A Decent Solution to Silver Plating Wear

[Rick Denney]

A pretty good over-the-counter degreaser is plain old lacquer thinner. Sometimes I miss not being able to get my hands on Freon TF anymore...

Yeah, there's nothing like TF for dissolving grease and blowing it away from instrumentation. I used it for cleaning camera shutters and apertures and nothing since works nearly as well.

Rick "who now uses Naptha but finds it doesn't remove grease, just redistributes it" Denney

[Rick Denney]

Brake cleaner? Really?

Yup. The Gunk brand is 90% tricloroethane. Some of the brands are now advertized as "non-chlorinated", but the cheaper brands are still the good stuff.

I once was spraying it on a wheel bearing, and a stream of it found a fillet and shot into my eye. I was darn glad I could feel my way to the hose on the back of the house--I flushed for 15 solid minutes before the burning stopped. In response to that idiocy, I now wear a face shield when using that stuff. And if I'm not in the great outdoors, I also wear a NIOSH-approved organic vapor mask, but that is only marginally effective for PERC toxins. Ventilation is key to staying safe with that stuff. I still only use it for particularly challenging degreasing jobs.

Rick "glad to know that it dissolves wax" Denney

[Chuck(G)]

Brake cleaner? Really?

Yup. The Gunk brand is 90% tricloroethane. Some of the brands are now advertized as "non-chlorinated", but the cheaper brands are still the good stuff.

Rick, I beg to differ. Here's a list of all Gunk product MSDS information. Both the M720 and the M749 (50 gal. only size) are mostly Tetrachloroehylene (C2Cl4), otherwise known as dry-cleaning fluid or Perc (for Perchlorethene, another name).

On the other hand, Trichloroethylene (C2HCl3) or TCE or Trike is being actively phased out of most consumer products because it's a potent carcinogen. Because of groundwater contamination, OSHA is very critical of its use and most manufacturers just don't want to fool with it.

[Rick Denney]

Rick, I beg to differ. Here's a list of all Gunk product MSDS information. Both the M720 and the M749 (50 gal. only size) are mostly Tetrachloroehylene (C2Cl4), otherwise known as dry-cleaning fluid or Perc (for Perchlorethene, another name).

On the other hand, Trichloroethylene (C2HCl3) or TCE or Trike is being actively phased out of most consumer products because it's a potent carcinogen. Because of groundwater contamination, OSHA is very critical of its use and most manufacturers just don't want to fool with it.

Well, I stand corrected. No chemist me--but I had been perusing the MSDS for Gunk brake cleaner recently for another reason and misremembered the chemical name. I never did well in chemistry, especially the organic kind.

In any case, brake cleaner is an effective degreaser that leaves no residue. But it will make you sick if you breathe too much of it, and it will burn like hell if you get it on porous parts of your body.

Rick "wondering how close this is to carbon tetrachloride, another nasty-but-effective degreaser" Denney

[Dan Schultz]

I know of a small shop here in Southern Indiana that still operates a vapor degreaser. The 'good' solvents are still stashed around but can cost as much as $300 a gallon.

This is why I DO NOT do any refinishing other that spritzing on a little touch-up out of a spray can.

Changing The World to raw brass.... one horn at a time!

[Chuck(G)]

Rick "wondering how close this is to carbon tetrachloride, another nasty-but-effective degreaser" Denney

From a molecular standpoint, not close at all. CCl4 is a model molecule, with four chlorine atoms forming a cute tetrahedron with a carbon atom at the center. This renders it perfectly nonpolar, which also makes it a very good solvent.

Unfortunately, it'll fry your brain, kidneys and liver if you inhale too much of it.

I still remember the freshman chem lab demostrantion where the instructor ignites a mixture of carbon tet and carbon disulfide and dips his hand into the flaming mixture and waves it around, thus illustrating that not all flames are hot.

ooooooooooh..... aaaaaah....

[Daniel C. Oberloh]

I have not worked with Tric or Perc in a long time and I have missed them on occasion but having had a bad experience long ago with a large vapor degreaser explosion followed with a nasty fire the explosion created, I manage to subdue my nostalgia for the days that degreasing was performed with ease and relative simplicity. Because of the laws, I am forced to use very old techniques that work well enough but are a real messy pain in the backside. Nuff said about that.

WARNING: more detailed technical crap that you probably will find of little or no value, unless you are a brass repair geek.

Back in the day... When I worked in a silversmith shop and a few plating facilities. We did spot plating over the large immersion tanks using modified artists brushes with copper, silver and gold anodes fastened to them. The anode had a wire soldered to it which connected to the anode bar on the sides of the tanks. We used the brushes (sometimes sponges) to do spot plating or touch-up work. I applied this same process to the spot plating I do in my shop today. I use JNT copper and silver plating solutions which are chloride based and short of stinging like the dickens when you get it in a cut, are relatively safe to work with, unlike cyanide solutions. I also use Vigor copper and nickel plating solutions, they are mild acid based and also safe to work with but really only work well for immersion plating. Nickel does not spot plate worth a damn and attempting to do so is a waste of time. Note: For all you guys who think you can replate a valve in a beaker, forget it. Attempting to plate valves with this stuff is an even bigger waste of time. I use copper and silver chloride for spot repairs on solder joints ONLY.

The following tips might be of use to some, probably old hat to others. The Repair Tech first cleans and solders the break, lightly polishes the area trying to avoid removing as little plate as possible. The area should be cleaned thoroughly, NO soils of any kind should remain, NONE!!! [Cleaning approach: Wet surface with Ferrees cold cleaner, gently scrub with soft lint free cloth, rinse in cold water, gently scrub with lint free soft cloth soaked hot water and Dawn dish washing liquid, cold water rinse, warm water rinse, cold water rinse, blow dry with filtered compressed air, repeat until water sheets off the surface.] The solder area should first be plated with copper because the silver will often not plate properly on the dissimilar metals. It will want to adhere to the silver and the brass but resist the lead/tin at the edges of the solder joint. Copper plate will readily cover lead/tin, brass and silver all at once. The silver will then easily cover the coppered areas. If the instrument is worn at the points of contact, forget spot plate, as spot plating won't last long enough to make the expense of the work worth while. You can however partially dismantle the horn, repair, sand polish and properly immersion plate the worn sub-assembly and reassemble using the touch up to conceal the solder joints. Works great with tubas and Euphoniums, saves time and shipping costs and is a way to avoid the unwanted complete overhaul project but still allowing for a really decent looking repair. Spot plating is not even close to the thickness and durability of conventional immersion plating but it works great at touch ups around those little solder areas provided one makes the effort of being neat and tidy with there soldering and polish work.
I suppose I will have to give the rub-on stuff another try someday. Its probably an okay application for big bare spots on sousaphone bells that were improperly repaired and over-buffed by some "skillet-head" . In my opinion, the repair shop that works on a lot of silver plate should really consider investing in a decent rectifier, anodes, brushes and plating solutions, if they really want to deliver good quality, lasting repair to there silver finishes. A little studying up and practice wont hurt ether. The equipment I have, has been with me for about fifteen years and still works great. As I recall, it was not as expensive as one would think. Less then $500 and worth every copper plated penny. Now that I have that out of my system, I will go back to my bench and try to be more productive.

Daniel C. Oberloh

Oberloh Woodwind and Brass Works
Saving the world, one horn at a time...

[Dan Schultz]

Wade, why not just send them pigs up to Anderson's and be done with it?