Shellac vs. lacquer

[Richard Brekne]

Bill Ballard wrote:

Interesting perspective Bill. I will have to chew on this
for a while. And I will be really interested in hearing what
you think of Shellack after you use it for a while. I might
add that one of the reasons I use Cellulose lacquer is that
it also behaves much in this fashion, and it is a softer
less brittle lacquer. If any lacquer has a "boing"
characteristic to it I have a feeling that this is the right
stuff. It also dries fast, and lends itself easily to
needling later on, and it doesnt discolour the felt
noticably.

Thanks for the thoughts and interesting reading Bill

RicB


> >If you want an idea of how Shellack is going to behave over
> >time inside the hammer take a thick dense strip of felt (for
> >example damper lift felt for the back end of grand keys) and
> >soak a short strip of it in Shellack and let dry. The have
> >fun playing around with it in as many creative ways as you
> >can think of and check out how it reacts.
> 
> 
> I should clarify. The elasticity I'd like to witness is that of the
> resin by itself. Heck you could make a reinforcer out of watered-down
> TiteBond. Its elasticity would be greater than keytop plastic. For me
> what distinguishes these resins (lac bug stools, nitro lacquer,
> shellac and keytop plastic) in their results is their springiness.
> (Oh, cure time is also a major consideration, but in the scheduling
> of the work, not necessarily in tone quality.)
> 
> I seriously doubt there is any chemical reaction between the felt
> fiber and and the resins which would degrade the fiber (and
> specifically, its elasticity). The behavior of the combination i
> would bet is entirely a mechanical matter.
> 
> Under a powerful microscope, coat a single fiber. The fiber's
> springiness is a known factor. The resin coating stiffens the fiber,
> making it slower to bend under a deforming force (ie. collision with
> taut music wire). But there's a big difference in how that fiber will
> return from the deformation, based on the elasticity of the resin.
> I'd like the resin with the greatest elasticity. Any coating can
> stiffen the fiber, I'm looking for one which will contribute some of
> its own elasticity to the fiber, after reducing the fiber's
> elasticity.
> 
> Yes the breakdown is a significant determinant in the long-term
> prospects for sound. Thanks to Richard for bringing this up. Imagine
> the resin coating as a sheath. Its brittleness/elasticity will
> determine how its will survive the flexing which occurs with each
> hammer strike. (Certainly that flexing is likely to exceed the
> elastic limits of the resin mainly at the strike point.) The
> segmentation I was exploring happens when the flexing overcomes the
> resin's limits. At that point, wouldn't the coating have fractured
> into segments. And now, coating the fiber not as a single sheath but
> in many short segments, wouldn't it it have lost the original
> stiffness it had as an integral whole sheath? Would its effect on the
> fiber now mainly be limited to its mass, now clinging on to the fiber
> i separate chunks?
> 
> This is what pricked up my ears when Richard talked about the warming
> of the sound as resin breaks down. I'm actually looking forward to
> this process with shellac, because I haven't noticed it with keytop
> plastic.
> 
> 
> I will probably do the report tomorrow night. Tuesday is one of three
> nights per week during the summer when I have two concert running, 45
> minutes drive apart.
> 
> Briefly, this is a D with the whole nine yards done last year (I did
> a new action with complete Stanwood), sitting in a concert shed
> (http://www.svac.org/2002_final/wed.html), with a theater stage and
> proscenium. I didn't push the reinforcing too hard last season, as
> I'm a firm believer in the "work-hardening" of the strike point. But
> the time hard come to make the piano project. So from that
> standpoint, the shellacing is part of the initial set-up. I got over
> there yesterday and found the piano much as I remembered it from the
> week before (and anticipated finding it). So 1.5 hours of loud
> voicing (with Zen Reinhardt's "racket-ball"), mezzo, then U.C., and
> finally quiet voicing. The piano is no ready for the opinions of
> others.
> 
> Bill Ballard RPT
> NH Chapter, P.T.G.
> 
> "I gotta go ta woik...."
>      ...........Ian Shoales, Duck's Breath Mystery Theater
> +++++++++++++++++++++