[pianotech] finish on finish

[Paul McCloud]

Hi, Doug:
    Thanks for the info.  I'll try to find some You Tube videos and do some experimenting.  I'd love to see you do this in person, but I don't know if we are close enough.  Do take a stab at making a video.  Maybe a local kid or somebody could help get it up there.
    Paul McCloud
    San Diego



----- Original Message ----- 
From: Douglas Gregg 
To: pianotech at ptg.org
Sent: 11/07/2010 8:42:21 PM 
Subject: Re: [pianotech] finish on finish


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.cdgkonig.com/konigtechinfo.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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