I would like to build one a verdigris zapper instead of having to borrow it from local techs. I don't know what the name of the electronic gizmos making up this thing. If anybody knows the recipe for this device or can identify the parts please let me know.

That looks like a good way to electrocute yourself!

I find soaking the joint in orange oil thinner works well, and it is much safer.

Basically it is a shorted transformer, the whole contraption is just wrong from an electrical point of view and somewhat dangerous (there is a small chance that a shorted transformer will catch fire). It could be replaced by something like low voltage high current constant power power supply, unfortunatelly I don't recall anything off the shelf that can do the job and you won't be able to make it yourself without any electronic knowledge.

As of replicating exactly this thing, just don't.

Those things were made back in the day when you could get away with almost anything. It didn't work as advertised either AFAIK.

Peter Grey Piano Doctor

2 1.5 volt D cell batteries in parallel with leads going to each side of the centre pin will do the same thing, and may also start a fire, but not as big of a fire as that device.

Why not just tazer the pin and be done with it?

PFPE (Fomblin) lubricant from Supply88 would be a much safer bet.

Tried this suggestion. Didn't produce enough electricity to do anything. Don't do this or you'll also be wasting your money on D cell batteries.

It was a joke

I adapter a pistol grip soldering iron once to see how it worked - not worth the effort, but a reasonable way to make one if really interested. After removing the soldering tip, I took two pieces of #4 solid copper wire, flattened one end and stuck the other end in the gun.

The PTG recently published an article comparing some different methods of dealing with verdigris. One was using Fantastik spray cleaner.
I've tried it myself, and so far it's actually working on an old S&S hammer flange.

Love to have a chemist explain what the three chemicals categorized as "hazardous" in Fantastik actually are and do. Take a look at the MSDS. Also the ph is 12 meaning very alkaline. I wonder how that enters into its effectiveness.

Peter Grey Piano Doctor

Do you have a link to the MSDS? I can gladly have a look. (I ask because I see various spray cleaners on their website, and I'm not sure which one was used for the verdigris treatment.)

https://www.google.com/url?sa=t&source=web&rct=j&url=https://victoryfoodservice.com/wp-content/uploads/SDS-700190-FOR-ALL-PURPOSE-FANTASTIK-CLEANER.pdf&ved=2ahUKEwjz9quhut33AhUuk4kEHTJWB0wQFnoECAUQAQ&usg=AOvVaw3nMwgkCl-lzGhklIfYVsx6

Peter Grey Piano Doctor

Peter,

Sorry for the long read, but here's what I could find - and my best shot at an explanation of its apparent efficacy.

All three ingredients are surfactants. The rest of the formulation would be mostly water, a bit of fragrance and colourant, possibly a small amount of volatile solvents, and probably some pH regulator.

The second and third listed ingredients are classical quaternary ammonium surfactants (also classified as ionic, specifically cationic). They are ubiquitous in various combinations and variations in a multitude of cleaners, detergents, etc., and are not necessarily / readily biodegradable (and hence, are also becoming ubiquitous in the environment). Often they also have antimicrobial activity, hence their use in household cleaners. They can irritate mucous membranes and are often toxic to aquatic organisms, which would explain their listing under hazardous ingredients.

The first listed ingredient is an alkyl polyglycoside surfactant, made from plant-based sugars / polysaccharides / starches and fatty alcohols. They are biodegradable and to my knowledge, less irritating than the ionic ones. You can also see that the lethal dose is much higher, i.e. it is much less toxic. Actually, I'm a bit surprised to see it listed as hazardous.

A surfactant's primary function is to make hydrophilic (water loving) and hydrophobic (water repelling) substances miscible.

And yes, you are quite correct in noting that pH 12 represents quite a strongly alkaline medium.

So, in summary, we have a cocktail of three surfactants dissolved in mostly water, at a high pH. Now, concerning the effect on a Steinway flange with verdigris, my educated guess would be:

1) The surfactants would wash out any oily, greasy residue, perhaps from previous, old-school efforts at lubrication. They would also wash out the wax "lube and seal" treatment that S&S apparently applied to their flanges by dipping them in molten wax (someone recently posted this here, as a part explanation for the verdigris problem).
2) The water content in the cleaner would temporarily swell the pinning, sizing the bushing, similar to the alcohol-and-water method.
3) Although this is conjecture, I think the alkalinity may help to dissolve some of the verdigris (which is a mixture of copper salts, e.g. copper acetate). It would certainly help neutralise any acids that caused the verdigiris in the first place.

What remains to be seen, is whether the cocktail treatment would leave the flange in a stable state, or whether corrosion would re-emerge over the long term.

If it were my project, I'd certainly rinse the flanges in water, rather than leave the cleaner (being so alkaline) on them to dry. The cleaner has already wetted them, so an additional rinse won't do any (more) harm.

Very interesting, thanks very much! You could send this to the PTG journal as an addendum to this month's article.

Mark,

Yes, thank you very much for this analysis. Always handy to have a chemist around to decipher all these mysterious ingredients.

My personal method for years now (which I learned from Bob Bartnik) has been to spray it with automotive starting fluid (he specified that it must contain ether [di-ethyl ether or some thing similar]). Then blow it out while wet with compressed air. Several applications does a "pretty good" job at dissolving and eradicating the verdigris. However it always comes back. My latest experiment has been to disassemble it, clean everything out, then re-pin with a rolled and plated pre-cut SS pin (as used in Teflon bushings). The idea here is to eliminate the exposure to copper from a cut pin that might restart the reaction. We shall see how long that lasts. In theory one could do the same with Fantastik.

Peter Grey Piano Doctor

(Di-ethyl) ether is a potent degreasing solvent, but highly volatile. It evaporates almost instantly, so I wouldn't expect it to achieve much against the actual mineral (copper salt) content of the verdigris, but it would probably dissolve and wash away any residual fat / grease / oil / sludge that may be acting as a "glue" keeping the verdigiris together.

Peter, your most recent method sounds very sensible. The SS content of the pin should be pretty inert to corrosion. But you also say it's plated. It would be good to know with what. Perhaps Nickel? If the plating is indeed Nickel, then using an alkaline cleaner such as Fantastik may be a good option for cleaning out the bushings, as Nickel is generally resistant to corrosion in caustic media (more than in acidic media). The Fantastik would neutralise the acids in the bushing before you re-pin it. That would augur well for long-term stability of the repair.

I'd love to get my hands on a typical set of verdi-grisly flanges. I've never seen it in person, nor tried to remedy it.

Mark,

SS in this context refers to Steinway & Sons whereas I believe you were interpreting it as Stainless Steel (not the case). The pins SS developed for use with the (now defunct) Teflon bushings are standard center pins (AFAIK), pre-cut to length, then tumbled to eliminate any and all sharp edges, then plated (though I cannot attest to the plating material content). There is no exposed brass/copper alloy. And...they currently cost $99/oz. plus shipping in the US. They are a good center pin, though limited in sizes.

Peter Grey Piano Doctor

Ah, my bad! I was in chemist's mode, in another part of my muddled brain, indeed thinking that you meant stainless steel. I should have known - after all, I've seen "SS" on the forums hundreds of times, referring to Steinway & Sons. (The price of those pins, though! Ouch.)

Banter aside, even though the inside of the pins is normal centre pin material (presumably some brass / copper alloy, as you wrote), I wouldn't be surprised if the plating is Nickel.

I've tried lighter fluid followed by CPL seemed to help. Not sure if it eliminates it.