Keeping polished brass from tarnishing?

[JerseyCity Frankie]

I want the bright shiny brass fittings I polished for a pond yacht model I am restoring to stay shiny for as long as possible. The brass parts fitted to the fairly dark deck stand out in beautiful contrast.  How can I keep the bright shiny brass looking as shiny as possible on a model where periodic repolishing is unlikely to happen?

Covering with varnish appears to be the logical solution but from what I hear, the varnish is likely to flake off. I have gleaned from online poking around that if you do all in your power to remove oils from the surface of the brass (not easy) the varnish will stick better. -Which is sound advice for any metal coating.

What say you, ship model builders?

I have noticed varnished brass instantly loses a lot of that initial flashing gold shine and turns slightly duller and greener, but that it stays in this state rather than gradually darkening. My guess is that the coating of varnish keeps the oxygen from contacting the metal. Is there another way to block the oxygen? I am bracing myself for the bad news I suspect is coming, that there is no fix for this problem. Having repeatedly polished the same brass fittings on full size vessels I feel if there was an easy way to avoid weekly polishing, sailors would have found it by now.

 

[AndrewNaylor]

Having spent many years polishing brass on yachts in my early days as a deck hand on classic yachts I have a little experience 

Polishing is the easy part as every day they get better until you go to sea and then back to square one" Dark Tarnished Dull"

Once clean and shiny you have to remove EVERY trace of polish and residue then and only then you can apply a clear Varnish. The varnish will not stick to the brass but form a protective barrier stopping the elements getting to the surface and oxidizing /dulling the surface 

Now a days I use a 2 part clear paint (Very expensive) but lasts at se for about 9 months A much cheaper alternative that will work on a pond yacht NO salt is a liquid Vinyl floor polish Apply after final installation so the screws attaching fittings are also included in the protective barrier  couple of coats should do 

Shine on 

Andy

[Jaager]

Back in the 1960s I had a brass trombone.  The clear protective finish was lacquer.  It was sprayed on, but there is brushing lacquer.  The vehicle is a warlock's brew of unpleasant organic solvents, but OK with adequate ventilation/air exhaust.  You may have to experiment to get a proper consistency for brushing or dipping to avoid too thick a layer.

[JerseyCity Frankie]

Poking around some more on the internet, Carnauba Wax rears its head again, there is mention of Carnauba in a thread on the suitability of using Beeswax to keep the lint down on thread for rigging.

Carnauba is the worlds hardest wax and is used for waxing automobiles. The paste wax sold to car enthusiasts has been adulterated with some other stuff to make the Carnauba soft enough to buff on. I wonder if I couldn't melt down some raw Carnauba and dip the brass parts in the molten wax?

[JerseyCity Frankie]

Googleing more I found this spec sheet on a U.S.dot Gov website:  http://www.gsa.gov/portal/content/112778

 

…"2.02 MATERIALS

    A.   Commercial wax or resin such as "Brasswax", or approved
         equal.

         -OR-

         Tung oil

         -OR-

         "Slipit" silicone coating, or approved equal:  

         1.   A lubricant containing silicone sold in hardware
              stores for easing sticky windows, drawers, etc.  

         2.   It is long-lasting, brass will darken only slightly
              over many years.

         -OR-

         Air-drying clear acrylic lacquer such as  "Incralac"
         (Stan Chemical Co), or approved equal.

    B.   Clean, potable water

    C.   Clean, soft cloths

[Landlocked123]

Hi JerseyCity,

 

I've been dealing with this issue since I can remember since my family had lots of brass antiques like lamps, candle sticks, fireplace tools and the like. Since I was a kid it was my responsibilty to keep it all bright. Having said that, please keep in mind that none of the brass was used constantly around water. First, there are MANY commercially available polishes, Noxon, Brasso, and the like. Regardless of what they say, they all leave a residue, which I believe actually accelerates tarnish. Sell more polish that way!

 

What I have learned is that unless something is going to remain completely untouched, sooner or later you're going to get some tarnish. The real issue is what does it look like and how easy is it to get bright again.

 

So here's my two cents worth.

 

1) if the brass is not going to receive much, if any contact or use, use whatever commercial polish you like, wipe thoroughly with Naptha or Lacquer thinner (preferably wearing cotton gloves) and spray with "StayBrite", a spray can lacquer developed especially for brass. The REAL downside is that after the item starts to tarnish (and it will) is that you have to remove ALL the lacquer before you can polish it again. I only use lacquer with complicated surfaces which are not going to be handled much.

 

2) For simple shapes like candle sticks etc. I prefer to use the commercial polish, rinse in warm soapy water, dry throughly and let be. It will tarnish again, but it will be very easy to re-polish. Besides, the brass gets an even "mellow" look before it gets bad enough to polish again.

 

 

3) My preferred method for almost every thing is to follow the steps in "1", but instead of using lacquer, I used beeswax and turpentine. (chop up beeswax, cover with turpentine in a small jar, and let sit for a few days. Adjust thickness by adding more wax or turpentine). It holds back tarnish as well as lacquer but is much easier to remove when it comes time to re polish.

 

Think about it......if brass didn't tarnish, why would we need gold?

 

Best,

John

Edited June 11, 2015 by Landlocked123

[JerseyCity Frankie]

I called around to Jewelry Repair and Wind instrument, Saxaphone repair specialists and they all recommended this product:  http://www.metalliferous.com/Nikolas-Clear-Lacquer-12-oz/productinfo/CHM2105/called  Nikolas Clear Lacquer. I am off to the city to get a can today.

[wefalck]

Traditionally, brass and silver are protected from oxidation by applying a coat of cellulose nitrate (collodium) dissolved in amylacetate, ethanol and ethylacetate. In Germany such lacquers are known under the name Zaponlack and can be bought as commercial formulations from D.I.Y. stores.