How do I remove tarnish on my pipes?
Knowledge is power.
The root cause of most tarnishing is chemicals in the air which will react with the metal surface and cause it to loose its reflectivity. A common cause of tarnish is sulfur dioxide. Oxygen also is a source.
There are three major approaches to removing tarnish:
You can make the surface shine again by abrasively removing the layer of tarnish. This approach removes the metal that has reacted be removed and exposes the untarnished layer below. The abrasives are usually finely divided silica, pumice or rouge in a carrier system such as a solution, gel or paste which makes them easier to handle.
By nature of the process, every “polish” is abrasive – some more than others. It has the potential to scar the surface (by removing non-reacted metal) if done aggressively. The important thing is that the amount of metal removed/dissolved depends on the basic abrasiveness of the product and the amount of force/friction applies. Some polishes come with applicators like abrasive wadding, pads or cloths. The "best" polish is the finest powder that is needed with as little friction as needed. Any more than that - and you're removing the very metal that you want to shine through.
My vote is to use a gentle product (I prefer liquids with low solids content with a soft cloth to get into the engraving rather than a wadded material) and to be as gentle as possible. If you have to rub very hard – you’re going to be losing metal. I’d really recommend trying a different product.
It may be difficult to completely clean engraved surfaces and the abrasive may be left in the engraving. Silver polishing cloths are typically based on this principle and will contain a reddish rouge compound that inevitably ends up lodged in the engraving. Washing the surface with water after polishing helps remove any remaining abrasive.
It is not uncommon to eventually wear through nickel coatings after 50 years of polishing. Again, gentler is better.
Many products contain a chemical base to help dissolve the oxidized metal salts. These products work by dissolving the salts faster than they dissolve the non-oxidized metal - but they will dissolve metal eventually. Some of the abrasive products have a modest amount a base to dissolve the tarnish they remove while the dip products may contain very large amount of a strong base.
Some “smell” like ammonia, but this may be a good thing! Ammonium hydroxide will evaporate after a short time and not cause any problems in the long term. The ones that “don’t smell” may have non-volatile bases that (eventually) can damage the metal and/or finish. Just to be safe, you should always rinse with water and wipe dry.
While it's nice to not have to rub, the dip products really aren't practical for mounts that are on the pipes.
This is a chemical process by which the oxidized metal is converted back to it's unoxidized form. While this sounds "ideal", it isn't always.
For silver, there are two primary chemistries, both based on reduction/oxidation chemistry.:
The first approach uses aluminum pans, really hot water and a sodium carbonate salt. It actually doesn’t remove the oxidized silver, but reduces it back to metal. Hence, there is no silver removed. The aluminum pan or sheet is microscopically dissolved. Unfortunately , but it really doesn’t work when the mount is still on the bagpipe.
The other approach is to use strong concentrations of thiourea (which smells like rotten eggs) in either an acid or base. This converts silver salts to metallic silver.
The "problem" here is that the oxidized silver was probably sitting above the surface. When it is reduced, it forms an atom of metal which deposits where it is. There are many reports of these approaches resulting in a less than shiny surface because the surface is no longer smooth. For a highly engraved pipe, this may not be an issue. For a smooth glossy surface, this might not be good. There are also reports that the surface can generally be restored with a mild polish - which just removes the metal anyway!
Some of the commercial products use petroleum products as a carrier. These can dissolve finishes and remove waxes. Other products use an alcohol diluted with water. Adding water effectively means that the solvent isn’t strong enough to damage “most” finishes – except for shellac. I favor the alcoholic/water systems.
Some people are (rightfully) very concerned about polymeric mounts. The abrasives can remove surface deposits, but if you don't rub them it shouldn't be an issue if you get a little on the material. However, many products combine an abrasive with a base. The bases used to dissolve tarnish CAN react with some things, but most plastic is quite resistant. From my practical experience, when products containing a modest amount of base are sued with care, damage to imitation ivory is NOT am issue. Still, I would strongly recommend that you WASH THE AREA WITH WATER AFTER POLISHING. (I have never used the "dip" products containing strong base.
Once you've got everything polished, lacquers and waxes can be useful in providing a barrier to the reactive molecules. These barriers will slow the rate of darkening, but it won't stop it from ever happening. Some polishes may contain waxes or other coatings intended slow down infusion of the tarnish forming agents. In my hands, they don't seem to be significantly reduce the rate of "re-oxidation".
There is also a suggestions that if you could provide a high surface area, high reactivity target for the sulfur dioxide inside your pipe case, then this should result in a reduction in the rate of oxidation during storage. I have no experience in this approach, but some people suggest using a stick of chalkboard chalk for this purpose.
I have two sets of pipes with silver and two sets of nickel plated brass (a.k.a. german silver) mounted pipes. Hence, tarnish is a concern.
I prefer a product which combines a suspension of very fine abrasives, with a touch of base in a carrier solution which doesn't harm varnish. The viscosity of the product should prevent it from "dripping" or "running" and would allow me to use it with some control . Such a product should work on both silver and nickel.
I looked at a few polishes and cleaners and have settled on liquid "Silvo" which is available in most supermarkets. The MSDS sheet is here. As you can see, it contains a polishing agent, a base and alcohol. The rest is water.
Silvo works very extremely well on both nickel and silver
and readily gets into the engraving/chasing. I use it with a soft cloth, and
rigorously wash off any residue. I am concerned about damage to other parts of the pipes, but I haven't noticed any problem with the wood or
imitation ivory near
where I've wiped it. I will say that I've been VERY careful, masking those
areas with teflon tape or food storage wrap before use and washing well
afterward. (Masking keeps the abrasive out of any space between the mounts
and the wood, too.) The only pitfall with this product is
an ammonia smell.
This product is very easy to use and the five to ten minutes every six months to keep everything absolutely bright seems like a reasonable effort. I'd guess that one can would last a whole band about three years. Be sure to rinse and wipe with a soft cloth to remove any trace of residue - just to be safe!
Ive even used it on badly tarnished nickel plated clarinet keys and it was slick!
If you'd like to protect your brilliantly polished silver, various waxes have been recommended to retard re-oxidation of the surface. Renaissance Wax is a widely recommended product. Lacquers can also provide significant protection, but application may be a problem (e.g., over-spray).
For dealing with surface tarnishing on nickel and/or silver, it is not necessary to use a purely abrasive abrasive and I cannot recommend doing so on a bagpipe. Still I have some experience working with abrasives. As a product for polishing corroded and pitted metals (including brass and nickel plated brass) I've have had good luck with MAAS and lots of elbow grease or a Dremel tool. ((Dremels generate a lot of friction and should only be used as a last resort.) The product Flitz is just not as good in my hands.
Other products that I haven't tried include Wenol, Autosol, and Nevr-Dull. Various automobile chrome or paint polishes have also been suggested. I'd be very careful about the wadding/applicators that come with some of these products.
There are also disposable wipes
made by Connoiseurs. I've tried them and they work well - at
least on silver. They do tend to leave a little bit of abrasive powder on
the surface, so a rinse is still necessary.
You can even make your own polish or your own silver dip! (Note that I cannot recommend the silver dip approach as immersing a bagpipe in water is not a good idea due to the risk of splitting/cracking.)
From the company that makes "Silvo", please note that the similar product "Brasso" uses petroleum solvents which will damage most bagpipe finishes.
Copyright S.K. MacLeod 1996-2016