 The Clarinet BBoard
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Author: TAMMY
Date: 2001-05-25 21:01
they remove tarnish and polish and stuff...but how do they work?
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Author: Bart Hendrix
Date: 2001-05-25 21:55
Without actually looking at one, silver polishing materials generally work in one of two ways.
Tarnish is silver sulfide which forms when silver reacts with sulfur compounds coming in contact with it. Rubber bands, hard rubber mouthpieces and similar items in your case can be a source for the sulfur compounds.
1. The tarnish can be removed by a very mild abrasive that exposes metalic silver below.
2. Tarnish can be eliminated by a chemical reaction that reduces the silver sulfide to metalic silver. The polish binds the sulfur in materials that are then removed leaving clean, metalic silver behind. Tarnish prevention materials are designed to bind the sulfur before it reaches the surface of the silver.
While the latter approach leaves clean silver behind, it does not tend to restore the luster of a highly polished surface. For that reason, many available materials use a combination of the two approaches. The use of a chemical reaction reduces the amount of work and surface wear while the rubbing tends to restore the luster and patina of the polished metal.
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Author: L. Omar Henderson
Date: 2001-05-26 14:49
Excellent lesson Bart. I was looking for the perfect example to illustrate the concept that products with the names of manufacturers of excellent clarinets are often not the best products on the market for other purposes - see thread on VD Pet Peaves. IMHO this holds true for cork grease (petroleum based) and mineral oil based bore oils but in this case I'll try to give some insight about my investigation of silver polishing cloths sold by the "big 4". All do not contain sufficient quantities (if any at all) of tanrnish converting chemicals and all contain abrasive compounds (rouge). Many of the fine silver companies that make polishing cloths also contain small amounts of these abrasive compounds but the quality - and therefore to some extent the cost of these cloths - is in the particle size and the consistency of the particles of abrasive compound used. The smaller the particle size and the more consistent the small particle size the more expensive are these abrasive compounds. All abrasive compounds will wear away a tiny amount of the silver but the smaller the size and more consistent the particle size the less silver is worn away and the brighter the polished surface. Many cheap silver polishing cloths have mixtures of particle sizes - mostly small but with some medium and a few larger sized particles in the mix. They will polish silver but upon magnification one can see scratches caused by the larger sized abrasive particles - and the more of the plating worn away. I compared cloths in the "Line" of the big 4 using a new piece of sterling silver (which was chosen to be scratch free and also photographed) and also used a cloth made by Hagarty (a famous silver products company). I divided an area of the silver into a 5 x 5 cm grid and rubbed the silver with each cloth in one row and one column with equal pressure (this is the short-coming in this experiment because I did not quantitate this parameter). I then inspected the rows and columns with a high power dissection microscope and took a digital magnified picture of the grid. I then enlarged it and counted the numbers of visable scratches in each grid block. I've already bored you to tears with the set up of the experiment so I won't go into two pages of the data. The bottom line was that cloths of the "Big 4" all show marked scratching of the surface, some with scratches visable with just close inspection. The grids polished by the silver cloth maker were scratch free and uniformly polished. Using the grid system I could quantitate which of the cloths had the greatest apparent scratching potential which was borne out by a statistical analysis of the numbers. One can fault this experiment but the results were so obvious that they convince me. The quality of the products, at least in this instance for silver polishing cloths, sold in some of the "line" products is inferior to products available by other companies specializing in a specific area, often at a reduced price. I am not endorsing - nor bashing - any one company just giving you the information to make good choices for the products that you use on your instruments.
The Doctor
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Author: L. Omar Henderson
Date: 2001-05-26 17:57
Interesting - just got an EMail from one of the "big 4" indicating (I guess that my name is on someone's list) that they had changed suppliers of silver cloths and that the new ones were "better" - in a little back and forth bout I asked if they were going to pull the ones already on the shelf. The answer - NO! ...... So at least some one is "watching" the BB some of the time!!! I offered to do another comparison with their "new" cloth head to head again -- answer -- "well, we feel that we have an adequate product for removing tarnish from musical instrument silver keys -- 'no thank you to the comparison' " Jim - There are several great manufacturers of quality silver cloths, I mentioned one, but check out those intended for polishing high quality sterling silverware in the silver department of most large department stores.
The Doctor
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Author: Don Berger
Date: 2001-05-26 19:21
A great experience, Omar, congrats, perhaps we have a clarinet-playing silver-specialist ! Bart's comments started some chomical recollections of mine. On my wife's Ag and Cu Twinkle polishes and Hagerty's glove-spray-renewal tube all I found was an OLD patent # 24x,xxx , would guess it to be 1850-75, unavailable here. My Chem-Phy HBs gave no help, beyond how to silver mirrors!. I remembered Fehling's solution [a reducing agent??] and wondered if it [or a modern day chemical] could reduce the AgS and redeposit the Ag as would be desireable! This old Chem Eng [a plumber who has heard of chemistry] solicits yours and Bart's thots on this interesting subject. Don
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Author: Gordon (NZ)
Date: 2001-05-27 13:42
Fascinating worm food, Omar, but thanks for sharing it. (Omar & I have discussed the notion that knowledge is a parasite!) .... And more food for my cynicism towards the marketing machine and quality control in general.
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Author: Don Berger
Date: 2001-05-27 13:44
For my interests mentioned above, I made a simple patent "Boolean" search on Delphion using "silver AND polish", it turned up quite a few quite recent pats, some of which compositions contained silver compounds and reactive chemicals [for depositing purposes] as well as abrasives. Whether any of these are available commercially should be investigated, IMHO, since polishing-renewing of silver keys is at least a cosmetic problem in a comprehensive clarinet overhaul. Don
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Author: Mark Charette
Date: 2001-05-27 15:39
Just a little note - yes, there are "watchers" of this board - I get an occasional note from a few. I <b>do</b> encourage all the manufacturers / suppliers to comment when their products are discussed here.
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