[CAUT] Vertigris on Action Rail

[Ed Sutton]

I think various oils or waxes can interact with the brass to make verdigris. It could be in the flanges, as well as in wax used to adhere the cloth. 
Copper is very reactive, and historically there were several artists pigments and colors called "verdigris." One version was made by soaking copper in some kind of tree resin, to produce a green resin that could be thinned with turpentine.
My metallurgy reference says that verdigris can form just by exposing pure copper to moist air. Brass is less reactive than copper.
Cheap woodwind instruments are sometimes made of maple impregnated with paraffin. I've seen wax exude form them when they were left in the sun.
I assume something similar can happen with paraffin impregnated piano parts if the piano gets warm enough.
It also may be that the chemical interaction of the copper and wax or oil produces an expanded product (such as happens with oxidizing key leads), which forces its way out of the bushing. Sure looks like it sometimes.
Ed S.
  ----- Original Message ----- 
  From: tannertuner 
  To: Ed Sutton ; caut at ptg.org 
  Sent: Friday, July 30, 2010 6:49 PM
  Subject: Re: [CAUT] Vertigris on Action Rail


        There's no cloth on this rail. The hammerflange rail has cloth and no noticeable vertigris, but those were not original shanks (they appear to be Hamburg shanks paired with the original (1928) NY wips at some "rebuild" several years back). How do we KNOW that vertigris was an interaction of wax (parafin) and brass? I've heard accusations that parafin used as lubricant in the bushings was the culprit (though, of course, Steinway can't seem to put a finger on it). But I've also got Baldwin Hamiltons from the 1960s with vertigris. Was parafin involved there as well? Or is something involving moisture and/or other airborne elements the cause? In other cases, why does it show up only in the flange bushings if it was used on the rail? These whip flange bushings were as green as pine needles. I figured the vertigris crept from the bushing to the rail over the past 80+ years.

        Jusk askin..
        Jeff

        --- On Fri, 7/30/10, Ed Sutton <ed440 at mindspring.com> wrote:


          From: Ed Sutton <ed440 at mindspring.com>
          Subject: Re: [CAUT] Vertigris on Action Rail
          To: caut at ptg.org
          Date: Friday, July 30, 2010, 3:59 PM


          Action verdigris is caused by an interaction of wax and brass (copper). 
          They used wax to adhere the strip of cloth to the rail.
          Take away the wax, and the verdigris won't come back.
          ES
            ----- Original Message ----- 
            From: tannertuner 
            To: caut at ptg.org 
            Sent: Friday, July 30, 2010 3:33 PM
            Subject: Re: [CAUT] Vertigris on Action Rail


                  Hi William, Thanks.
                  Yeah, I was thinking cleaner would gunk up the holes, but worried at the same time that if I didn't use something that would kill it all, it could feed on the new parts and grow back. You guys have helped diminish that concern. I don't know if I want to spray with lacquer. I've pulled some wips off of rails that were sprayed with some kind of gold lacquer and they were stuck good. That makes travelling a pain. Besides, the sheen of the rails isn't going to be all that important. The brackets don't look very nice and won't clean up, so...
                  Thanks,
                  Jeff

                  --- On Fri, 7/30/10, William Monroe <bill at a440piano.net> wrote:


                    From: William Monroe <bill at a440piano.net>
                    Subject: Re: [CAUT] Vertigris on Action Rail
                    To: caut at ptg.org
                    Date: Friday, July 30, 2010, 12:38 PM


                    Jeff,

                    I've used a green scotch-brite pad.  It leaves a satin rather than polished finish, but that's OK in my book.  Then Flitz if you like.  I've pretty much stopped using cleaners for these rails as I don't care for the gunk in all the screw holes.  It's not really the end of the world, just my preference.  Scotch brite is fast and thorough.  Then give it a quick coat of Brass-Lacquer to prevent tarnish.  When you are cleaning look very closely for cracks in the brass rail.  More often than not, they are there.

                    William R. Monroe


                     
                    On Fri, Jul 30, 2010 at 10:34 AM, tannertuner <tannertuner at bellsouth.net> wrote:

                      Hi all,
                      What's the best way to clean vertigris off the wippen rail of an old Steinway?
                      Thanks,
                      Jeff




                 
       
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