Aluminum/steel quality and accordion longevity

[Ignacchitti]

Any info on the quality of the aluminum/steel used in accordion mechanics and other parts? In terms of corrosion resistance and strength.

I know of accordion models that used to include anodized materials in the bass mechanics in the past (50 years ago) and that nowadays are no longer treated. Chromed mechanics, I believe, are also not so common anymore.

Besides cost cutting, could these moves reflect a tendency of manufacturers to use better aluminum/steel to begin with? Or is it simply shoddy work?

 

[dak]

I don't think chromed mechanics were common: chrome was used for plating decorative bars on the grille. What has been phased out is, cough, cough, plating mechanic parts with cadmium.

 

[Ventura]

the test of time has definitively shown Aluminum mechanicals are
quite reliable and robust

Older tech that used Zinc or Pot Metal by necessity was phased out for good reason

and Brass is Brass.. useful in some specific ways

 

[Alan Sharkis]

I have heard, but cannot verify, that Petosa uses key rods made of a type of tempered aluminum that’s so hard that it cannot be bent by hand. Does anyone know if this is true? If so, is it exclusive to Petosa?

When I was a kid, bent-up keys were a common problem among young accordionists. It once happened to me, and I watched my teacher fix it in my house. But suppose the key rod couldn’t be bent by hand. Would the key + key rod + pallet assembly have to be replaced, necessitating pulling an axle? That’s not an operation easily done by a teacher in a student’s house. So, I suppose that there are disadvantages to key rods that cannot be bent by hand.

 

[Dingo40]

Any info on the quality of the aluminum/steel used in accordion mechanics and other parts? In terms of corrosion resistance and strength.

My personal peeve is shoddy chrome work which frequently doesn't last the distance (clips, bellows corners, mute covers and ornaments ).
Some makes are less durable than others.
Aluminium ornamentation will go dull but can be revived merely by rubbing with some screwed up paper towel.

 

[ColoRodney]

I was once given an accordion built in Italy during the war. Many of the mechanics were cheap pot metal, because of embargoes and needing the good metal for armaments.

 

[tcabot]

I doubt that corrosion resistance or strength would ever be a concern. Strength is, in fact, irrelevant, as you'll always have decent stopping points designed into the housing to prevent the mechs from bending - you are never actually loading the levers.
Modern Italian aluminium, Soviet pot metal and old German hand-made brass levers are all surprising easy to bend if you take them out of their housings. Just looking at any of them the wrong way is enough to cause misalignment.

Wear & tear happens on contact points in left hand side mechs, and axle/bushings (or lever if there's no bushings), but it will take many hours of playing to get to there, by which point it would be fair to say that you've had your money's worth.

So pick the one that sounds nice and don't worry about aluminium grade used in the levers.

 

[kimric]

There are pluses and minuses to making parts out of different metals.
Older instruments used brass for a lot of the bass machine, but that was later swapped for steel since this allowed spot welding in addition to soldering. The steel parts often were zinc plated to prevent corrosion. Over the decades if a instrument is in a humid environment the zinc can form a rough oxide layer that is rough, and the surface can drag on sliding parts.
Aluminum does not have these problems, but it is not a good dry bearing surface and tends to get rougher with wear. It also leave a oxide layer that can be abrasive. Anodising leaves a harder surface that can help with this. There are a lot more aluminum alloys available now but each one has things that it is good and bad at. Harder alloys can be brittle and may stress crack at sharp bends.
Things like Delrin and Teflon can be used for bearing surfaces with out having to use lubrication.
I have seldom seen pot metal (cast zinc) used in accordions since it is heavy, sometimes small parts like the register chambers and bass hardware in Atlantics can be made of stamp formed or cast aluminum.
Russian key mechansims look a LOT like old hohner hardware and is typically made of stamped steel. My beef with these is they were often not deburred so this can lead to wear.

 

[Ignacchitti]

There are pluses and minuses to making parts out of different metals.
Older instruments used brass for a lot of the bass machine, but that was later swapped for steel since this allowed spot welding in addition to soldering. The steel parts often were zinc plated to prevent corrosion. Over the decades if a instrument is in a humid environment the zinc can form a rough oxide layer that is rough, and the surface can drag on sliding parts.
Aluminum does not have these problems, but it is not a good dry bearing surface and tends to get rougher with wear. It also leave a oxide layer that can be abrasive. Anodising leaves a harder surface that can help with this. There are a lot more aluminum alloys available now but each one has things that it is good and bad at. Harder alloys can be brittle and may stress crack at sharp bends.
Things like Delrin and Teflon can be used for bearing surfaces with out having to use lubrication.
I have seldom seen pot metal (cast zinc) used in accordions since it is heavy, sometimes small parts like the register chambers and bass hardware in Atlantics can be made of stamp formed or cast aluminum.
Russian key mechansims look a LOT like old hohner hardware and is typically made of stamped steel. My beef with these is they were often not deburred so this can lead to wear.

Based on your description, it does not seem that anodizing has downsides - besides cost. Isn't that the case? Though the superficial anodized layer can be brittle it does not make the aluminum part itself brittle. It just may not be seen as extremely necessary (which is not a con of anodization itself).

 

[Rosie C]

Here is my 1930s accordion. The aluminium parts had no special treatment and they're still in good condition and quite shiny. The brass parts are a little dull but not corroded. The galvanising on the pistons is probably the worst condition as the zinc has powered slightly.