PianoLac v. other waterbornes (G. Newell)

[gutlo]

List,

Greg Newell asked in a post about 10 days ago, essentially to compare
PianoLac against other waterbornes for piano finishing.  This was in
conjunction with my post about Dyna 2 beating out other nmp based strippers
by a wide margin.

Such a comparison is by nature more complex than running a stripper
contest.  Rather than attempt to decide which coating is "best", it would
be useful to list the performance and application characteristic  needed in
a waterborne piano finish.

1.  The sealer must not raise the grain, or allow the topcoat to raise the
grain.  Grain raising persists up until the final coat when it becomes
painfully obvious as orange peel.
2.  The sealer should be 100% transparent, sand easily, dry fast, and
contribute to pore filling (thus eliminating pinholes).
3.  The topcoat must spray out with little or no orange peel, flow together
as it dries, and not require sanding between coats.  This last requirement
is very important:  sanding dust that isn't removed between coats will show
up as a white particle.
4. It must be exceptionally clear.  Some waterbornes impart a blue or gray
haze that shows up when a thick coat is applied and changes the color of
the substrate (red mahogany becomes purple).
5.  It must dry fast and cure in a reasonable time, ready to rub.
6.  Print resistance is very important.  Some waterbornes and solvent
lacquers will show a pronounced imprint of moving blanket, especially in
hot weather.  The inside of a moving truck can reach 120 F, softening the
coating.
7.  Wet sanding has to be easy and fast.