[rogerb40uk]

I am in correspondence with Jody Espina after finding a small area of pitting on the table of my JJDV, where the reed is clamped.

Jody suggests it is possibly caused by acid in saliva after leaving a wet reed on the mpc, and I have to admit to having done that occasionally...... I thought only aqua regia dissolved gold

So, a salutory lesson for all owners of GP mouthpieces.... don't leave a 'saliva-wet' reed on them for an extended period!

 

[milandro]

is it so?

I very much doubt that saliva could corrode gold plate.....that is one of the reason to have gold teeth, they are resistent to corrosion!

The saliva PH varies from very mild acid to very mild alkaline. These days there is plenty of nutters out there checking their saliva PH at least twice a day because they think that alterations of the PH indicate an early stage of illness (if your PH would change that much more you would notice changemements in you before the test tells you....)

In healthy individuals, saliva PH stays within range between 6,5 and 7,5. Hardly an aggressive chemical especially for something, like a mouthpiece, designed to be put in the mouth, in contact with saliva, for hours. True it is not a good idea to leave a wet reed on a mouthpiece, but probably for bacterial reasons more than chemical.

More significant than saliva PH values might be to be drinking soda's while playing. Now that has a significant PH shift to acid.....about 2 in some cases. Leave that for a long time on a mouthpiece and it probably makes more sense to see some effects. Probably a combination of bacteria feeding on sugars and soda's is the worst that could affect a mouthpiece.

Anyway, Mr. Espina makes mouthpieces, gold plated or not, and he should know this things and produce them in a way that they do not tarnish.

Frankly, I wouldn't take his explaination as an excuse for this to happen.

 

[rogerb40uk]

"I very much doubt that saliva could corrode gold plate.....that is one of the reason to have gold teeth, they are resistent to corrosion!"

That's a very good point, milandro...I have had some gold in my mouth, for several years too

 

[milandro]

The fact of the matter probably is that there is gold plating and gold plating.

Not all of them are created equal!

It is far too easy ( in my not so humble opinion! ) to dismiss a complaint such as yours blaming the occasional leaving of a wet reed on the mouthpiece and suggesting that your saliva is acid enough to get through the gold plating.

Impurities in (low level technology) thin plating (which I suspect is the level of a mouthpiece plating) can and will occour.

The same way cheaper stainless steel is not entirely stainless if you attack it with any corrodant or moisture, while surgical stainless steel is.... .

 

[Pete Thomas]

The same thing happened on my Lawton baritone mouthpiece IIRC.

 

[milandro]

oh yes, I believe it is a frequent problem and hardly limited to Jody mouthpieces at all, but I also believe that either there should be a disclaimer from the manufacturer (I don't know if this is the case...to be honest ) stating that occasional corrosion might occourr (instead of the otherways bombastic boasting of how fantastic is their mouthpieces being perfectly plated with the best process available on the market and 24Kt gold thin or thick plate and made from a perfect single rod of brass....) or they should take full responsability for a process that has clearly technical limitations in itself and it is obviously hardly perfect and replace or replate the occasional faulty mouthpiece instead of blaming the user with more or less phony motivations.

I believe that a company that takes responsability for their products faults and it is not dismissive of any products issue is by far to be prefered to any other. Charge me a little more for your products but don't blame me (within reason ) if things go wrong with them.

 

[rogerb40uk]

To be fair to Jody, this was simply his first thought on the subject and he's asked for more input from me, including details of where and when I bought it..... so let's cut him some slack.
He's got a reputation for being a very good guy to deal with.

I just posted as a bit of a heads-up to owners of GP mpcs, and to get some feedback on whether it's a common problem!

I have to say, though, the GP finish on the table was never as smooth as the rest of the piece.

 

[milandro]

maybe I was a bit harsh in my quick judgement which I passed before, not knowing these were only your preliminary talks with Jody Espina about this matter.
I am sorry, I apologize, for all I know, he might very well offer to replate your piece or change it for a new one then!

