest) or because 2 voices are always on or off together.
To change the function of a register switch stubs (in the position of that switch) have to be removed or added. Removing is easy (just grind or file them off) but adding requires glueing and riveting a new stub on without adding any significant thickness to the combination, because the sliders are very close together in the register assembly.
This is also not easily reversible because the process of reversing it is a new register modification. The "undo" procedure and the "do" procedure are the same, just with different stubs.
PA171668.jpg
 
Modifying the function of registers is not your average diy job.
The register mechanism contains 5 sliders like the one shown in the picture. Each slider has stubs as shown that push a lever open or closed, to control a single voice. Some 5 voice bass mechanism have fewer sliders because either one voice is always on and cannot be...

Thanks for the detailed response, as usual, Paul. That gives me an excellent sense of what is involved.

Do all/most automatic couplers follow that same system under the hood, i.e. it is a vaguely "standardized" system across makers and decades?
 
Thanks for the detailed response, as usual, Paul. That gives me an excellent sense of what is involved.

Do all/most automatic couplers follow that same system under the hood, i.e. it is a vaguely "standardized" system across makers and decades?
The way registers has been standardized for at least the past 6 decades or so. There are few manufacturers, and they make register mechanisms according to the spec of an accordion manufacturer. You can buy register mechanics with all stubs in place, meaning that none of the register switches can do anything. Then you can turn this "dummy" mechanics into a working one by simply removing the stubs you don't want. Again this is a delicate job in the sense that when you make a mistake (remove a stub that should actually be left in) it's hard to correct.
 
As already mentioned one or more of your slides will have to be modified.
I've been modifying these treble & bass slides for some 40 years now and I don't
recommend it for a novice as any mistakes made on a slide will render it useless.
 
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Thanks for all the insight and you’ve convinced me not to try it myself.

I’m sure there are good reasons, but it makes me wonder why none of the makers of these mechanisms ever developed a threaded / removable stub for a more flexible configuration.
 
Novice question -
- would it be more appropriate to simply fashion a completely new slider?
Just looking at the photo which Paul posted, it does not seem to be impossible, nor excessively complicated.

(Please write your answers on both sides of the paper - double spaced where possible) ;)
 
Ffingers,
Someone, recently, posted a thread about having printed a coupler slide using a 3D printer 🙂
 
Thanks for all the insight and you’ve convinced me not to try it myself.

I’m sure there are good reasons, but it makes me wonder why none of the makers of these mechanisms ever developed a threaded / removable stub for a more flexible configuration.
The one thing that is feasible, and non-destructive, is to get a 0,5mm sheet of aluminium and "cut out" new sliders with stubs in the new places you want them. Easy if you have a CNC machine (which I do not have), a lot more work if you have to use manual saw, drill and files, but it can be done, and if it in the end fails, or you don't like the end result in terms of sound, you can still go back to the original sliders.
 
Ffingers,
Someone, recently, posted a thread about having printed a coupler slide using a 3D printer 🙂
I believe that was for the sliders that go under the reed blocks. It's not feasible for the register mechanism because 1) these sliders are not constrained between two flat surfaces and 2) the stubs have too be stronger than you can get from thin plastic.
I have seen accordions with plastic sliders under the reed blocks (my Hohner Artiste X S has them for instance) but never for the sliders in the switch mechanism.
 
I believe that was for the sliders that go under the reed blocks. It's not feasible for the register mechanism because 1) these sliders are not constrained between two flat surfaces and 2) the stubs have too be stronger than you can get from thin plastic.
I have seen accordions with plastic sliders under the reed blocks (my Hohner Artiste X S has them for instance) but never for the sliders in the switch mechanism.
but not all printing is done with plastics - there are metalic versions - and even concrete (but that would be a little heavy, eh?!)
I was thinking along the line of aluminium strip punched out and cut to the shape and size required.
 
but not all printing is done with plastics - there are metalic versions - and even concrete (but that would be a little heavy, eh?!)
I was thinking along the line of aluminium strip punched out and cut to the shape and size required.
Yes, a 0,5mm aluminium strip cut to shape is the way to go for the best result (more solid than the stubs you can add and rivet on). Anything you 3D print in 0,5mm thickness is going to be weaker than a solid aluminium strip.
 
