[pianotech] finish on finish

[Douglas Gregg]

I have used various French polishing shellac, from dissolving flakes of
various colored and waxed or  dewaxed shellac, to Mohawk, and Konig ready
made products.  The traditional method (homemade) uses freshly made shellac
and various lubricating oils like olive, corn, linseed, or mineral oils that
I have tried. All methods work more or less OK. The traditional method is a
lot of work and not foolproof. Mohawk ready-made French polish solution is
OK but it is hard to get a streak-free final finish. The Konig product is
the best and is the one I use in demos. Both the Mohawk and Konig products
are one part and do not require adding oil to the shellac on th pad. You can
end up with a very nice deep gloss finish. More than 12 inches deep is
possible. That means that you can read the numbers on a ruler when held
vertically to the surface all the way up to 12 inches and more. I can
actually read the numbers on a calendar across the room in the reflection.

I have not made a video of the technique.  I do have a video camera but have
not posted a U-tube before. I guess I could learn. There is a pretty good
web site for luthiers about French polishing. It is VERY traditional, very
dogmatic, and can put many people off. I have used their technique and then
cut almost every corner and come up with equal results. Their web site is :
www.guitarsint.com/article.cfm/ArticleContentId/1

There are also videos on the web to get a basic idea about how it is done.
Just Google french poliishing and video.

I use a 2 inch round pad made of a ball of army surplus medical gauze that
is wrapped tightly and then a cover of old tee shirt is wrapped around the
gauze ball, pulled tight, given a twist, and held tightly by the twisted
end. The pad is first lightly saturated with Konig French polish. It should
barely be wet to the touch when you squeeze it. Tap it on the back of the
hand to feel how wet it is. It should barely feel wet. The French polish is
then applied in a circular pattern about a foot in diameter or less.
Continually shift the circles to make overlaping sweeps. The shellac dries
almost instantly and you can work an area for a minute before moving on if
needed. It is better at first to move on and then come back over the first
area in a few minutes. The shellac should leave some fine streaking behind
to let you know you are laying down finish. Add a few drops of French polish
liquid to the pad when the streaking stops.  You can finish up with a few
passes with the grain of the wood. When there is sufficient build up and you
feel that you are done, go over it again with a dryer pad and work it until
you have a high gloss. You are really just burnishing the finish then. After
you are done with the piece, it should dry for at least a day and then it
can be waxed.

 Those are the basics. It just takes some practice on old pieces of pianos
that you may have around the shop. It is very forgiving. Almost any mistake
can be corrected.

Be aware that the shellac finish is very shiny but can turn white if a wet
glass or plant is put on the finish for more than a few minutes. It is also
suceptible to alcohol, like whiskey.The good news is that it can be easily
repaired.

I buy Konig products direct on their web site. They have a site with
technical leaflets at www.cdg*konig*.com/*konig*techinfo.htm.
Konig has a great line of furniture retouching products that I use. The Hard
wax is used like stick shellac for filling defects and gouges. It is much
easier to use than stick shellac and very forgiving. I have filled hundreds
of dents in a black Baldwin grand top that had been tap danced on with
stilleto heels. No lie. I finished it with French polish after filling the
dents and it looked great. There are lots of war stories. I have been doing
finishing for 50 years.

Konig has a minimum order of $100 but if you call them to place the order
and tell them you are just trying out their products, they will likely wave
the minimum.  I have never been disappointed with their products. Mohawk
products are good too but not as reliable in my hands as Konig.

Douglas Gregg
Classic Piano Doc
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