In Search of the Best Finish for a Classical Guitar

Revisiting and Revising Thoughts on Guitar Finishes from a 2017 Blog Post

You can bring the surface to a smooth sheen by rubbing the wood, with the grain, using a handful of dry spokeshave shavings - before you scoff at the idea, try it.

Drew Langsner, The Chairmaker’s Workshop, 1997

The other day I consigned a cedar/Indian rosewood guitar at a guitar shop of a fairly well known guitar maker. He liked my guitars and said that I was doing "a really good job in making them", but he criticized my use of French polish.

He said "Shellac scratches too easily and it doesn't hold up well." He took one of his custom guitars off a wall hanger and showed it to me.

"Here, the way you should go is UV cured catalyzed polyester! You can finish a guitar in a day!" he boasted, "however, you have to wear a hazmat suit to enter the spray booth"

"Why would I do that?" I asked, "I have a very tiny shop and I am trying to be safe and green!"

"UV cured catalyzed polyester is THE finish we like to see these days! Looks like glass, it is hard, long wearing and very scratch resistant", he replied.

I couldn't help but to notice the slight "orange peel" on the back of the his guitar.

"I've been thinking about going to a water based finished", I said.

"Water based finishes are too pasty looking for my taste!", he fired back, "don't waste your time with them, use a catalyzed polymer or nitro lacquer!"

That was pretty much the end of the conversation and I walked out of the shop.

On the drive home I thought long and hard about what I should use to finish the two guitars that are on my work bench, they need to be finished by the first of June. French polish/shellac is the time honored way to finish high end classical guitars, but shellac takes a long time to harden and continues to shrink, ad infinitum, into any unfilled pore. Not too mention, if you look at a French polished surface cross-eyed you will more than likely scratch it. I would like to revive what George Frank called "an open pore French polish" that he said was very popular in France and the rest of the world in the 1920's. No pore filling, just shellac showing all the beauty of the wood. Problem is most classical guitar players want to own an instrument that has that "perfect factory glass-like finish". And no, no one in the flamenco or classical guitar world wants a guitar that has a soap finish [a very popular finish among amateur stick chair/furniture makers in 2017].

I have pretty much decided to go with a water-based lacquer to finish the back, sides and neck of my guitars and French polish the top. There is one company that I will be calling next week to ask "Why should I use your finish for my classical guitars" and see what they say. Their website is very informative and I like the idea of being able to rub out a finish just three to four days after applying it. If I like using a water based finish, once I complete the new workshop I will dedicate a space for a spray booth, yes, I will purchase a HVLP spray gun.

I wonder how many people who read my blog will groan at this post? Wilson not using French polish? It is a wonderful skill to have, but, I am trying to make a living at building and selling my guitars. I am not an amateur. I want the best finish possible for my guitars, that helps bring more customers to me.

Yes, I know there are many guitar makers and players who swear up and down that French polish with shellac is the best finish for a classical guitar, however...

Here is something to think about: the world famous guitar maker, Robert Ruck, who was awarded a life time achievement award from the Guitar Foundation of America in 2016, is considered the man who set the industry standard for classical guitars. He uses a catalyzed polymer finish for his guitars. Shouldn't that be the standard for all classical guitars?

I originally published the above article on my blog in 2017. And to let you know, I didn’t buy a HVLP spray gun, build a spray build and start using water based finishes. I have stayed with traditional English/French polish using shellac, grain alcohol and olive oil, using a traditional pad of old wool wrapped in a piece of cotton sheet to apply the shellac. I have learned that using any kind of finish takes time, contrary to what many “woodworkers” post on YouTube these days, a great finish cannot be completed in one day! I am now a great believer in level sanding the first several layers of shellac, making the surface as flat as possible before I start the bodying phase. A flat surface lends itself to creating a truly spectacular finish on a guitar.

A mirror reflection from the shellac.

Shellac isn’t toxic, any scratch or blemish to the finish is easily fixed, on it can be very forgiving in how it is applied and it “pops” the wood grain like no other finish! It does take a bit of a learning curve to obtain proficiency, you have to find the best combination of shellac to alcohol, the best amount of pressure to apply to the pad and when to learn to walk away from the session and let the shellac harden. The only way to become a good French polisher is practice, I have been applying shellac to my guitars for the last fifteen years and there is more for me to learn.

Tools and ingredients for French polishing: pads, pumice, shellac, grain alcohol, olive oil.

Three months after I posted the above article, I attended a guitar festival where I met a well known guitar maker who was charging $12,000 for his guitars, which were all “double tops” and finished with a UV cured catalyzed polyester. He chided me for using shellac and gave me exactly the same reasons as the owner of the music store that took my guitar on commission. He played one of my guitars and said it was “okay” and though his table was next to mine, he didn’t speak to me for the rest of the festival. Two years later, I learned that he abandoned the polyester finish and was French polishing all of his guitars. A fellow luthier told me about it and added, “Geez, Wilson, you should read what he says about French polish on his website, ‘shellac is the only finish that should be used on fine classical guitars!’ or something like that! I have to laugh that he once pushed the use of catalyzed finishes!”

A very important aspect of French polishing is pore filling, the surface of the wood needs to be flat! Every guitarist wants a guitar that looks like it was finished in a factory. Since 2017, I tried at least six different kinds of manufactured pore fillers, none of which worked as well as their advertising claimed they would. Every time I have tried one of those pore fillers, the pore filler would pull out with light sanding, so I had to refill the pores, sand, refill, sand, etc., etc. There are no chemicals or smelly fumes with pumice and shellac. I continue to use both 2F and 4F pumice with a small amount of shellac to pore fill, in the traditional manner used in the technique of French polishing.

Is my search for the best finish for a guitar over? Perhaps. Maybe. Shellac and French polishing works well for me and I know that I will continue to make guitars in a very small workshop. My current shop is 9’6” by 13’, my next shop will be between 140 to 220 square feet, a shop that tiny doesn’t lend itself well to a spray booth and exhaust fan.

Is there a best finish for guitar? A finish made out of organic materials would be best, something like a fast drying oil varnish concocted by a violin maker. A guitar will always be subjected to dents and dings, it is up to the owner to protect it from damage.