Thanks for all the insight and you’ve convinced me not to try it myself.

I’m sure there are good reasons, but it makes me wonder why none of the makers of these mechanisms ever developed a threaded / removable stub for a more flexible configuration.
well, there WAS a better configuration

a guy named Pancotti

a company named Excelsior New York

simple rocker switches.. one per reed bank..
push to engage, push again to silence

absolute power for the individual musician in their choice of reed combinations

this system, however, required people to make decisions
and think
 
well, there WAS a better configuration

a guy named Pancotti

a company named Excelsior New York

simple rocker switches.. one per reed bank..
push to engage, push again to silence

absolute power for the individual musician in their choice of reed combinations

this system, however, required people to make decisions
and think
We gotta think too?
 
well, there WAS a better configuration

a guy named Pancotti

a company named Excelsior New York

simple rocker switches.. one per reed bank..
push to engage, push again to silence

absolute power for the individual musician in their choice of reed combinations

this system, however, required people to make decisions
and think
I play CBA and all my playing life I have wanted an accordion with this type of switching but as far as I'm aware none were ever made. Am I correct?
 
well, there WAS a better configuration

a guy named Pancotti

a company named Excelsior New York

simple rocker switches.. one per reed bank..
push to engage, push again to silence

absolute power for the individual musician in their choice of reed combinations

this system, however, required people to make decisions
and think
This system required people to select a register (a combination of reed banks to be on or off) like playing a chord, or like a series of individual notes, all of which take time. Registers are not something you select and then start playing a whole song. A lot of compositions and arrangements for accordion require you to change registers almost instantly. You may get a 1/8 rest if you are lucky, 1/4 feels like having ages to switch... and that's why chin switches were invented to do register changes fast without using the hand that is playing.
When I make arrangements for accordion ensembles I try to give players either a bit of time to change a register or perhaps a choice of using a "compromise register" without changing every time... but really, you have to be able to switch from any register to any other register in under one second. (One second feels like ages, it's not like a tire change in formula 1.)
I play in several ensembles/orchestras (using mostly arrangements by other people, so I'm not to blame). Often there is just no time at all to do a register switch. It's like one note and then the next note needs to be in a different register *immediately*. Luckily I have chin switches.
So... that "better configuration" was really abandoned because it took players too much time to switch, not because people needed to "make decisions and think".
 
absolute power corrupts absolutely !

Rocker Switches forever T-Shirts are now available in the CastleFi
Accordion Museum Gift shop
 
of course we all know that More lights, More switches, More couplers
is an indication of a Premium Product and can cost a LOT more money
like the 2 reed 5 shift and LMM 7 shifters that forced
them to go to 9 shifts on the LMH models just to stay competitive

i seem to recall a few models that even sported dual shift arrays in
ascending and descending order

Rockers Forever !
 
of course we all know that More lights, More switches, More couplers
is an indication of a Premium Product and can cost a LOT more money
like the 2 reed 5 shift and LMM 7 shifters that forced
them to go to 9 shifts on the LMH models just to stay competitive

i seem to recall a few models that even sported dual shift arrays in
ascending and descending order

Rockers Forever !
Not only dual shirt arrays in ascending and descending order, but also 5 voice instruments like the Hohner Imperator V with dual shift arrays with all different reed bank selections.
Direct selection of a reed bank through a single (rocker or other) switch is still useful, on 5 voice instruments where you essentially want all registers of a 4 voice accordion and then a toggle for the 5th voice. This is not all that uncommon.
I don't need that "more lights, more switches, more couplers...". Some accordions now follow a different setup: they have a number of chin switches for the most commonly needed registers, and then they have normal register switches for the other, less common registers. There is no need to repeat registers you already have under your chin. My Pigini bass accordion has 4 registers, and 4 identical chin registers. There is no need for the normal registers at all, and I believe that nowadays that same model comes with just the 4 chin switches.
 
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