System Three Varnish

[Farrell]

"I was more wondering about the cosmetic quality."

Geeezzzz. You shoulda said that before - now look what you have stirred up!   ;-)

Terry Farrell

  
----- Original Message ----- 
From: "David Love" <davidlovepianos@earthlink.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: Friday, February 28, 2003 8:50 PM
Subject: Re: System Three Varnish


> 
> I'm not sure why the flexibility of the varnish would matter.  Either the
> board is stiff or it isn't.  In the case of an epoxied board, the epoxy
> provides the stiffness and the varnish topcoat is not required to
> contribute additional stiffness.  Nor would it make the epoxy any less
> stiff by virtue of its flexibility, if it is, in fact, flexible.  I have
> used varnishes for years on soundboards, usually over a shellac undercoat
> without detriment.  In this case, since I am stiffening the board with
> epoxy and System Three makes a varnish that supposedly does not have any
> compatibility with their epoxy.  I was more wondering about the cosmetic
> quality.  
> 
> David Love
> davidlovepianos@earthlink.net
> 
> 
> > [Original Message]
> > From: gordon stelter <lclgcnp@yahoo.com>
> > To: Pianotech <pianotech@ptg.org>
> > Date: 2/28/2003 4:00:05 PM
> > Subject: Re: System Three Varnish
> >
> >
> > --- Delwin D Fandrich <pianobuilders@olynet.com>
> > wrote:
> > > 
> > > OK. I bow to your far greater knowledge of chemistry
> > > and the history of
> > > varnish. I'm not a chemist--my response came from
> > > the answer to an inquiry I
> > > sent to one of the varnish-maker advertisers in
> > > WoodenBoat magazine some
> > > years back. But how do you reconcile all
> > > this with Jim Bryant's
> > > quote from Wilson Selby & Associates:
> > > 
> > > <<"ABOUT SPAR VARNISH........ (strictly our opinion)
> > > Spar Varnish has been used for years to provide a
> > > super-hard, weather and
> > > water resistant coating for exterior wood. However,
> > > this extreme hardness is
> > > not suitable for most exterior wood surfaces on a
> > > home.">>
> > > 
> > > Notice the reference to "super-hard." Not exactly a
> > > rubber sheet. And this
> > > tends to go along with my own experiences with
> > > modern "spar" varnish. Having
> > > once owned a large wooden boat I got lots and lots
> > > of experience with the
> > > stuff. Way more than I ever wanted. Sure seemed to
> > > dry hard. Could this be
> > > one of those descriptive names or terms that has
> > > changed with the times? Or
> > > is it now--the term--being misused by the
> > > manufacturers of the stuff?
> >
> > You just hit it on the head, Del! The description from
> > Wilson Delby and Associates, in typical contemporeary
> > laxity regarding the King's English, seems to be
> > confusing "Hardness" with "Toughness" which are not at
> > all the same things, at least in the normal jargon of
> > the finishing industry!
> >     Hardness, of course, refers to the molecular
> > compaction of an element or compound. A diamond is
> > hard, although it's just carbon like soft graphite,
> > for this particular reason. This molecular compaction
> > allows the rapid transmission of shockwaves, i.e. 
> > vibration, which is what I think we want in a sound
> > board finish. At the thicknesses applied, the hardest
> > of finishes will stll have plenty of flexiblity and
> > not impede the soundboard much.  Of course, hardness
> > also means susceptibility to fracture along fault
> > lines, but this is not important in soundboards
> > because no responsible customer will be bouncing rocks
> > off it, anyway! Toughness, on the other hand, relies
> > on electrons in wide orbits, and susceptible to
> > exchange with neigboring atoms. It is essential for
> > elasticity, and why static electricty can be generated
> > by rubbing, well, rubber. You are actually rubbing the
> > electrons off. It is also this elasticity which makes
> > it absorb energy, i.e. vibrations, which is why we
> > don't want to use it, or anything like it, on
> > soundboards. But we do want to use it in high-abrasion
> > situations, such as  cabinet finishes (to some
> > degree--elasticity of course impedes one's ability to
> > "rub-out" a finish") and woodwork on boats. 
> >     Come to think of it, by these criteria I believe
> > that the ideal soundboard finish would be CA glue,
> > which might also be able to, essentally, create a
> > "chemically-laminated" soundboard crown----- but I'd
> > sure hate to work in that factory!
> >
> >
> >     Surely you will agreee that a rubber sheet
> > > glued
> > > > to a soundboard would be detrimental to
> > > conventionally
> > > > accepted notions of "good tone"?  And that UV
> > > > resistance is hardly a factor we need concern
> > > > ourselves with, as a soundboard put in that much
> > > > direct sunlight would disintegrate far faster than
> > > its
> > > > finish  would. ( And anyone who would treat a
> > > piano
> > > > like that would probably be tone deaf, anyway! )
> > > 
> > > While I have never tried coating a soundboard with a
> > > rubber sheet, I have
> > > directly compared a number of soundboard finishes
> > >  In no
> > > case were we able to attribute any tonal change to
> > > the soundboard finish
> > > until the coating thickness became a significant
> > > percentage of the overall
> > > thickness and/or the coating mass became a
> > > significant percentage of the
> > > overall soundboard assembly mass. That occurred with
> > > four of five coats of
> > > epoxy and with the polyester (I don't remember the
> > > coating thickness).
> > > 
> > > And, unfortunately, I have encountered altogether
> > > too many piano which have
> > > had their soundboards exposed to eiter direct or
> > > indirect sunlight during
> > > some part of the day. This being the case, and
> > > knowing how epoxy does break
> > > down fairly rapidly when exposed to UV light, I
> > > still recommend covering any
> > > coating epoxies applied to soundboards per my PT
> > > Journal article with
> > > another finish material containing UV blockers.
> > > 
> > > Del
> >
> > Makes sense, Del, but I'd make this top coat as hard a
> > one ( not "tough" ) as I could find!
> >
> >     Thank you for the discourse.
> >     Respectfully,
> >     Gordon
> > > 
> > > _______________________________________________
> > > pianotech list info:
> > https://www.moypiano.com/resources/#archives
> >
> >
> > __________________________________________________
> > Do you Yahoo!?
> > Yahoo! Tax Center - forms, calculators, tips, more
> > http://taxes.yahoo.com/
> > _______________________________________________
> > pianotech list info: https://www.moypiano.com/resources/#archives
> 
> 
> 
> _______________________________________________
> pianotech list info: https://www.moypiano.com/resources/#archives