But on the general side, I am genuinely fed-up with all the companies (not refering to Jody Espina now) which tell their customer that any shortcoming of their products is of your doing!

This could be peraphs the practice of a Chinese mouthpiece made by a totally unknown maker costing only a few bobs, hardly acceptable if this would come from those who are selling expensive quality items.

 

[whaler]

It's probably what is under the gold plating that caused the problem.

 

[rogerb40uk]

Jody says that is nickel.

 

[dirty]

Well, isn't gold plating incredibly thin? It seems possible that the gold plate has been scratched away enough that your saliva can get through to something that would corrode or discolor.

Disclaimer: I know basically nothing about gold, metallurgy, chemistry or saliva.

 

[milandro]

I am not a metallurgist myself but I know a couple of things about this and the rest one can easily find out if you are willing to look a bit around.

Gold plating is usually several microns thick (in relative terms) or very much thinner depending on what the purpose of the item is . Whether thick or thin, any gold plated item which is going to be used, handled or polished a lot will lose, in time, the gold plating no matter how thick this is.

You cannot apply gold directly to brass, there will always be one or more layers of nickel, silver, copper, between brass and gold.

So, gold or silver plating a mouthpiece offers, at best, a temporary protection against tarnish or stains and I think is largely a stunt to make things look better than what they really are. Stainless steel or bronze are very much better......

Solid Gold or solid silver, perhaps?

 

[rini]

I have an older Link STM (Florida, it's real, I'm the first and only owner and still have the original box) that I played when I had lots of wild rock and studio gigs. On countryside gigs there often was drinking and nonchalant equipment care involved.
But surprisingly (or not?) this ill treated mouthpiece survived it all and believe me or not it still looks very much like new. Only on the facing you can see any signs of wear.

Also, I have some modern babbit Link pieces that have never seen a gig,have always been treated as carefully as possible but in spite of that are showing signs of ageing in their gold plating.

Maybe nowadays the gold plating is so thin that the silver plating underneath reacts to the chemicals of the environment?

 

[Exiled92]

It's true that saliva won't corrode gold, unless you're some really strange kind of beast... :shock: maybe a fire-breathing dragon. :angry4: I'd hazard a guess that maybe there was a pinhole flaw in the gold plating, and saliva or acidic soda residue got in there and reacted with whatever is under the gold, causing the gold to come loose. That's plausible if it's nickel, less so if it's a layer of silver under the gold.

 

[Enviroguy]

Gold is the less reactive of the heavy metals and should stand up the best again corrosion. But gold does not stick to nickel underplating nearly as well as silver underplating. That may be the problem.

 

[Dr G]

... and I'd guess that the plating is sufficiently thin as to be porous. Your saliva is attacking the layer underneath the plating.

I'd have to look up the potentials of saliva and gold to see if you can create a galvanic cell between wetted and unwetted regions.

Ewwww... take the reed off the mouthpiece and rinse them off after use.

 

[kavala]

It's probably what is under the gold plating that caused the problem.

I agree with this.

Probably prior to the plating process, there was some small pitting
in the brass. Impurities in there have managed to bubble their way
through the plating.

 

[Grumps]

It may have been back when the ESP first came out, but folks have had complaints in regard to the gold plating on JJ's before.

 

[Saxlicker]

I guess so many things will influence the plating condition whether, as suggested its the process under the gold or equally if you always eat salty chips before playing!

But for the record, the two hardiest examples of plating from my collection of ill treated mouthpieces are SR Tech and otto link.
Its a shame that my laser trimmed DG's get worse in the time it takes to blink because I still really get on with them :x

 

[Canadiain]

If there is pitting in a plated area then the plating must be flawed in some way. Gold wont disolve in saliva, but if its less than a perfect coating or was scratched or damaged in some way the material underneath can be exposed and might pit.

There are many different types and specs of gold, nickle and silver plate, different thicknesses, different chemistries, different grain sizes. Some are more there for cosmetics, some for mechanical adhesion, some for electrical performance, not all gold plate is equal, and if it gets abraded it wont do much good anyway.