Automotive finishes

[Bdshull@AOL.COM]

Hi, Rob:

I used black automotive acrylic enamel on two or three pianos, including a 
Steinway Vertegrand about 10 years ago (I don't remember if I catalyzed it or 
not).  Seems good for your application.  You might prep the existing finish 
by sanding and filling as needed, and use a catalyzed polyester primer like 
Evercoat (I don't remember who makes Evercoat's poly primer  now, but it is 
available at auto paint stores.  This buffers between non-compatible finishes 
and creates better film strength, I believe, but you have to sand it, too;  
somewhat time-consuming.  A quickie method would be to use non-sanding primer 
instead.  Then shoot finish coats of acrylic enamel - only takes a half hour 
or 45 minutes!  You can color sand the next day through the grit sizes, with 
a final rubbing like a piano finish in satin.  It is still softer than 
lacquer.  If you wait a few weeks it is harder and more like lacquer, and you 
can machine polish to high gloss.  More so if catalyzed (catalyst delays 
machine sanding a little longer, but results in a harder film).  
If acrylic enamel is not in the sun (such as on your car in the driveway), it 
will not oxidize, and should not check.  It has pretty good film strength, 
and should seal the wood from moisture changes much better than lacquer.  It 
is very nasty stuff, requires good environmental management and respiratory 
protection.  I shot it without a mask once and nearly died - allergic 
reaction.  I'm not as smart any more either (was really smart before).  If 
you go high polish you will either leave the finish as you shot it (with 
whatever orange peel or even flow you achieved) or you will have to machine 
sand and polish. Imperfections show, so your work (prep) has to be very good. 
 Satin rubbing is more forgiving.  A dealer friend used to always shoot grand 
pianos with acrylic enamel, very fast.  I haven't done much finishing lately, 
but want to try this with an HVLP gun someday.

Let us know what you learn, and what you do -

Bill Shull
University of Redlands, La Sierra University, Riverside City College

In a message dated 00-03-14 00:55:18 EST, you write:

<< As I was working on this project today a thought occurred to me.
 What would it be like to apply an automotive finish to a piano?
 Polyester seems to be impractical for the small shop if you want
 a glossy finish, but a glossy automotive finish might be the
 ticket.  It would be harder than lacquer, more resistant to
 scratches, and have a poly-like appearance.  It would also be a
 more practical and workable material to spray in a small shop.
 
 Anybody ever experimented with this?  What do you think?
 
 Rob Goodale, RPT
 Las Vegas, NV >>